This page has only limited features, please log in for full access.
MSc in Chemical Engineering (cum laude) at Politecnico di Torino and Universidad Central de Venezuela (2004), PhD in Chemical Engineering (2009). She is currently Associated Professor of Industrial Chemistry at Politecnico di Torino and is responsible of the research team: CO<sub>2</sub> reduction for a low-carbon economy (CREST group) at DISAT department. She is specialized in heterogeneous catalysis, photo/electro-catalytic water splitting and CO<sub>2</sub> conversion technologies to high-added value products with a focus on the implementation of these carbon capture and utilisation technologies from the lab-scale (TRL2/3) to the Pilot scale (TRL5/6). She has worked in the scientific coordination teams of different EU projects: SunCoChem, RECODE, CELBICON, Artiphyction, ECO2CO2) and as principal investigator (OCEAN). She is co-author of more than 74 papers (>2100 citations) in international peer-reviewed journals, 14 book chapters. Her H-index is 27.
The electrochemical transformation of biomass-derived compounds (e.g., aldehyde electroreduction to alcohols) is gaining increasing interest due to the sustainability of this process that can be exploited to produce value-added products from biowastes and renewable electricity. In this framework, the electrochemical conversion of 5-hydroxymethylfurfural (HMF) to 2,5-bis(hydroxymethyl)furan (BHMF) is studied. Nanostructured Ag deposited on Cu is an active and selective electrocatalyst for the formation of BHMF in basic media. However, this catalyst deserves further research to elucidate the role of the morphology and size of the coated particles in its performance as well as the actual catalyst surface composition and its stability. Herein, Ag is coated on Cu open-cell foams by electrodeposition and galvanic displacement to generate different catalyst morphologies, deepening on the particle growth mechanism, and the samples are compared with bare Ag and Cu foams. The chemical–physical and electrochemical properties of the as-prepared and spent catalysts are correlated to the electroactivity in the HMF conversion and its selectivity toward the formation of BHMF during electroreduction. AgCu bimetallic nanoparticles or dendrites are formed on electrodeposited and displaced catalysts, respectively, whose surface is Cu-enriched along with electrochemical tests. Both types of bimetallic AgCu particles evidence a superior electroactive surface area as well as an enhanced charge and mass transfer in comparison with the bare Ag and Cu foams. These features together with a synergistic role between Ag and Cu superficial active sites could be related to the twofold enhanced selectivity of the Ag/Cu catalysts for the selective conversion of HMF to BHMF, that is, >80% selectivity and ∼ 100% conversion, and BHMF productivity values (0.206 and 0.280 mmol cm–2 h–1) ca. 1.5–3 times higher than those previously reported.
Giancosimo Sanghez de Luna; Phuoc H. Ho; Adriano Sacco; Simelys Hernández; Juan-Jesús Velasco-Vélez; Francesca Ospitali; Alessandro Paglianti; Stefania Albonetti; Giuseppe Fornasari; Patricia Benito. AgCu Bimetallic Electrocatalysts for the Reduction of Biomass-Derived Compounds. ACS Applied Materials & Interfaces 2021, 13, 23675 -23688.
AMA StyleGiancosimo Sanghez de Luna, Phuoc H. Ho, Adriano Sacco, Simelys Hernández, Juan-Jesús Velasco-Vélez, Francesca Ospitali, Alessandro Paglianti, Stefania Albonetti, Giuseppe Fornasari, Patricia Benito. AgCu Bimetallic Electrocatalysts for the Reduction of Biomass-Derived Compounds. ACS Applied Materials & Interfaces. 2021; 13 (20):23675-23688.
Chicago/Turabian StyleGiancosimo Sanghez de Luna; Phuoc H. Ho; Adriano Sacco; Simelys Hernández; Juan-Jesús Velasco-Vélez; Francesca Ospitali; Alessandro Paglianti; Stefania Albonetti; Giuseppe Fornasari; Patricia Benito. 2021. "AgCu Bimetallic Electrocatalysts for the Reduction of Biomass-Derived Compounds." ACS Applied Materials & Interfaces 13, no. 20: 23675-23688.
Electrochemical CO2 reduction is a promising carbon capture and utilisation technology. Herein, a continuous flow gas diffusion electrode (GDE)-cell configuration has been studied to convert CO2 via electrochemical reduction under atmospheric conditions. To this purpose, Cu-based electrocatalysts immobilised on a porous and conductive GDE have been tested. Many system variables have been evaluated to find the most promising conditions able to lead to increased production of CO2 reduction liquid products, specifically: applied potentials, catalyst loading, Nafion content, KHCO3 electrolyte concentration, and the presence of metal oxides, like ZnO or/and Al2O3. In particular, the CO productivity increased at the lowest Nafion content of 15%, leading to syngas with an H2/CO ratio of ~1. Meanwhile, at the highest Nafion content (45%), C2+ products formation has been increased, and the CO selectivity has been decreased by 80%. The reported results revealed that the liquid crossover through the GDE highly impacts CO2 diffusion to the catalyst active sites, thus reducing the CO2 conversion efficiency. Through mathematical modelling, it has been confirmed that the increase of the local pH, coupled to the electrode-wetting, promotes the formation of bicarbonate species that deactivate the catalysts surface, hindering the mechanisms for the C2+ liquid products generation. These results want to shine the spotlight on kinetics and transport limitations, shifting the focus from catalytic activity of materials to other involved factors.
Hilmar Guzmán; Federica Zammillo; Daniela Roldán; Camilla Galletti; Nunzio Russo; Simelys Hernández. Investigation of Gas Diffusion Electrode Systems for the Electrochemical CO2 Conversion. Catalysts 2021, 11, 482 .
AMA StyleHilmar Guzmán, Federica Zammillo, Daniela Roldán, Camilla Galletti, Nunzio Russo, Simelys Hernández. Investigation of Gas Diffusion Electrode Systems for the Electrochemical CO2 Conversion. Catalysts. 2021; 11 (4):482.
Chicago/Turabian StyleHilmar Guzmán; Federica Zammillo; Daniela Roldán; Camilla Galletti; Nunzio Russo; Simelys Hernández. 2021. "Investigation of Gas Diffusion Electrode Systems for the Electrochemical CO2 Conversion." Catalysts 11, no. 4: 482.
This work reports the study of ZnO-based anodes for the photoelectrochemical regeneration of the oxidized form of nicotinamide adenine dinucleotide (NAD+). The latter is the most important coenzyme for dehydrogenases. However, the high costs of NAD+ limit the use of such enzymes at the industrial level. The influence of the ZnO morphologies (flower-like, porous film, and nanowires), showing different surface area and crystallinity, was studied. The detection of diluted solutions (0.1 mM) of the reduced form of the coenzyme (NADH) was accomplished by the flower-like and the porous films, whereas concentrations greater than 20 mM were needed for the detection of NADH with nanowire-shaped ZnO-based electrodes. The photocatalytic activity of ZnO was reduced at increasing concentrations of NAD+ because part of the ultraviolet irradiation was absorbed by the coenzyme, reducing the photons available for the ZnO material. The higher electrochemical surface area of the flower-like film makes it suitable for the regeneration reaction. The illumination of the electrodes led to a significant increase on the NAD+ regeneration with respect to both the electrochemical oxidation in dark and the only photochemical reaction. The tests with formate dehydrogenase demonstrated that 94% of the regenerated NAD+ was enzymatically active.
Carminna Ottone; Diego Pugliese; Marco Laurenti; Simelys Hernández; Valentina Cauda; Paula Grez; Lorena Wilson. ZnO Materials as Effective Anodes for the Photoelectrochemical Regeneration of Enzymatically Active NAD+. ACS Applied Materials & Interfaces 2021, 13, 10719 -10727.
AMA StyleCarminna Ottone, Diego Pugliese, Marco Laurenti, Simelys Hernández, Valentina Cauda, Paula Grez, Lorena Wilson. ZnO Materials as Effective Anodes for the Photoelectrochemical Regeneration of Enzymatically Active NAD+. ACS Applied Materials & Interfaces. 2021; 13 (9):10719-10727.
Chicago/Turabian StyleCarminna Ottone; Diego Pugliese; Marco Laurenti; Simelys Hernández; Valentina Cauda; Paula Grez; Lorena Wilson. 2021. "ZnO Materials as Effective Anodes for the Photoelectrochemical Regeneration of Enzymatically Active NAD+." ACS Applied Materials & Interfaces 13, no. 9: 10719-10727.
Advances and strategies of electrocatalytic CO2 conversion to alcohols on Cu-based catalysts is assessed with an outlook of current challenges for a practical application of this technology.
Hilmar Guzmán; Nunzio Russo; Simelys Hernández. CO2 valorisation towards alcohols by Cu-based electrocatalysts: challenges and perspectives. Green Chemistry 2021, 23, 1896 -1920.
AMA StyleHilmar Guzmán, Nunzio Russo, Simelys Hernández. CO2 valorisation towards alcohols by Cu-based electrocatalysts: challenges and perspectives. Green Chemistry. 2021; 23 (5):1896-1920.
Chicago/Turabian StyleHilmar Guzmán; Nunzio Russo; Simelys Hernández. 2021. "CO2 valorisation towards alcohols by Cu-based electrocatalysts: challenges and perspectives." Green Chemistry 23, no. 5: 1896-1920.
Electrocatalytic (EC) and thermocatalytic (TC) conversion of CO2 to methanol are promising carbon capture and utilization technologies. Herein, these CO2-to-methanol conversion processes are analysed in terms of technical, environmental and economic feasibility. To this purpose, the catalytic performance of the same catalyst (CuO/ZnO/Al2O3) was evaluated in both EC and TC processes. Here is showed for the first time that this catalyst is (apart from TC route) also able to generate methanol through CO2 EC reduction. This work presents lab scale tests, scaled-up simulations and evaluates the environmental and economic performance of these processes. The carbon footprint of the TC and EC processes, scaled-up to the same productivity of ∼3 kg/h methanol, scored ∼8 kgCO2 eq/kgCH3OH. Strategies to reduce this impact are presented, such as improving the current density of the EC cell (i.e. 200 mA/cm2 results in a reduction of 68% to 2.72 kgCO2 eq/kgCH3OH) and the availability of 100% renewable electricity (saving up to 62% carbon footprint of both processes). Considering an effective allocation of the methanol productivity on a real market scenario, both the TC and EC processes would start to be economically competitive at methanol productivities > 19.1 kg/h and 3.3 kg/h, respectively. Moreover, if O2 valorisation, a low price of the renewable electricity and a carbon tax are considered, the economic profitability will rise; e.g. the minimum levelised cost of product (LCOP of 1.45 €/kg and 1.67 €/kg, respectively) could be reduced by 53%. Finally, our results pointed out that the CO2 electroreduction process must be optimized (e.g. improving catalysts performance and EC cell design reducing mass transfer limitations) to achieve industrially relevant rates and the maturity of the thermocatalytic technology.
Hilmar Guzmán; Fabio Salomone; Esperanza Batuecas; Tonia Tommasi; Nunzio Russo; Samir Bensaid; Simelys Hernández. How to make sustainable CO2 conversion to Methanol: Thermocatalytic versus electrocatalytic technology. Chemical Engineering Journal 2020, 417, 127973 .
AMA StyleHilmar Guzmán, Fabio Salomone, Esperanza Batuecas, Tonia Tommasi, Nunzio Russo, Samir Bensaid, Simelys Hernández. How to make sustainable CO2 conversion to Methanol: Thermocatalytic versus electrocatalytic technology. Chemical Engineering Journal. 2020; 417 ():127973.
Chicago/Turabian StyleHilmar Guzmán; Fabio Salomone; Esperanza Batuecas; Tonia Tommasi; Nunzio Russo; Samir Bensaid; Simelys Hernández. 2020. "How to make sustainable CO2 conversion to Methanol: Thermocatalytic versus electrocatalytic technology." Chemical Engineering Journal 417, no. : 127973.
The newly synthesized dinuclear uranyl salen coordination compound showed excellent photocatalytic reduction of CO2 to methanol.
Mohammad Azam; Umesh Kumar; Joshua O. Olowoyo; Saud I. Al-Resayes; Agata Trzesowska-Kruszynska; Rafal Kruszynski; Mohammadd Shahidul Islam; Mohammad Rizwan Khan; Syed Farooq Adil; Mohammad Rafique Siddiqui; Fahad Ahmed Al-Harthi; Abdul Karim Alinzi; Saikh Mohammad Wabaidur; Masoom Raza Siddiqui; Mohammed Rafi Shaik; Suman L. Jain; M. Amin Farkhondehfal; Simelys Hernàndez. Dinuclear uranium(vi) salen coordination compound: an efficient visible-light-active catalyst for selective reduction of CO2 to methanol. Dalton Transactions 2020, 49, 17243 -17251.
AMA StyleMohammad Azam, Umesh Kumar, Joshua O. Olowoyo, Saud I. Al-Resayes, Agata Trzesowska-Kruszynska, Rafal Kruszynski, Mohammadd Shahidul Islam, Mohammad Rizwan Khan, Syed Farooq Adil, Mohammad Rafique Siddiqui, Fahad Ahmed Al-Harthi, Abdul Karim Alinzi, Saikh Mohammad Wabaidur, Masoom Raza Siddiqui, Mohammed Rafi Shaik, Suman L. Jain, M. Amin Farkhondehfal, Simelys Hernàndez. Dinuclear uranium(vi) salen coordination compound: an efficient visible-light-active catalyst for selective reduction of CO2 to methanol. Dalton Transactions. 2020; 49 (47):17243-17251.
Chicago/Turabian StyleMohammad Azam; Umesh Kumar; Joshua O. Olowoyo; Saud I. Al-Resayes; Agata Trzesowska-Kruszynska; Rafal Kruszynski; Mohammadd Shahidul Islam; Mohammad Rizwan Khan; Syed Farooq Adil; Mohammad Rafique Siddiqui; Fahad Ahmed Al-Harthi; Abdul Karim Alinzi; Saikh Mohammad Wabaidur; Masoom Raza Siddiqui; Mohammed Rafi Shaik; Suman L. Jain; M. Amin Farkhondehfal; Simelys Hernàndez. 2020. "Dinuclear uranium(vi) salen coordination compound: an efficient visible-light-active catalyst for selective reduction of CO2 to methanol." Dalton Transactions 49, no. 47: 17243-17251.
High level of atmospheric carbon dioxide (CO2) concentration is considered one of the main causes of global warming. Electrochemical conversion of CO2 into valuable chemicals and fuels has promising potential to be implemented into practical and sustainable devices. In order to efficiently realize this strategy, one of the biggest efforts has been focused on the design of catalysts which are inexpensive, active and selective and can be produced through green and up-scalable routes. In this work, copper-based materials are simply synthesized via microwave-assisted process and carefully characterized by physical/chemical/electrochemical techniques. Nanoparticle with a cupric oxide (CuO) surface as well as various cuprous oxide (Cu2O) cubes with different sizes is obtained and used for the CO2 reduction reaction. It is observed that the Cu2O-derived electrodes show enhanced activity and carbon monoxide (CO) selectivity compared to the CuO-derived one. Among various Cu2O catalysts, the one with the smallest cubes leads to the best CO selectivity of the electrode, attributed to a higher electrochemically active surface area. Under applied potentials, all Cu2O cubes undergo structural and morphological modification, even though the cubic shape is retained. The nanoclusters formed during the material evolution offer abundant and active reaction sites, leading to the high performance of the Cu2O-derived electrodes. Graphic abstract
Juqin Zeng; Micaela Castellino; Katarzyna Bejtka; Adriano Sacco; Gaia Di Martino; M. Amin Farkhondehfal; Angelica Chiodoni; Simelys Hernández; Candido F. Pirri. Facile synthesis of cubic cuprous oxide for electrochemical reduction of carbon dioxide. Journal of Materials Science 2020, 56, 1255 -1271.
AMA StyleJuqin Zeng, Micaela Castellino, Katarzyna Bejtka, Adriano Sacco, Gaia Di Martino, M. Amin Farkhondehfal, Angelica Chiodoni, Simelys Hernández, Candido F. Pirri. Facile synthesis of cubic cuprous oxide for electrochemical reduction of carbon dioxide. Journal of Materials Science. 2020; 56 (2):1255-1271.
Chicago/Turabian StyleJuqin Zeng; Micaela Castellino; Katarzyna Bejtka; Adriano Sacco; Gaia Di Martino; M. Amin Farkhondehfal; Angelica Chiodoni; Simelys Hernández; Candido F. Pirri. 2020. "Facile synthesis of cubic cuprous oxide for electrochemical reduction of carbon dioxide." Journal of Materials Science 56, no. 2: 1255-1271.
Bismuth vanadate (BiVO4) have surface states that give rise to defect levels that mediate electron-hole recombination. In order to minimize the inefficiencies, an ultrathin Al overlayer was deposited on the BiVO4 electrodes. A 54% improvement on the photocurrent density was obtained using the Al- modified BiVO4 electrode, accompanied by a 15% increase in stability over 7.5 hours of continuous irradiation. Moreover, surface capacitance measurements showed that the Al overlayer was indeed passivating the surface states. We also shed light on the deposition of an Al overlayer on the surface of BiVO4, by investigating the process on model BiVO4 powders. This study presents useful, previously unreported information about the surface chemistry of BiVO4 based on experimental methods and gives unique insights on the characterization of the BiVO4 surface. The existence of surface reactive sites on BiVO4 was confirmed and quantified (1.5 reactive sites/nm2) via chemical titration.
Kristine Rodulfo Tolod; Tapish Saboo; Simelys Hernández; Hilmar Guzmán; Micaela Castellino; Rowshanak Irani; Peter Bogdanoff; Fatwa F. Abdi; Elsje Alessandra Quadrelli; Nunzio Russo. Insights on the surface chemistry of BiVO4 photoelectrodes and the role of Al overlayers on its water oxidation activity. Applied Catalysis A: General 2020, 605, 117796 .
AMA StyleKristine Rodulfo Tolod, Tapish Saboo, Simelys Hernández, Hilmar Guzmán, Micaela Castellino, Rowshanak Irani, Peter Bogdanoff, Fatwa F. Abdi, Elsje Alessandra Quadrelli, Nunzio Russo. Insights on the surface chemistry of BiVO4 photoelectrodes and the role of Al overlayers on its water oxidation activity. Applied Catalysis A: General. 2020; 605 ():117796.
Chicago/Turabian StyleKristine Rodulfo Tolod; Tapish Saboo; Simelys Hernández; Hilmar Guzmán; Micaela Castellino; Rowshanak Irani; Peter Bogdanoff; Fatwa F. Abdi; Elsje Alessandra Quadrelli; Nunzio Russo. 2020. "Insights on the surface chemistry of BiVO4 photoelectrodes and the role of Al overlayers on its water oxidation activity." Applied Catalysis A: General 605, no. : 117796.
The discovery of novel catalytic materials showing unprecedented properties and improved functionalities represents a major challenge to design advanced oxidation processes for wastewater purification. In this work, antimony (Sb) doping is proposed as a powerful approach for enhancing the photo- and piezocatalytic performances of piezoelectric zinc oxide (ZnO) thin films. To investigate the role played by the dopant, the degradation of Rhodamine-β (Rh-β), a dye pollutant widely present in natural water sources, is studied when the catalyst is irradiated by ultraviolet (UV) light or ultrasound (US) waves. Depending on the doping level, the structural, optical and ferroelectric properties of the catalyst can be properly set to maximize the dye degradation efficiency. Independently of the irradiation source, the fastest and complete dye degradation is observed in presence of the doped catalyst and for an optimal amount of the inserted dopant. Among ZnO:Sb samples, the most doped one (5 at.%) shows improved UV light absorption and photocatalytic properties. Conversely, the piezocatalytic efficiency is maximized using the lowest Sb amount (1 at.%). The superior ferroelectric polarization observed in this case highly favors the adsorption of electrically-charged species, in particular of the dye in the protonated form (Rh-β+) and of OH-, to the catalyst surface and the production of hydroxyl radicals responsible for dye degradation.
Marco Laurenti; Nadia Garino; Giancarlo Canavese; Simelys Hernandéz; Valentina Cauda. Piezo- and Photocatalytic Activity of Ferroelectric ZnO:Sb Thin Films for the Efficient Degradation of Rhodamine-β dye Pollutant. ACS Applied Materials & Interfaces 2020, 12, 25798 -25808.
AMA StyleMarco Laurenti, Nadia Garino, Giancarlo Canavese, Simelys Hernandéz, Valentina Cauda. Piezo- and Photocatalytic Activity of Ferroelectric ZnO:Sb Thin Films for the Efficient Degradation of Rhodamine-β dye Pollutant. ACS Applied Materials & Interfaces. 2020; 12 (23):25798-25808.
Chicago/Turabian StyleMarco Laurenti; Nadia Garino; Giancarlo Canavese; Simelys Hernandéz; Valentina Cauda. 2020. "Piezo- and Photocatalytic Activity of Ferroelectric ZnO:Sb Thin Films for the Efficient Degradation of Rhodamine-β dye Pollutant." ACS Applied Materials & Interfaces 12, no. 23: 25798-25808.
Solutions of biobased ionic liquids (ILs) for recovering CO2 from industrial flue gas are investigated. Four CO2 task‐specific choline‐based amino acids ([Cho][AA]): Alanine, Glycine, and, for the first time, Proline and Serine are tested. The drawbacks related to the high viscosity of these ILs are limited by applying dimethyl sulfoxide (DMSO) as a solvent, which is chosen because it is a polar aprotic liquid with a low toxicity, low vapor pressure, and relatively low price. The choline‐based amino acids synthesized in this study have good absorption capacities (up to 0.3 mol CO2/mol IL, with only 12.5 wt% IL in DMSO) that represent the best performance of CO2 task‐specific IL solutions to date. These solutions are competitive due to their low cost, low environmental impact, easy processability (due to their low viscosity) and good regenerability for the production and storage of pure CO2.
Elahe Davarpanah; Simelys Hernández; Giulio Latini; Candido Fabrizio Pirri; Sergio Bocchini. Enhanced CO 2 Absorption in Organic Solutions of Biobased Ionic Liquids. Advanced Sustainable Systems 2019, 4, 1 .
AMA StyleElahe Davarpanah, Simelys Hernández, Giulio Latini, Candido Fabrizio Pirri, Sergio Bocchini. Enhanced CO 2 Absorption in Organic Solutions of Biobased Ionic Liquids. Advanced Sustainable Systems. 2019; 4 (1):1.
Chicago/Turabian StyleElahe Davarpanah; Simelys Hernández; Giulio Latini; Candido Fabrizio Pirri; Sergio Bocchini. 2019. "Enhanced CO 2 Absorption in Organic Solutions of Biobased Ionic Liquids." Advanced Sustainable Systems 4, no. 1: 1.
In this work, the synthesis of cheap BiVO4 photoanodes for the photoelectrochemical water splitting reaction was optimized via the scalable thin film electrodeposition method. Factors affecting the photoelectrochemical activity, such as the electrodeposition time, the ratio of the Bi-KI to benzoquinone-EtOH in the deposition bath, and the calcination temperature, have been investigated by using the Central Composite Design of Experiments. Pristine monoclinic scheelite BiVO4 photoanodes having a photocurrent density of 0.45 ± 0.05 mA/cm2 at 1.23 V vs RHE have been obtained. It was shown that a high photocurrent density is generally dictated by the following physico-chemical properties: a higher crystallite size, optimal thickness and a porous morphology, which give rise to a low charge transfer resistance, low onset potential and a high donor density. Moreover, to the best of our knowledge, this is the first report on the depth profile XPS analysis performed in BiVO4 photoanodes made by electrodeposition technique, from which it was concluded that the surface V species exist as V4+ while the bulk V species are V5+. The V4+ induces a higher amount of surface oxygen vacancies, which was found to be beneficial for the photoactivity.
Kristine Rodulfo Tolod; Simelys Hernández; Micaela Castellino; Fabio Alessandro Deorsola; Elahe Davarpanah; Nunzio Russo. Optimization of BiVO4 photoelectrodes made by electrodeposition for sun-driven water oxidation. International Journal of Hydrogen Energy 2019, 45, 605 -618.
AMA StyleKristine Rodulfo Tolod, Simelys Hernández, Micaela Castellino, Fabio Alessandro Deorsola, Elahe Davarpanah, Nunzio Russo. Optimization of BiVO4 photoelectrodes made by electrodeposition for sun-driven water oxidation. International Journal of Hydrogen Energy. 2019; 45 (1):605-618.
Chicago/Turabian StyleKristine Rodulfo Tolod; Simelys Hernández; Micaela Castellino; Fabio Alessandro Deorsola; Elahe Davarpanah; Nunzio Russo. 2019. "Optimization of BiVO4 photoelectrodes made by electrodeposition for sun-driven water oxidation." International Journal of Hydrogen Energy 45, no. 1: 605-618.
Huge efforts have been done in the last years on electrochemical and photoelectrochemical reduction of CO2 to offer a sustainable route to recycle CO2. A promising route is to electrochemically reduce CO2 into CO which, by combination with hydrogen, can be used as a feedstock to different added-value products or fuels. Herein, perpendicular oriented TiO2 nanotubes (NTs) on the electrode plate were grown by anodic oxidation of titanium substrate and then decorated by a low loading of silver nanoparticles deposited by sputtering (i.e. Ag/TiO2 NTs). Due to their quasi one-dimensional arrangement, TiO2 NTs are able to provide higher surface area for Ag adhesion and superior electron transport properties than other Ti substrates (e.g. Ti foil and TiO2 nanoparticles), as confirmed by electrochemical (CV, EIS, electrochemical active surface area) and chemical/morphological analysis (FESEM, TEM, EDS). These characteristics together with the role of the TiO2 NTs to enhance the stability of CO2·- intermediate formed due to titania redox couple (TiIV/TiIII) lead to an improvement of the CO production in the Ag/TiO2 NTs electrodes. Particular attention has been devoted to reduce the loading of noble metal in the electrode(14.5 %w/%w) and to increase the catalysts active surface area in order to decrease the required overpotential.
M. Amin Farkhondehfal; S. Hernández; M. Rattalino; M. Makkee; A. Lamberti; A. Chiodoni; K. Bejtka; A. Sacco; F.C. Pirri; N. Russo. Syngas production by electrocatalytic reduction of CO2 using Ag-decorated TiO2 nanotubes. International Journal of Hydrogen Energy 2019, 45, 26458 -26471.
AMA StyleM. Amin Farkhondehfal, S. Hernández, M. Rattalino, M. Makkee, A. Lamberti, A. Chiodoni, K. Bejtka, A. Sacco, F.C. Pirri, N. Russo. Syngas production by electrocatalytic reduction of CO2 using Ag-decorated TiO2 nanotubes. International Journal of Hydrogen Energy. 2019; 45 (50):26458-26471.
Chicago/Turabian StyleM. Amin Farkhondehfal; S. Hernández; M. Rattalino; M. Makkee; A. Lamberti; A. Chiodoni; K. Bejtka; A. Sacco; F.C. Pirri; N. Russo. 2019. "Syngas production by electrocatalytic reduction of CO2 using Ag-decorated TiO2 nanotubes." International Journal of Hydrogen Energy 45, no. 50: 26458-26471.
In this paper we present an easy, quick and scalable route, based on anodic oxidation, for the preparation of mesoporous SnO2 as an efficient electrocatalyst for the CO2 reduction reaction (CO2RR). Crystallographically interconnected SnO2 nanocrystals with abundant grain boundaries, high specific surface area and easily accessible porosity result to be active and selective for the CO2RR. This electrocatalyst shows faradaic efficiency (FE) of about 95% at -0.97 V and -1.06 V vs. reversible hydrogen electrode (RHE) towards the formation of predominant HCOOH and minor CO. A peak FE value of 82 % for the HCOOH production is obtained at -1.06 V vs. RHE. High HCOOH partial current densities of 10.2 mA cm-2 and 15.3 mA cm-2 are observed at -0.97 V and -1.15 V vs. RHE, respectively. Thorough electrochemical characterizations demonstrate that the synthesized SnO2-based gas diffusion electrode allows efficient diffusion of CO2 even at high kinetics, due to the highly open porous structure. The good understanding of the catalyst behavior is achieved also after the electrode testing and it shows that the proposed preparation route results in a stable and durable material. The here reported promising results can be exploited for developing high-performance and sustainable electrocatalysts with a high potentiality to be implemented in real CO2 conversion devices.
Katarzyna Bejtka; Juqin Zeng; Adriano Sacco; Micaela Castellino; Simelys Hernández; M. Amin Farkhondehfal; Umberto Savino; Simone Ansaloni; Candido Fabrizio Pirri; Angelica Chiodoni. Chainlike Mesoporous SnO2 as a Well-Performing Catalyst for Electrochemical CO2 Reduction. ACS Applied Energy Materials 2019, 2, 3081 -3091.
AMA StyleKatarzyna Bejtka, Juqin Zeng, Adriano Sacco, Micaela Castellino, Simelys Hernández, M. Amin Farkhondehfal, Umberto Savino, Simone Ansaloni, Candido Fabrizio Pirri, Angelica Chiodoni. Chainlike Mesoporous SnO2 as a Well-Performing Catalyst for Electrochemical CO2 Reduction. ACS Applied Energy Materials. 2019; 2 (5):3081-3091.
Chicago/Turabian StyleKatarzyna Bejtka; Juqin Zeng; Adriano Sacco; Micaela Castellino; Simelys Hernández; M. Amin Farkhondehfal; Umberto Savino; Simone Ansaloni; Candido Fabrizio Pirri; Angelica Chiodoni. 2019. "Chainlike Mesoporous SnO2 as a Well-Performing Catalyst for Electrochemical CO2 Reduction." ACS Applied Energy Materials 2, no. 5: 3081-3091.
TiO2 nanoparticles containing 0.0, 1.0, 5.0, and 10.0 wt.% Mo were prepared by a reverse micelle template assisted sol–gel method allowing the dispersion of Mo atoms in the TiO2 matrix. Their textural and surface properties were characterized by means of X-ray powder diffraction, micro-Raman spectroscopy, N2 adsorption/desorption isotherms at −196 °C, energy dispersive X-ray analysis coupled to field emission scanning electron microscopy, X-ray photoelectron spectroscopy, diffuse reflectance UV–Vis spectroscopy, and ζ-potential measurement. The photocatalytic degradation of Rhodamine B (under visible light and low irradiance) in water was used as a test reaction as well. The ensemble of the obtained experimental results was analyzed in order to discover the actual state of Mo in the final materials, showing the occurrence of both bulk doping and Mo surface species, with progressive segregation of MoOx species occurring only at a higher Mo content.
Roberto Nasi; Serena Esposito; Francesca S. Freyria; Marco Armandi; Tanveer A. Gadhi; Simelys Hernandez; Paola Rivolo; Nicoletta Ditaranto; Barbara Bonelli. Application of Reverse Micelle Sol–Gel Synthesis for Bulk Doping and Heteroatoms Surface Enrichment in Mo-Doped TiO2 Nanoparticles. Materials 2019, 12, 937 .
AMA StyleRoberto Nasi, Serena Esposito, Francesca S. Freyria, Marco Armandi, Tanveer A. Gadhi, Simelys Hernandez, Paola Rivolo, Nicoletta Ditaranto, Barbara Bonelli. Application of Reverse Micelle Sol–Gel Synthesis for Bulk Doping and Heteroatoms Surface Enrichment in Mo-Doped TiO2 Nanoparticles. Materials. 2019; 12 (6):937.
Chicago/Turabian StyleRoberto Nasi; Serena Esposito; Francesca S. Freyria; Marco Armandi; Tanveer A. Gadhi; Simelys Hernandez; Paola Rivolo; Nicoletta Ditaranto; Barbara Bonelli. 2019. "Application of Reverse Micelle Sol–Gel Synthesis for Bulk Doping and Heteroatoms Surface Enrichment in Mo-Doped TiO2 Nanoparticles." Materials 12, no. 6: 937.
In this work, it is proposed an environmental friendly sonophotocatalytic approach to efficiently treat polluted waters from industrial dyes exploiting ZnO micro- and nano-materials. For the first time, we deeply investigated the generation of reactive oxygen species (ROS) under ultrasound stimulation of different ZnO structures by Electron Paramagnetic Resonance Spectroscopy (EPR). Indeed, five zinc oxide (ZnO) micro- and nano-structures, i.e. Desert Roses (DRs), Multipods (MPs), Microwires (MWs), Nanoparticles (NPs) and Nanowires (NWs), were studied for the Rhodamine B (RhB) sonodegradation under ultrasonic irradiation. The DRs microparticles demonstrated the best sonocatalytic performance (100% degradation of RhB in 180 min) and the highest OH radicals generation under ultrasonic irradiation. Strikingly, the coupling of ultrasound and sun-light irradiation in a sonophotodegradation approach led to 100% degradation efficiency, i.e. color reduction, of RhB in just 10 min, revealing a great positive synergy between the photocatalytic and sonocatalytic mechanisms. The RhB sonophotocatalytic degradation was also evaluated at different initial dye concentrations and with the presence of anions in solution. It was demonstrated a good stability over repeated cycles of dye treatment, which probe the applicability of this technique with industrial effluents. In conclusion, sonophotocatalytic degradation synergizing sunlight and ultrasound in the presence of DRs microparticles shows a great potential and a starting point to investigate further the efficient treatment of organic dyes in wastewater.
Carmine Lops; Andrea Ancona; Katia Di Cesare; Bianca Dumontel; Nadia Garino; Giancarlo Canavese; Simelys Hérnandez; Valentina Cauda. Sonophotocatalytic degradation mechanisms of Rhodamine B dye via radicals generation by micro- and nano-particles of ZnO. Applied Catalysis B: Environmental 2018, 243, 629 -640.
AMA StyleCarmine Lops, Andrea Ancona, Katia Di Cesare, Bianca Dumontel, Nadia Garino, Giancarlo Canavese, Simelys Hérnandez, Valentina Cauda. Sonophotocatalytic degradation mechanisms of Rhodamine B dye via radicals generation by micro- and nano-particles of ZnO. Applied Catalysis B: Environmental. 2018; 243 ():629-640.
Chicago/Turabian StyleCarmine Lops; Andrea Ancona; Katia Di Cesare; Bianca Dumontel; Nadia Garino; Giancarlo Canavese; Simelys Hérnandez; Valentina Cauda. 2018. "Sonophotocatalytic degradation mechanisms of Rhodamine B dye via radicals generation by micro- and nano-particles of ZnO." Applied Catalysis B: Environmental 243, no. : 629-640.
A tin-modified copper foam for the efficient and selective reduction of CO2 to CO is reported. We employ a cost-efficient electrodeposition route to form a three-dimensional porous dendrite architecture, in which each dendrite possesses a copper core and a copper oxide/tin oxide shell. The sparse tin species on the electrode surface play a key role to achieve excellent faradaic efficiencies for CO formation with a maximum value of 94 %. We demonstrate high CO partial current densities of 4.7 mA cm-2 and 7.9 mA cm-2 at applied potentials of -0.8 V and -1.1 V vs. the reversible hydrogen electrode, respectively. The high activity for electrochemical CO2 reduction is attributed to the unique hierarchical porous structure, which offers abundant electrochemically active sites and facilitates mass transport.
Juqin Zeng; Katarzyna Bejtka; Wenbo Ju; Micaela Castellino; Angelica Chiodoni; Adriano Sacco; M. Amin Farkhondehfal; Simelys Hernández; Daniel Rentsch; Corsin Battaglia; Candido F. Pirri. Advanced Cu-Sn foam for selectively converting CO2 to CO in aqueous solution. Applied Catalysis B: Environmental 2018, 236, 475 -482.
AMA StyleJuqin Zeng, Katarzyna Bejtka, Wenbo Ju, Micaela Castellino, Angelica Chiodoni, Adriano Sacco, M. Amin Farkhondehfal, Simelys Hernández, Daniel Rentsch, Corsin Battaglia, Candido F. Pirri. Advanced Cu-Sn foam for selectively converting CO2 to CO in aqueous solution. Applied Catalysis B: Environmental. 2018; 236 ():475-482.
Chicago/Turabian StyleJuqin Zeng; Katarzyna Bejtka; Wenbo Ju; Micaela Castellino; Angelica Chiodoni; Adriano Sacco; M. Amin Farkhondehfal; Simelys Hernández; Daniel Rentsch; Corsin Battaglia; Candido F. Pirri. 2018. "Advanced Cu-Sn foam for selectively converting CO2 to CO in aqueous solution." Applied Catalysis B: Environmental 236, no. : 475-482.
In this work, nanostructured rare-earth-doped zirconia was successfully synthesized, through a simple hydrothermal method, with a rare-earth oxide (REO)-based content varying from 0.5 to 5% molar (REO = CeO2; Er2O3). The samples were characterized by using several techniques, such as X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, diffuse reflectance spectroscopy. The photoactivity of the samples was tested under irradiation with simulated solar light by both the spin trapping technique, using DMPO (5,5-dimethyl-1-pyrroline-N-oxide) as spin trapping agent, and by the photodegradation of Rhodamine B, a common textile dye. All the doped samples resulted more active than the bare zirconia, and the correlation between the physical-chemical properties and the photoactivity of the materials has been investigated.
Chiara Gionco; Simelys Hernández; Micaela Castellino; Tanveer Ahmed Gadhi; José Alejandro Muñoz-Tabares; Erik Cerrato; Alberto Tagliaferro; Nunzio Russo; Maria Cristina Paganini. Synthesis and characterization of Ce and Er doped ZrO2 nanoparticles as solar light driven photocatalysts. Journal of Alloys and Compounds 2018, 775, 896 -904.
AMA StyleChiara Gionco, Simelys Hernández, Micaela Castellino, Tanveer Ahmed Gadhi, José Alejandro Muñoz-Tabares, Erik Cerrato, Alberto Tagliaferro, Nunzio Russo, Maria Cristina Paganini. Synthesis and characterization of Ce and Er doped ZrO2 nanoparticles as solar light driven photocatalysts. Journal of Alloys and Compounds. 2018; 775 ():896-904.
Chicago/Turabian StyleChiara Gionco; Simelys Hernández; Micaela Castellino; Tanveer Ahmed Gadhi; José Alejandro Muñoz-Tabares; Erik Cerrato; Alberto Tagliaferro; Nunzio Russo; Maria Cristina Paganini. 2018. "Synthesis and characterization of Ce and Er doped ZrO2 nanoparticles as solar light driven photocatalysts." Journal of Alloys and Compounds 775, no. : 896-904.
In the present work, the activity of Ce and Er-doped ZrO2 nanopowders for sun-driven photocatalytic water oxidation has been investigated. ZrO2 powders with tunable amounts of tetragonal, monoclinic and cubic polymorphs have been synthesized by introducing Ce and Er (from 0.5 to 10 mol % on an oxide basis) through hydrothermal method. The aim of this work is to investigate the role of rare earth (RE) ions rich of electrons (Er3+) and with entirely empty levels (Ce4+) in the ZrO2 matrix for the sun-driven photocatalytic water oxidation reaction. The samples have been characterized by means of UV-Vis spectroscopy, X-Ray diffraction (XRD), N2 adsorption, X-ray photoelectron spectrophotometry (XPS) and transmission electronic microscopy (TEM) with energy dispersive spectroscopy (EDS). With respect to the bare ZrO2 mainly containing monoclinic (m-) phase, an increasing amount of rare-earth (RE) dopant was found to improve the specific BET surface area and to stabilize the tetragonal (t-) or cubic (c-) polymorphs of ZrO2 at room temperature. XRD data confirmed that dopants were mainly inserted in the t-ZrO2 phase. The photocatalytic O2 evolution from water under AM 1.5 G simulated sunlight illumination of the prepared samples have been correlated with their optical, structural and chemical properties. The effect of the dopant concentration on the chemical-physical and photocatalytic properties of the Er- and Ce-doped ZrO2 materials was elucidated. The samples with 5% of RE oxide were the most active, i.e., three times more than pure zirconia. Their superior photocatalytic activity was found to be mainly correlated to two factors: (i) an optimal surface concentration of RE ions of about 3.7%, which increased charge carriers separation in the photocatalysts surface due more superficial defects of the t-ZrO2 and a higher surface area, thus enhancing the reaction kinetics, (ii) a controlled amount of monoclinic vs. tetragonal (or cubic) polymorphs of zirconia with an optimum ratio of about 70/30 of t-ZrO2/m-ZrO2. Instead, the increased ability of the RE-doped ZrO2 to harvest visible light was found to have a secondary role on the photocatalytic activity of the Ce-doped ZrO2 material.
Simelys Hernández; Chiara Gionco; Thomas Husak; Micaela Castellino; José A. Muñoz-Tabares; Kristine R. Tolod; Elio Giamello; Maria C. Paganini; Nunzio Russo. Insights Into the Sunlight-Driven Water Oxidation by Ce and Er-Doped ZrO2. Frontiers in Chemistry 2018, 6, 1 .
AMA StyleSimelys Hernández, Chiara Gionco, Thomas Husak, Micaela Castellino, José A. Muñoz-Tabares, Kristine R. Tolod, Elio Giamello, Maria C. Paganini, Nunzio Russo. Insights Into the Sunlight-Driven Water Oxidation by Ce and Er-Doped ZrO2. Frontiers in Chemistry. 2018; 6 ():1.
Chicago/Turabian StyleSimelys Hernández; Chiara Gionco; Thomas Husak; Micaela Castellino; José A. Muñoz-Tabares; Kristine R. Tolod; Elio Giamello; Maria C. Paganini; Nunzio Russo. 2018. "Insights Into the Sunlight-Driven Water Oxidation by Ce and Er-Doped ZrO2." Frontiers in Chemistry 6, no. : 1.
We report on a fast and simple protocol for the electrodeposition of Fe-MnOx films used as catalysts for the water oxidation (WO) reaction at neutral pH, and showing the beneficial effect of iron in terms of both activity and stability of the catalyst. While most electrodeposited MnOx WO catalysts are obtained starting from Mn(II) precursors, the proposed protocol consists in the galvanostatic cathodic deposition of Fe-MnOx onto conductive FTO glasses, using KMnO4 and Fe(NO3)3 as Mn and Fe precursors, respectively. In the absence of Fe, the Tafel slope drastically increases from 103 to 270 mV dec−1 when passing from low to high overpotentials. The slope change, instead, is progressively reduced when the Fe precursor is added to the deposition solution and a constant slope of 105 mV dec−1 is obtained in the whole overpotential range with an optimal Fe concentration of 1.00 mM, Accordingly, Electrochemical Impedance Spectroscopy (EIS) shows that Fe addition improves both charge transfer and transport properties of the electrodeposited films. In particular, a five-fold decrease in charge transfer resistance at the catalyst/electrolyte interface was observed, suggesting a more facile oxygen evolving kinetics for Fe containing samples. Furthermore, the lower the iron content, the lower the film stability, as pointed out by chronopotentiometric measurements, and confimed by FESEM analysis and EIS as measured both before and after water electrolysis experiments. To establish structure activity relationships, an extended characterization of the electrodeposited films was carried out by means of Raman Microscopy, Transmission Electron Microscopy, UV–vis and X-ray Photoelectron Spectroscopies. The ensemble of the characterization results suggests that Fe3+ ions are actually incorporated within the electrodeposited film, with limited effects on the final Fe-MnOx structure, consisting in a defective MnO2 birnessite-type structure with significant fraction of surface Mn3+ species.
Marco Etzi Coller Pascuzzi; Elizabeth Selinger; Adriano Sacco; Micaela Castellino; Paola Rivolo; Simelys Hernández; Gregory Lopinski; Isaac Tamblyn; Roberto Nasi; Serena Esposito; Maela Manzoli; Barbara Bonelli; Marco Armandi. Beneficial effect of Fe addition on the catalytic activity of electrodeposited MnOx films in the water oxidation reaction. Electrochimica Acta 2018, 284, 294 -302.
AMA StyleMarco Etzi Coller Pascuzzi, Elizabeth Selinger, Adriano Sacco, Micaela Castellino, Paola Rivolo, Simelys Hernández, Gregory Lopinski, Isaac Tamblyn, Roberto Nasi, Serena Esposito, Maela Manzoli, Barbara Bonelli, Marco Armandi. Beneficial effect of Fe addition on the catalytic activity of electrodeposited MnOx films in the water oxidation reaction. Electrochimica Acta. 2018; 284 ():294-302.
Chicago/Turabian StyleMarco Etzi Coller Pascuzzi; Elizabeth Selinger; Adriano Sacco; Micaela Castellino; Paola Rivolo; Simelys Hernández; Gregory Lopinski; Isaac Tamblyn; Roberto Nasi; Serena Esposito; Maela Manzoli; Barbara Bonelli; Marco Armandi. 2018. "Beneficial effect of Fe addition on the catalytic activity of electrodeposited MnOx films in the water oxidation reaction." Electrochimica Acta 284, no. : 294-302.
Low-cost manganese oxide, MnOx-based electrocatalysts, containing α-MnO2 and mixed α-Mn2O3/α-MnO2 phases, were synthesized by scalable anodic and cathodic electrodeposition methods, respectively. Their morphological and chemical composition were characterized by means of Field Emission Scanning Electronic Microscopy (FESEM), X-Ray Diffraction (XRD) and X-ray Photoelectron Spectroscopy (XPS). These electrodes were tested for the electro-oxidation of a recalcitrant molecule (i.e. phenol) in a lab-scale high temperature and high pressure (HTHP) batch electrocatalytic reactor. Their electrocatalytic activity was compared with that of state-of-the-art anodes for phenol electro-oxidation: antimony-doped tin oxide (SnO2–Sb5+) and ruthenium oxide (RuO2): first, under standard ambient conditions, and then, under the conditions of a Polymeric Electrolyte Membrane (PEM) electrolyzer (i.e. 85 °C and 30 bar) and of mild Catalytic Wet Air Oxidation (CWAO, i.e. 150 °C and 30 bar). Both reaction time and current density were varied to investigate their effect in the performances of the system as well as on the reaction mechanism. Both MnOx electrodes reported enhanced conversion efficiencies, up to ∼75%, at the highest pressure and temperature, and at the lowest applied current density, which influenced the process by improving dissolution of the O2 evolved, the reaction kinetics and thermodynamics, and by minimizing irreversibilities, respectively. The here reported MnOx films achieved conversion and mineralization efficiencies comparable to Sb-SnO2 (that is the more toxic) and RuO2 (that is more expensive) materials, operating under mild CWAO operation conditions, which demonstrate the potential of the electrocatalytic HTHP process as a sustainable advanced oxidation technology for wastewater treatment or electrosynthesis applications.
Andrea Massa; Simelys Hernández; Simone Ansaloni; Micaela Castellino; Nunzio Russo; Debora Fino. Enhanced electrochemical oxidation of phenol over manganese oxides under mild wet air oxidation conditions. Electrochimica Acta 2018, 273, 53 -62.
AMA StyleAndrea Massa, Simelys Hernández, Simone Ansaloni, Micaela Castellino, Nunzio Russo, Debora Fino. Enhanced electrochemical oxidation of phenol over manganese oxides under mild wet air oxidation conditions. Electrochimica Acta. 2018; 273 ():53-62.
Chicago/Turabian StyleAndrea Massa; Simelys Hernández; Simone Ansaloni; Micaela Castellino; Nunzio Russo; Debora Fino. 2018. "Enhanced electrochemical oxidation of phenol over manganese oxides under mild wet air oxidation conditions." Electrochimica Acta 273, no. : 53-62.