A method for the preparation of transparent superhydrophobic silica coatings on glass substrates via aerosol‐assisted chemical vapour deposition (AACVD) is described. A multi-layer process to produce dual scale silica nanoparticles films, by using different functional alkoxysilanes was investigated. A first layer of 3-methacryloxypropyltrimethoxysilane (MPS) and a second layer of tetraethylorthosilicate (TEOS) were deposited at different temperatures to generate micro and nano particles of silica. Finally, a layer of perfluorooctyltriethoxysilane was deposited on top of the two layers to achieve superhydrophobicity. The transparent superhydrophobic film showed transparency of 90% in the visible light region with a static water contact angle of 165° and a sliding angle lower than 1°. Various durability tests were performed on the transparent superhydrophobic film, showing a constant water repellency after corrosion and organic solvents tests, strong resistance under UV light, and thermal stability up to 400 °C. Sandpaper mechanical robustness durability test showed superhydrophobicity for up to 5 rubbing cycles. In this study, a novel strategy to achieve highly transparent superhydrophobic glass surfaces using AACVD of alkoxysilanes, to produce surfaces with excellent durability is described. This shows great potential to obtain silica superhydrophobic films for large–scale applications.
Metal organic frameworks (MOFs) are a family of crystalline porous materials which attracts much attention for their possible application in energy electrochemical conversion and storage devices due to their ordered structures characterized by large surface areas and the presence in selected cases of a redox-active porous skeleton. Their synthetic versatility and relevant host-guest chemistry make them suitable platform for use in stable and flexible conductive materials. In this review we summarize the most recent results obtained in this field, by analyzing the use of MOFs in fuel and solar cells with special emphasis on PEMFCs and PSCs, their application in supercapacitors and the employment in batteries by differentiating Li-, Na- and other metal ion-batteries. Finally, an overview of the water splitting reaction MOF-catalyzed is also reported.
Metal–organic frameworks (MOFs) are a family of porous crystalline materials that serve in some cases as versatile platforms for catalysis. In this review, we overview the recent developments about the use of these species as heterogeneous catalysts in olefin epoxidation and carbon dioxide cycloaddition. We report the most important results obtained in this field relating them to the presence of specific organic linkers, metal nodes or clusters and mixed-metal species. Recent advances obtained with MOF nanocomposites were also described. Finally we compare the results and summarize the major insights in specific Tables, outlining the major challenges for this emerging field. This work could promote new research aimed at producing coordination polymers and MOFs able to catalyse a broader range of CO2 consuming reactions.
Sodium‐ion batteries (SIBs) represent a potential alternative to lithium‐ion batteries in large‐scale energy storage applications. To improve the sustainability of SIBs, the utilization of anode carbonaceous materials produced from biomass and the selection of a bio‐based binder allowing an aqueous electrode processing are fundamental. Herein, corncobs are used as raw material for the preparation of hard carbon and it is also used as cellulose sources for the synthesis of carboxymethyl cellulose (CMC) binder. The corncob‐derived electrodes deliver a high discharge capacity of around 264 mAhg−1 at 1 C (300 mAg−1), with promising capacity retention (84 % after 100 cycles) and good rate capability. Additionally, this work expands the fundamental insight of the sodium storage behavior of Hard Carbons through an electrochemical approach, suggesting that the reaction mechanism is controlled by capacitive process in the sloping voltage region, while the diffusion‐controlled intercalation is the predominant process in the low‐voltage plateau.