Felipe Martins de Souza

Mr. Felipe Martins de Souza

Pittsburg State University, Pittsburg, California, USA

Research Focus & Metrics

Academic Career Length

5Years (2022-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
31 May 2022 in Energies
Verified
Journal Article
Open access
PDF file
KMKwadwo Mensah-Darkwa
Kwadwo Mensah-Darkwa
DADaniel Nframah Ampong
Daniel Nframah Ampong
EAEmmanuel Agyekum
Emmanuel Agyekum
FSFelipe Martins de Souza
Felipe Martins de Souza
Ram K. GuptaRam K. Gupta
Ram K. Gupta
Energy storage has become increasingly important as a study area in recent decades. A growing number of academics are focusing their attention on developing and researching innovative materials for use in energy storage systems to promote sustainable development goals. This is due to the finite supply of traditional energy sources, such as oil, coal, and natural gas, and escalating regional tensions. Because of these issues, sustainable renewable energy sources have been touted as an alternative to nonrenewable fuels. Deployment of renewable energy sources requires efficient and reliable energy storage devices due to their intermittent nature. High-performance electrochemical energy storage technologies with high power and energy densities are heralded to be the next-generation storage devices. Transition metal chalcogenides (TMCs) have sparked interest among electrode materials because of their intriguing electrochemical properties. Researchers have revealed a variety of modifications to improve their electrochemical performance in energy storage. However, a stronger link between the type of change and the resulting electrochemical performance is still desired. This review examines the synthesis of chalcogenides for electrochemical energy storage devices, their limitations, and the importance of the modification method, followed by a detailed discussion of several modification procedures and how they have helped to improve their electrochemical performance. We also discussed chalcogenides and their composites in batteries and supercapacitors applications. Furthermore, this review discusses the subject’s current challenges as well as potential future opportunities.

3 December 2022 in Polymers
Verified
Journal Article
Open access
PDF file
MAMagdalene Anima Asare
Magdalene Anima Asare
PKPrashant Kote
Prashant Kote
SCSAHILKUMAR ASHVINKUMAR CHAUDHARY
SAHILKUMAR ASHVINKUMAR CHAUDHARY
FSFelipe Martins de Souza
Felipe Martins de Souza
Ram K. GuptaRam K. Gupta
Ram K. Gupta
Currently, polyurethane (PU) manufacturers seek green alternatives for sustainable production. In this work, sunflower oil is studied as a replacement and converted to a reactive form through epoxidation and oxirane opening to produce rigid PU foams. Confirmatory tests such as Fourier-transform infrared spectroscopy (FT-IR), gel permeation chromatography (GPC), and hydroxyl value among others were performed to characterize the synthesized polyol. Despite the versatility of rigid PU foams, they are highly flammable, which makes eco-friendly flame retardants (FRs) desired. Herein, expandable graphite (EG) and dimethyl methyl phosphonate (DMMP), both non-halogenated FR, were incorporated under different concentrations to prepare rigid PU foams. Their effects on the physio-mechanical and fire-quenching properties of the sunflower oil-based PU foams were elucidated. Thermogravimetric and compression analysis showed that these foams presented appreciable compressive strength along with good thermal stability. The closed-cell contents (CCC) were around 90% for the EG-containing foams and suffered a decrease at higher concentrations of DMMP to 72%. The burning test showed a decrease in the foam’s flammability as the neat foam had a burning time of 80 s whereas after the addition of 13.6 wt.% of EG and DMMP, separately, there was a decrease to 6 and 2 s, respectively. Hence, our research suggested that EG and DMMP could be a more viable alternative to halogen-based FR for PU foams. Additionally, the adoption of sunflower polyol yielded foams with results comparable to commercial ones.

17 November 2022 in Polymers
Verified
Journal Article
Open access
PDF file
VSvishwa D. suthar
vishwa D. suthar
MAMagdalene Anima Asare
Magdalene Anima Asare
FSFelipe Martins de Souza
Felipe Martins de Souza
Ram K. GuptaRam K. Gupta
Ram K. Gupta
Sunflower oil was used for the synthesis of a polyol via an epoxidation reaction followed by a ring-opening reaction. The successful synthesis of the sunflower oil-based polyol (SFO polyol) was demonstrated through structural characterizations and wet-chemistry analysis. Bio-based polyurethane (BPU) films were fabricated using synthesized polyol and diisocyanate. Various amounts of graphene oxide (GO) and reduced graphene oxide (rGO) were added separately to see their effect on the physicomechanical and thermal properties of BPU films. Several tests, such as thermogravimetric analysis, tensile strength, dynamic mechanical analysis, hardness, flexural strength, and the water contact angle, were performed to evaluate the effect of GO and rGO on the properties of the BPU films. Some of the analyses of the BPU films demonstrated an improvement in the mechanical properties, for example, the tensile strength increased from 22.5 to 26 MPa with the addition of only 0.05 wt.% GO. The storage modulus improved from 900 to 1000 and 1700 MPa after the addition of 0.02 and 0.05 wt.% GO, respectively. This study shows that a small amount of GO and rGO could improve the properties of BPU films, making them suitable for use in coating industries.

2 August 2022
Verified
Book Chapter
Closed access
PDF file
SBShiva Bhardwaj
Shiva Bhardwaj
FSFelipe Martins de Souza
Felipe Martins de Souza
RGRam K. Gupta
Ram K. Gupta


14 October 2022
Verified
Book Chapter
Closed access
PDF file
FSFelipe Martins de Souza
Felipe Martins de Souza
PKProf. Dr. Anuj Kumar
Prof. Dr. Anuj Kumar
Ram K. GuptaRam K. Gupta
Ram K. Gupta