Discipline: Chemistry and Chemical Sciences
Subcategory: Materials Science
Abniel Machín-De Jesús - Universidad del Turabo
Co-Author(s): Juan C. Arango and Francisco Márquez, Universidad del Turabo, Gurabo, PR Carmen Morant, Universidad Autónoma de Madrid, Madrid, Spain
In order to avoid serious environmental and economic damages from energy use, humans must stop using fossil fuels altogether. One possible strategy to cut the dependence of fossil fuels and, at the same time create a new economic force, is to develop a hydrogen based energy economy. A potentially viable way forward is to produce H2 from water by combining solar energy and heterogeneous photocatalysts. For these reasons the objectives of this investigation were: 1) synthesize high surface area ZnO NWs (nanowires) catalysts with a wurzite crystalline phase; 2) incorporate different amounts of gold nanoparticles (1%, 3%, 5%, 10% wt.), on either the synthetized ZnO catalyst and the commercial form (Alfa Aesar), using a chemical reduction method; and 3) produce hydrogen via water splitting using visible and UV light. The hypotheses of the study were: a) The catalyst with the highest surface area will produce the highest production of hydrogen, and b) The incorporation of graphene on the gold-based catalysts, will enhance the hydrogen production, due to the electronic properties of this material. The incorporation of graphene onto the gold-based catalysts surface enhanced the surface area in both commercial and synthetized form of the catalyst. The hydrogen production obtained by using Au@ZnO commercial-graphene catalysts was measured to be 709 μmolg-1h-1 under irradiation at 400 nm, and 1127 μmolg-1h-1 using Au@ZnO NWs-graphene at the same wavelength. The results showed that the gold-based catalysts are suitable materials for the production of hydrogen via water splitting under visible and ultraviolet light. As future works, different morphology of the catalyst will be synthesized, and other metals such as silver will be incorporated to the as-synthesized catalysts.
Funder Acknowledgement(s): I would like to thank the Department of Energy under the Program Massie Chair of Excellence. Also, I have to say thank you to the University of Madrid for their incredible help and support during this investigation.
Faculty Advisor: Francisco Márquez, fmarquez@suagm.edu
Role: The work that I am submitting is my doctoral research, hence, everything that is reported was conducted by me.