Three different cathodic materials for the hydrogen evolution reaction (HER) consisting of Ru nanoparticles (NPs) supported onto a bare and two doped reduced graphene oxides (r-GO) have been studied. Ru NPs have been synthesized in situ by means of the organometallic approach in the presence of each reduced graphene support (bare (rGO), N-doped (NH-rGO) and P-doped (P-rGO)). (HR)TEM, EDX, EA, ICP-OES, XPS, Raman and NMR techniques have been used to fully characterize the obtained rGO-supported Ru materials.
View Article and Find Full Text PDFFeNi oxides/hydroxides are the best performing catalysts for oxidizing water at basic pH. Consequently, their improvement is the cornerstone to develop more efficient artificial photosynthetic systems. During the last 5 years different reports have demonstrated an enhancement of their activity by engineering their structures via: (1) modulation of the number of oxygen, iron and nickel vacancies; (2) single atoms (SAs) doping with metals such as Au, Ir, Ru and Pt; and (3) modification of their surface using organic ligands.
View Article and Find Full Text PDFWater oxidation to dioxygen is one of the key reactions that need to be mastered for the design of practical devices based on water splitting with sunlight. In this context, water oxidation catalysts based on first-row transition metal complexes are highly desirable due to their low cost and their synthetic versatility and tunability through rational ligand design. A new family of dianionic bpy-amidate ligands of general formula H LN (LN is [2,2'-bipyridine]-6,6'-dicarboxamide) substituted with phenyl or naphthyl redox non-innocent moieties is described.
View Article and Find Full Text PDFBoth global warming and limited fossil resources make the transition from fossil to solar fuels an urgent matter. In this regard, the splitting of water activated by sunlight is a sustainable and carbon-free new energy conversion scheme able to produce efficient technological devices. The availability of appropriate catalysts is essential for the proper kinetics of the two key processes involved, namely, the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER).
View Article and Find Full Text PDFIn this work we lay out design guidelines for catalytically more efficient organic photocathodes achieving stable hydrogen production in neutral pH. We propose an organic photocathode architecture employing a NiO hole selective layer, a PCDTBT:PCBM bulk heterojunction, a compact TiO2 electron selective contact and a RuO2 nanoparticle catalyst. The role of each layer is discussed in terms of durability and function.
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