Photocatalysts that store the sun’s energy in chemical bonds are needed to combat global warming and reduce humanity’s reliance on fossil fuels. Our DMREF project involves the design of hybrid nanostructured photo-catalysts comprising semiconductor quantum dots (QDs) interfaced with metal-intercalated vanadium oxides and related materials. Individual materials components each mediate a subset of the overall sequence of fuel-forming chemical reactions involved in solar photocatalysis.

Our DMREF team recently reported two major results. First, we developed a new photocatalytic architecture by interfacing QDs with Sb2VO5, a semiconductor with a high density of midgap lone pair-derived electronic states that enable barrier-free, ultrafast extraction of holes from photoexcited QDs. Sb2VO5/QD heterostructures photo-catalyze reduction and oxidation half-reactions integral to fuel-forming chemistry. Second, we achieved molecular-level control over excited-state charge-transfer dynamics and photocatalytic mechanisms within molecularly-tethered QD/MoS2 heterostructures that evolve hydrogen from water in the absence of a solvated co-catalyst.