Control of monomeric Vo’s versus Vo clusters in ZrO2−x for solar-light H2 production from H2O at high-yield (millimoles gr−1 h−1)
Yiannis Deligiannakis, Asterios Mantzanis, Areti Zindrou, Szymon Smykała, Maria Solakidou
Abstract
Abstract Pristine zirconia, ZrO 2 , possesses high premise as photocatalyst due to its conduction band energy edge. However, its high energy-gap is prohibitive for photoactivation by solar-light. Currently, it is unclear how solar-active zirconia can be designed to meet the requirements for high photocatalytic performance. Moreover, transferring this design to an industrial-scale process is a forward-looking route. Herein, we have developed a novel Flame Spray Pyrolysis process for generating solar-light active nano-ZrO 2−x via engineering of lattice vacancies, Vo. Using solar photons, our optimal nano-ZrO 2−x can achieve milestone H 2 -production yield, > 2400 μmolg −1 h −1 (closest thus, so far, to high photocatalytic water splitting performance benchmarks). Visible light can be also exploited by nano-ZrO 2−x at a high yield via a two-photon process. Control of monomeric Vo versus clusters of Vo’s is the key parameter toward Highly-Performing-Photocatalytic ZrO 2−x . Thus, the reusable and sustainable ZrO 2−x catalyst achieves so far unattainable solar activated photocatalysis, under large scale production.