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Aerobic Conditions Enhance the Photocatalytic Stability of CdS/CdO_x Quantum Dots.

ABSTRACT: Photocatalytic H₂ production through water splitting represents an attractive route to generate a renewable fuel. These systems are typically limited to anaerobic conditions due to the inhibiting effects of O₂ . Here, we report that sacrificial H₂ evolution with CdS quantum dots does not necessarily suffer from O₂ inhibition and can even be stabilised under aerobic conditions. The introduction of O₂ prevents a key inactivation pathway of CdS (over-accumulation of metallic Cd and particle agglomeration) and thereby affords particles with higher stability. These findings represent a possibility to exploit the O₂ reduction reaction to inhibit deactivation, rather than catalysis, offering a strategy to stabilise photocatalysts that suffer from similar degradation reactions.

SUBMITTER: Wakerley DW

PROVIDER: S-EPMC6348374 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature

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Aerobic Conditions Enhance the Photocatalytic Stability of CdS/CdOx Quantum Dots.

Wakerley David W DW Ly Khoa H KH Kornienko Nikolay N Orchard Katherine L KL Kuehnel Moritz F MF Reisner Erwin E

Chemistry (Weinheim an der Bergstrasse, Germany) 20180627 69

Photocatalytic H2 production through water splitting represents an attractive route to generate a renewable fuel. These systems are typically limited to anaerobic conditions due to the inhibiting effects of O2 . Here, we report that sacrificial H2 evolution with CdS quantum dots does not necessarily suffer from O2 inhibition and can even be stabilised under aerobic conditions. The introduction of O2 prevents a key inactivation pathway of CdS ...[more]

PMID: 29750379

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