No abstract

High photoinduced charge-carrier-separation efficiency plays a crucial factor in determining the photocatalytic activities of photocatalysts, and it remains challenging to steer the charge separation in an accurate manner. Herein, we address this important challenge by growing the Co2P cocatalyst onto the edges of black phosphorus (BP) nanosheets to craft Co–P bonds in the Co2P/BP nanosheets photocatalyst. As demonstrated by the photocurrent measurement and first-principle calculation, the Co–P bonds acting to faciliate atomic-level charge-flow steering can improve the photogenerated charge-carrier transfer between BP nanosheets and the Co2P cocatalyst, resulting in the improved photocatalytic performance of the Co2P/BP photocatalyst for H2 generation. As expected, the photocatalytic H2 generation rate of the Co2P/BP nanosheets photocatalyst is 39.7 times greater than that of bare BP nanosheets. Moreover, the Co2P grown on the edges of BP nanosheets inhibits the degradation of the BP nanosheets, resulting in its good stability for photocatalytic H2 production.

No abstract

Two obstacles hindering solar energy conversion by photoelectrochemical (PEC) water-splitting devices are the charge separation and the transport efficiency at the photoanode-electrolyte interface region. Herein, core-shell-structured Ni@Ni(OH) nanoparticles were electrodeposited on the surface of an n-type Si photoanode. The Schottky barrier between Ni and Si is sensitive to the thickness of the Ni(OH) shell. The photovoltage output of the photoanode increases with increasing thickness of the Ni(OH) shell, and is influenced by interactions between Ni and Ni(OH) , the electrolyte screening effect, and the p-type nature of the Ni(OH) layer. Ni@Ni(OH) core-shell nanoparticles with appropriate shell thicknesses coupled to n-type Si photoanodes promote the separation of photogenerated carriers and improve the charge-injection efficiency to nearly 100 %. An onset potential of 1.03 V versus reversible hydrogen electrode (RHE) and a saturated current density of 36.4 mA cm was obtained for the assembly.