Single Cobalt Atom Anchored Black Phosphorous Nanosheets as an Effective Cocatalyst Promotes Photocatalysis
© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Exploring novel cocatalysts with sufficient active sites and rapid photogenerated carrier separation remains challenge for boosting photocatalytic reactions. Recently, two-dimensional (2D) black phosphorus (BP) has been developed and recognized to be an ideal platform for anchoring metal ions through lone pair electrons. Herein, we propose a new structure that cobalt atomically dispersed on BP nanosheets (BP−Co), and apply it as cocatalyst for photocatalytic H2 evolution and CO2 reduction under visible light (>420 nm) irradiation. Both scanning transmission electron microscope and X-ray absorption near edge structure verified the existence of phosphorous-coordinated Co sites. The interaction between Co and P brings greatly improvement on photocatalytic activities, and 18-fold enhancement can be achieved on CdS when taking BP−Co as a noble-metal-free cocatalyst for H2 evolution, which is higher than that of Pt under the same conditions. Besides, BP−Co can also be used as an effective cocatalyst to promote photocatalytic CO2 reduction in the presence of photosensitizer [Ru(2, 2’-bipyridy)3]Cl2 with a CO evolution rate of 88.6 μmol h−1, superior to those obtained from the state-of-the-art cocatalysts. It is anticipated that the current work might provide basic understanding as well as new opportunities on 2D BP nanosheets for versatile photocatalytic reactions.