Hydrated electrons mediated in-situ construction of cubic phase CdS/Cd thin layer on a millimeter-scale support for photocatalytic hydrogen evolution

摘要

In this study, non-noble metal Cd decorated cubic phase CdS (CdS/Cd) thin layer on a millimeter-scale chitosan-Mg(OH)(2) xerogel beads (CMB) were elaborately designed and successfully synthesized via facile hydrated electrons (e(aq)(center dot)) assistant strategy. The in-situ formation of metallic Cd was driven by e(aq)(center dot) generated from UV/Na2SO3 process. Owing to metallic Cd, CMB@CdS/Cd exhibited better visible-light absorption ability and more efficient separation capability for photo-induced carriers, its hydrogen production efficiency was about threefold improved compared to CMB@CdS. Both characterization methods and density functional theory calculations determined a built-in electric field from metallic Cd to CdS and Ohmic-contact between Cd and CdS, which largely promoted the carriers transfer efficiency. Moreover, the introduction of metallic Cd on the CdS could reduce the Delta G(H*), thus greatly boosting the photocatalytic hydrogen production efficiency. This work provides a simple and green approach to construct metallic Cd coupled semiconductor to achieve efficient photocatalytic applications. (C) 2021 Elsevier Inc. All rights reserved.