Abstract
S-scheme photocatalysts are more efficient than the conventional type-II configuration, but the CO2 reduction performances are still unsatisfactory. Herein, we firstly report the layered double hydroxide (LDH) based S-scheme heterostructure photocatalyst (Niln LDH/In2S3) with n-type NiIn LDH and p-type In2S3. The built-in internal electric field directs the photogenerated electrons flow from the conductive band of In2S3 to the valance band of Niln LDH, which is confirmed by operando and theoretical experiments. The CO2 photoreduction intermediates are monitored by in-situ Raman spectra, and the density functional calculations disclose the reduced energy barrier for CO desorption on the heterojunction. Therefore, without cocatalysts or sacrificial agents, the Niln LDH/In2S3 heterojunction delivers a high CO yield rate of 29.43 μmol g~(-1) h~(-1) under visible light irradiation, ecu 3.5 and 4.3 times higher than the single counterpart Niln LDH and In2S3. Notably, this value is the highest among S-scheme CO2 photocatalysts and surpasses most top-ranking benchmarks.
NSTL