Improved Interfacial Charge Transfer on Noble Metal‐Free Biomimetic CdS‐Based Tertiary Heterostructure @ 2D MoS₂‐CdS‐Cu₂O with Enhanced Photocatalytic Water Splitting

Abstract

High charge separation efficiency with a wide optical absorption window is the prime requirement for the scale up of a stable solar photocatalytic hydrogen generation process. A new noble metal‐free heterostructure of 2D MoS2‐CdS‐Cu2O is designed by depositing cauliflower‐shaped CdS and nanosized Cu2O on exfoliated 2D MoS2. Characterization by XPS, high‐resolution transmission electron microscopy (HRTEM), and UV‐visible spectra confirms the formation of nanosized Cu2O with desired interface formation with MoS2 sheet and CdS thus extending the optical absorption range up to 900 nm. Water splitting activity in the presence of lactic acid is found to be 7.89 and 11.53 mmol g−1 h−1 on MoS2‐CdS and MoS2‐CdS‐Cu2O, respectively, with good repeatability under visible light. Efficient interfacial charge separation is manifested from demised photoluminescence (PL) intensity which supports the suppression of hole‐electron recombination in the tertiary heterostructure. In addition, the formation of dual p‐n junction as indicated from Mott–Schottky analysis further strengthen the faster electron and holes separation objective. Compared to the pure CdS, hydrogen efficiency is 20.96 times higher on a noble metal‐free tertiary catalyst with an apparent quantum efficiency of 8.75%. Hopefully, the 2D material‐based architecture of dual p‐n junction with desired interface engineering will facilitate the catalyst design with increased water splitting activity under solar/visible light.

Sb-Substituted Cs2AgBiBr6/g-C3N4 Composite for Photocatalytic C(sp3)–H Bond Activation in Toluene

“…The different chemical environment of Br in the 20%-CASBB/CN is also reflected by the XPS peak broadening, revealing the increased charge transfer between CASBB and g-C 3 N 4 as a result of heterojunction formation. 69,70 The C 1s peaks at 288.6 and 286.5 eV of 20%-CASBB/CN are at slightly lower binding energy than those of g-C 3 N 4 . A shift of the N 1s peaks to lower binding energies for 20%-CASBB/CN was also observed compared with g-C 3 N 4 .…”

Visible-light driven H2 evolution over a precious metal-free hybrid photocatalyst constructed from CuO and NiFe layered double hydroxide

“…This result suggested the electron donation from Cu to Fe at the interface junction, which was similar to the electron flow from Cd to Mo due to the formation of the CdS–MoS 2 binary composite. 30…”

“…This result suggested the electron donation from Cu to Fe at the interface junction, which was similar to the electron flow from Cd to Mo due to the formation of the CdS-MoS 2 binary composite. 30 The decreases of the near-neighbour coordination shell intensity could be observed for all edges after the hydrothermal compositing reaction (Fig. S4 †).…”

The bandgap of sulfur-doped Ag2O nanoparticles

“…Photocatalysis research demands semiconductor nanostructures with appropriate band structures that ensure charge separation and strong redox driving forces. 4–8…”

“…Photocatalysis research demands semiconductor nanostructures with appropriate band structures that ensure charge separation and strong redox driving forces. [4][5][6][7][8] Introducing defects like vacancies or dopants into the parent semiconductor material can increase charge separation and alter the bandgap and adsorption properties. For instance, Hezam et al synthesized oxygen vacancy (OV) enriched ceria (CeO 2 ) with better charge separation and enhanced photocatalytic activity.…”