Structurally Modulated NiV-LDH with CdMoSe-Quantum Dots: Unlocking the Active Centers at S-Scheme Heterojunctions for Stimulating Photocatalytic H<sub>2</sub>O<sub>2</sub> Production and H<sub>2</sub> Evolution
Preeti Prabha Sarangi, Kundan Kumar Das, Jyotirmayee Sahu, Upali Aparajita Mohanty, Dipti Prava Sahoo, Kulamani Parida
Abstract
High Resolution Image Download MS PowerPoint Slide Designing and accumulating quantum dots (QD) onto layered double hydroxide (LDH) for the photocatalytic production of H 2 and H 2 O 2 is a formidable task. Here, we intended the synthesis procedure of CdMoSe-QD (CMS)-incorporated NiV-LDH (NV) through a facile in situ reflux method and explored the photocatalytic activities of the CMS/NV (CNV) heterostructure. CNV-1 exhibits a large interface contact area and assures excellent interfacial charge transfer ability. Moreover, CNV-1 exhibits outstanding H 2 and H 2 O 2 production rates, i.e., 6.4 and 2.5 times higher than that of pristine NV, respectively, due to formation of an S-scheme heterojunction between NV and CMS. Both NV and CMS function as n-type semiconductors and extend photoresponse to visible regions. The CNV-1 composite achieves 1.67% SCC for photocatalytic H 2 O 2 generation and 7.36% ACE for photocatalytic H 2 evolution. The excellent activity is ascribed to higher anodic photocurrent, the quantum confinement effect of CMS, large surface-active sites, and delayed recombination of excitons as supported by PL and EIS measurements. Further, the S-scheme mechanism was authenticated through a radical scavenging test and work function, evaluated by UPS measurement. Altogether, this study exemplifies the concepts of designing a CNV heterostructure, which operates via an n–n-based S-scheme mechanism and aims to enhance photocatalytic H 2 and H 2 O 2 production.