Tuning of interfacial HGO@CLS nanohybrid S-scheme heterojunction with improved carrier separation and photocatalytic activity towards RhB degradation

Sivakumar Vigneshwaran; Do-Gun Kim; Seok-Oh Ko

doi:10.1016/j.chemosphere.2023.139914

Tuning of interfacial HGO@CLS nanohybrid S-scheme heterojunction with improved carrier separation and photocatalytic activity towards RhB degradation

Chemosphere. 2023 Nov:340:139914. doi: 10.1016/j.chemosphere.2023.139914. Epub 2023 Aug 24.

Authors

Sivakumar Vigneshwaran¹, Do-Gun Kim², Seok-Oh Ko³

Affiliations

¹ Environmental System Laboratory, Department of Civil Engineering, Kyung Hee University-Global Campus, 1732 Deogyong-daero, Giheung-Gu, Yongin-Si, Gyeonggi-Do 16705, Republic of Korea.
² Department of Environmental Engineering, Sunchon National University, 255 Jungang-ro, Suncheon, Jellanam-do, 57922, Republic of Korea.
³ Environmental System Laboratory, Department of Civil Engineering, Kyung Hee University-Global Campus, 1732 Deogyong-daero, Giheung-Gu, Yongin-Si, Gyeonggi-Do 16705, Republic of Korea. Electronic address: soko@khu.ac.kr.

PMID: 37633616
DOI: 10.1016/j.chemosphere.2023.139914

Abstract

Herein, we premeditated and invented the innovative hybrid photocatalyst 2D/2D CuLa₂S₄ on holey graphene oxide (HGO) (HGO@CLS) via the hydrothermal method. Electrochemical techniques demonstrate the action of HGO in the HGO@CLS photocatalyst as an effective medium for electron transfer. Combining bimetallic sulfides on porous HGO synergistically provides a higher negative conduction band edge (-0.141 V), greater photo response (10.8 mA/cm²), smaller charge transfer resistance (R_ct = 1.79Ω), and lower photoluminescence (PL) spectral intensity. According to our research, the catalytic recitals are sped up when HGO is assimilated into CLS photocatalyst hetero-junction. Additionally, it lowers the reassimilation rate due to the combined mesh nanostructures and functionality of CLS and HGO. UV-Vis DRS, Mott-Schottky, PL, and Electrochemical impedance spectra (EIS) results manifested that the CuLa₂S₄/HGO makes the spatial separation competent and transference of charge carriers due to the photon irradiation and exhibits superior photocatalytic ability. Electron spin resonance (ESR) analysis confirmed that •OH and h⁺ were the predominant radical species responsible for Rhodamine B(RhB) degradation. Moreover, conceivable degradation ways of RhB were deduced according to the identified intermediates which are responsible for the degradation of recalcitrant products. To check the stability of the photocatalyst, revival tests were also carried out. Similarly, the oxidative byproducts created in the deprivation courses were looked at, and a thorough explanation for the mechanism of degradation was given.

Keywords: Copper lanthanum sulfide; EIS; Holey graphene oxide; Photodegradation; Reusability; RhB.