Mediator‐Free S‐Scheme S‐C3N4/Ce2Zr2O7 Heterojunction Hybrid Material for Effective Photocatalytic Degradation of Persistent Organic Pollutants Under Visible Light

Abstract

AbstractIn this study, we demonstrated a Step‐scheme (S‐scheme) based S‐C3N4/Ce2Zr2O7 (SCN/CZ) organic‐inorganic heterostructure, which was synthesized by a facile wet chemical route. The photocatalyst was highly efficient for the remediation of organic pollutants (POPs), namely 2,4‐dichlorophenol (2,4‐DCP, 20 ppm), 4‐chlorophenol (4‐CP, 20 ppm), and phenol (20 ppm) via dehalogenation under visible light (λ≥420 nm). Our finding reveals that a 20 wt.% S‐C3N4 on the surface of the SCN/CZ hybrid is an optimum requirement for potential catalytic activity. We achieve excellent photocatalytic performances i. e., 94 % for 2,4‐DCP, 92 % for 4‐CP, and 90 % for phenol removal, respectively. It was identified that superoxide and hydroxyl radicals (O2⋅− and ⋅OH) are diligently participating in the reaction medium. However, the content of O2⋅− species is more, which we have quantified as ∼66 μM when 20 % SCN/CZ is used. Furthermore, we have established the reaction pathways via an S‐scheme mechanism, which has great importance for photocatalysis. The prepared catalyst is highly stable and reusable for more than five cycles. The work presented here can contribute to the new perspective for pollutant removal via the dehalogenation route over the S‐C3N4/Ce2Zr2O7 surface.