Visible-light driven noble metal (Au, Ag) permeated multicomponent Cu2ZnSnS4 nanocrystals: A potential low-cost photocatalyst for textile effluents and heavy metal removal

• Published in: Environmental research 2023-01, Vol.217, p.114875-114875, Article 114875
• Main Authors: Semalti, Pooja, Saroha, Jyoti, Tawale, Jai Shankar, Sharma, Shailesh Narain
• Format: Article
• Language: English
• Subjects: absorption; chromium; copper zinc tin sulfide; cost effectiveness; CZTS; fabrics; heavy metals; Hot-injection; hydrophilicity; light; nanocrystals; nanoparticles; Noble-metals; particle size; Photocatalysis; photocatalysts; photoreduction; remediation; vision; wastewater; Water pollutants
• ISSN: 0013-9351; 1096-0953
• DOI: 10.1016/j.envres.2022.114875

An exemplary vision to understand the fundamental role of metal-doped multi-components system such as Au/Ag doped CZTS (Cu2ZnSnS4) nanocrystals encourages the non-vacuum approach for the best performing photocatalyst. Hydrophilic nanoparticles (Au/Ag and CZTS) are allowed to amalgamate under NTP atmosphere, eradicating the prerequisite for high-end equipment. The potential of Au and Ag-doped CZTS nanoparticles was speculated using various optical and structural characterizations. The absorption range of CZTS nanoparticles lies in the visible range, while Au/Ag doping slightly red-shifts the absorption range, considered the desirable state for photocatalysis. The synthesized nanoparticles are highly monodispersed with ∼15–35 nm particle size for Ag, Au, and CZTS. Photocatalysis is a discernible scheme for treating wastewater containing dyes, textile effluents, chemicals, and heavy metals. Here, we strive to use these ex-situ synthesized nanomaterials as photocatalysts, where the real textile waste (collected from industrial outlets), dyes, and heavy metal (chromium (VI)) have been photo-reduced after scrutinizing the finest combination of Ag or Au doped CZTS. Au-CZTS shows superior catalytic activity with an efficiency of 99.7% with a rate constant of 0.2 min−1 (while Ag-CZTS shows 90% efficiency with a rate constant of 0.07 min−1); hence, used for real textile waste and heavy metal (Chromium VI) photo-reduction. The maximum efficiency achieved for textile-1, textile-2, and Cr (VI) reductions is 80%, 70%, and 97%, respectively. The nanocrystals are highly stable and recyclable, tested for 15 repeated cycles. These studies pave the way for developing cost-effective, environmentally-friendly, durable, and selective semiconductor-metal (Au/Ag) hybrid heterostructures as visible-light-driven photocatalysts for wastewater remediation. [Display omitted] •Colloidal-route ex-situ synthesis of monodispersed Au/Ag–Cu2ZnsnS4 (CZTS) np's reported.•Au/Ag CZTS np's used for photocatalytic degradation of textile & industrial wastes.•Au-CZTS better photocatalyst for textile pollutants, (Eff. ∼99.7%; Rate constant ∼0.2 min−1).•Au-CZTS used for heavy metal Cr reduction (Eff. ∼97%; Rate constant ∼0.007 min−1).•Au/Ag-CZTS photocatalysts are stable, recyclable & tested for 15 consecutive cycles.