Synthesis of Z-scheme Mn-CdS/MoS₂/TiO₂ ternary photocatalysts for high-efficiency sunlight-driven photocatalysis

Abstract

The exploration of highly efficient visible-light-driven photocatalysts for dye degradation has received great concerns in wastewater treatment. Here, molybdenum disulfide (MoS2) and cadmium sulfide–manganese (CdS-Mn) were sequentially assembled onto titanium dioxide (TiO2) nanotube by a simple hydrothermal method coupled with successive ionic layer adsorption and reaction. A zinc sulfide (ZnS) layer was introduced as a potential barrier for performance improvement; the resultant material exhibits prominent visible-light-induced photocatalytic activity in degrading methyl orange (MO) and 9-anthracenecarboxylic acids, which is 3.16-fold, 2.00-fold, and 1.69-fold or 2.86-fold, 1.56-fold, and 1.47-fold of TiO2, MoS2/TiO2, and CdS-Mn/TiO2 systems, respectively. Furthermore, the synthesized ZnS/CdS-Mn/MoS2/TiO2 composite also possesses a high hydrogen production rate of 408.27 mmol/cm2/h out of water under visible light illumination, which is about 30.08 times greater than that of pure TiO2 and 5.18-fold and 2.52-fold of MoS2/TiO2 and CdS-Mn/TiO2, respectively. The enhanced photocatalyst performances are mainly attributed to the synergetic effects of CdS-Mn, MoS2, and TiO2, forming a Z-scheme system in the CdS-Mn/MoS2/TiO2 electrode, which not only accelerates the interfacial charge transfer efficiency but also preserves the strong redox ability of the photogenerated electrons and holes. In addition, the prepared photoelectrode is highly stable and completely recyclable over hydrogen evolution reaction and organic degradation.

Interface enriched highly interlaced layered MoS2/NiS2 nanocomposites for the photocatalytic degradation of rhodamine B dye

“…Intercalation of NiS 2 in MoS 2 provides grate number of photogenerated electron–hole pairs. 35 Under visible light irradiation, electrons are excited from the valance band of NiS 2 to the conduction band, leaving behind holes in the valence band. The photoinduced electrons in the conduction band of NiS 2 were transferred to the conduction band of MoS 2 , which acted as a photoelectronic receiver.…”

“…It showed good stability towards MO dye under solar light irradiation with the removal rate of 98% in 100 min. 16 Wei Yang Lim et al has studied the interaction of ZnIn 2 S 4 /transition metal chalcogenides for dye degradation. Among them, the ZnIn 2 S 4 /MoS 2 composite exhibits superior MO degradation under visible light irradiation.…”

Application of visible light active photocatalysis for water contaminants: A review

“…Xu et al ( 2020 ) prepared porous polymers/TiO 2 /Cu (PPTC) through a two‐step method and proved it performed better than TiO 2 and TiO 2 /Cu. Feng et al ( 2019 ) synthesized Z‐scheme Mn‐CdS/MoS 2 /TiO 2 ternary photocatalyst, proving it had 3.16 times better performance than TiO 2 alone when treating methyl orange (MO) and 9‐anthracenecarboxylic acids (9‐AC). It degraded N,N ‐dimethylformamide (DMF), MO, MB, and phenol of 73.7%, 97.8%, 100%, and 98.6%, respectively, under 3 h of xenon light exposure.…”

CrS2-Modulated Enhanced Catalytic Properties of CdS/MoS2 Heterostructures Toward Photodegradation and Electrochemical OER Kinetics

“…13 Hui Feng et al synthesized ZnS/CdS−Mn/MoS 2 /TiO 2 heterostructures for their photocatalytic properties and demonstrated their good stability toward the methyl orange dye when exposed to solar light. 14 In a similar way, Archana et al investigated the interaction of CdS and MoS 2 for catalytic applications. Their properties are further enhanced when fabricated through WS 2 as a composite material.…”

“…MoS 2 /CdS nanocomposites have been extensively explored for electrocatalytic oxygen evolution reaction (OER) and photocatalytic degradation of organic dyes . Hui Feng et al synthesized ZnS/CdS–Mn/MoS 2 /TiO 2 heterostructures for their photocatalytic properties and demonstrated their good stability toward the methyl orange dye when exposed to solar light . In a similar way, Archana et al investigated the interaction of CdS and MoS 2 for catalytic applications.…”