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

Abstract

Clean and sustainable energy is an illuminative field of research for scientific community to avoid contagious emissions from burning fossil fuels. Electrocatalytic water splitting holds strong potential to generate clean energy fuel by modern day renewable energy devices. A dual-functional ternary CdS/MoS2/CrS2 heterostructure is designed for electrocatalytic water-splitting properties and photocatalytic dye degradation. The ternary electrocatalyst possesses a low onset potential of 1.47 V and a corresponding overpotential of 248 mV versus RHE in 1 M KOH solution to attain a high current density of 410 mA/cm–2. The Tafel slope value of 37 mV/dec depicts four electron transfers in the electrocatalytic water oxidation process. The optical band gap of the nanostructures is found to be 1.54, 2.13, and 1.55 eV for MoS2, CrS2, and CdS/MoS2/CrS2, respectively, using Tauc plot. Furthermore, photocatalytic degradation of methylene blue (MB) and Congo red (CR) was performed for the ternary photocatalyst as well as pure CrS2. The degradation efficiency of CrS2 and CdS/MoS2/CrS2 was calculated to be 76­(10 ppm) and 90.74­(10 ppm), 90.47%(20 ppm) against MB dye, respectively. In a similar fashion, the photodegradation efficiency of CdS/MoS2/CrS2 heterostructures against the acidic dye, that is, CR, is 90.10­(10 ppm) and 79.13%(20 ppm).

Rapid and Universal Synthesis of 2D Transition Metal (Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W) Sulfides through Oxide Sulfurization in CS2 Vapor

“…In particular, thermodynamic parameters in the case of Mo and W (and “lower” stability of corresponding oxides) allow their preparation using a “simple” hydrothermal approach. A similar gap and oxide stability in the case of Cr also allow utilization of this approach . A limited number of papers were found for Ti, , but some are in contradiction, while others postulate the unsuitability of this simple approach in the case of Ti sulfide .…”

“…A similar gap and oxide stability in the case of Cr also allow utilization of this approach. 35 A limited number of papers were found for Ti, 36 , 37 but some are in contradiction, while others postulate the unsuitability of this simple approach in the case of Ti sulfide. 33 The higher stability of the oxides (compared to sulfides) and related higher energy gap forces lead to the use of the solvothermal approach(es) for preparation of transition metal sulfides.…”