Nanosheets of In 2 S 3 /S-C 3 N 4 -Dots for Solar Water-Splitting in Saline Water.

Hydrogen generation from splitting of water under the photoelectrochemical (PEC) pathway is considered as the most promising strategy for covering the upcoming fuel crisis by taking care of all environmental issues. In this context, In 2 S 3 can be explored as it is a visible light-active semiconductor with an appropriate band alignment with the water redox potential. Herein, In 2 S 3 nanosheets are developed by the chemical method. The nanosheets of In 2 S 3 absorb high visible light due to the manifold inside scattering and reflection. The PEC activity of In 2 S 3 is enhanced because of the increase in the light absorbance of the materials. In the present work, at 1.18 V versus RHE in 3.5 wt % NaCl, a maximum 2.07 mA/cm 2 photocurrent density can be achieved by In 2 S 3 nanosheets. However, In 2 S 3 suffers strongly due to photo-corrosion. To improve the efficacy of the In 2 S 3 nanosheets in saline water, the charge-carrier transportation ability of In 2 S 3 is aimed to increase by decorating S-C 3 N 4 -dots on In 2 S 3 . The heterostructure of type-II is developed by sensitization of S-C 3 N 4 -dots on In 2 S 3 . It increases both the transportation of charge carriers as well as separation. In the heterostructure, the transient decay time (τ) increases, which indicates a decrease in photogenerated charge-carrier recombination. S-C 3 N 4 -dots also act as an optical antenna and increase the range of visible light absorbance of In 2 S 3 . The heterostructure can generate ∼2.38-fold higher photocurrent density of 1.18 V versus RHE in 3.5 wt % NaCl. The photoconversion efficiency of the heterostructure is 0.88% at 0.95 V versus RHE. The nanosheets of In 2 S 3 and In 2 S 3 /S-C 3 N 4 -dots are stable, and photocurrent density is measured up to 2700 s under continuous back-illumination conditions.