A simple, low cost, non-toxic and eco-friendly pathway for synthesizing efficient sunlight-driven tin sulfide photocatalyst was studied. SnS nanocrystals were prepared by using mechanical method. The bulk SnS was obtained by evaporation of SnS nanocrystal solution. The synthesized samples were characterized by using XRD, SEM, TEM, UV-vis, and Raman analyses. Well crystallized SnS nanocrystals were verified and the electrochemical characterization was also performed under visible light irradiation. The SnS nanocrystals have shown remarkable photocurrent density of 7.6 mA cm−2 under 100 mW cm−2 which is about 10 times larger than that of the bulk SnS under notably stable operation conditions. Furthermore, the SnS nanocrystals presented higher stability than the bulk form. The IPCE(Incident photon to current conversion efficiency) of 9.3% at 420 nm was obtained for SnS nanocrystal photoanode which is strikingly higher than that of bulk SnS, 0.78%. This work suggests that the enhancement of reacting area by using SnS nanocrystal absorbers could give rise to the improvement of photoelectrochemical cell efficiency.

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Cost-effective, abundant, and non-toxic SnS nanosheet semiconductors can be used as water-splitting cells. Herein, a photoanode based on high-purity and highly crystalline SnS nanosheets was fabricated. We used sodium thiosulfate (Na2S2O3·5H2O) and stannous chloride (SnCl2·2H2O) as the tin and sulfur source materials, in place of SnCl4 and H2S gas, respectively, which have been used in previous studies. This gas-free fabrication process represents a new, environment-friendly fabrication method that can reduce the manufacturing cost of SnS nanosheets. The fabricated samples were characterized via X-ray diffraction, ultraviolet-visible spectroscopy, XPS, scanning electron microscopy, and Raman analyses. The XPS result indicated no Sn0 or Sn4+ in the S3 nanosheet; the nanosheet was SnS. These results with XRD show that the SnS nanosheet has high phase purity and crystallinity. Its direct optical band gap is 1.31 eV, and its lattice parameters are similar to those of standard SnS. The SnS nanosheet-based photoanode exhibited a maximum saturation photocurrent of 6.86 mA cm−2 at 0.57 V versus Ag/AgCl, with high stability. The most effective photocurrent for the photocatalytic water-splitting cell is attained with an increase in the surface area and developed electrical conduction. This is attributed to thermal annealing, which eliminates nanoparticle imperfections. This study confirms that SnS nanosheets are excellent candidates for water-splitting applications.