Tin sulfide nanoparticles as photocatalysts for the degradation of organic dyes

Abstract

Tin sulfide (SnS) nanoparticles were prepared from tin(II) dithiocarbamate single source precursors. Powder X-ray diffraction patterns of the SnS nanoparticles confirmed orthorhombic herzenbergite phase of tin sulfide. High-resolution transmission electron microscope images show spherically shaped tin sulfide with particles size in the range 1.0–2.8 nm. The bandgap energy obtained from Tauc plots is in the range 2.95–3.32 eV. The as-prepared SnS nanoparticles were used as nano photocatalysts for the degradation of brilliant green (BG), crystal violet (CV), methylene blue (MB) and methyl red (MR) under visible light irradiation. The degradation efficiency of BG by the SnS nanoparticles after 180 min irradiation are 76%, 81% and 70% by SnS-1, SnS-2 and SnS-3. Degradation efficiency of 66%, 90% and 75% were obtained for SnS-1, SnS-2 and SnS-3, respectively, against CV dye. While the efficiency of 79%, 97% and 93% were obtained for SnS-1, SnS-2 and SnS-3, respectively, against MB dye. The results showed that the as-prepared SnS nanoparticles are efficient photocatalyst for the degradation of BG, CV, MB and MR dyes. Liquid chromatography-mass spectrometry was used to investigate the degradation pathway of the organic dyes. The effects of irradiation time, scavengers and photostability on the photocatalysis process were also evaluated.

GRAPHICAL ABSTRACT

KEYWORDS:

• SnS nanoparticles
• organic dyes
• photodegradation
• scavenging activity
• degradation pathway

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

National Research Foundation [grant number 129275] and University of KwaZulu-Natal are duly appreciated by the authors for research funding.