Improved photocatalytic degradation of rhodamine B by g-C3N4 loaded BiVO4 nanocomposites

Priti Rohilla; Bonamali Pal; Raj Kumar Das

doi:10.1016/j.heliyon.2023.e21900

Improved photocatalytic degradation of rhodamine B by g-C₃N₄ loaded BiVO₄ nanocomposites

Heliyon. 2023 Nov 5;9(11):e21900. doi: 10.1016/j.heliyon.2023.e21900. eCollection 2023 Nov.

Authors

Priti Rohilla¹, Bonamali Pal^{1

2}, Raj Kumar Das^{1

2}

Affiliations

¹ School of Chemistry and Biochemistry, Thapar Institute of Engineering & Technology, Patiala, 147004, Punjab, India.
² TIET-Virginia Tech Center of Excellence in Emerging Materials, Thapar Institute of Engineering and Technology, Patiala, 147004, India.

Abstract

Photocatalytic degradation has emerged as one of the most efficient methods to eliminate toxic dyes from wastewater. In this context, graphitic nitride (g-C₃N₄) loaded BiVO₄ nanocomposites (5 wt% g-CN@BiVO₄ and 10 wt% g-CN@BiVO₄) have been fabricated by the wet impregnation method, and their efficiency towards photocatalytic removal of rhodamine B have been investigated under visible light irradiation. These hybrid composites have been characterized by XRD, FESEM, HRTEM, EDS-mapping, UV-Vis DRS, DLS, XPS and BET, etc. The HRTEM images revealed that BiVO₄ has a decagonal shape covered by a layered nanosheet-like structure of g-C₃N₄. BET measurements suggest increasing the proportion of g-C₃N₄ results enhancement of the specific surface area. Among different photocatalysts, the 10 wt% g-C₃N₄@BiVO₄ hybrid possesses the best catalytic activity with 86% degradation efficiency after 60 min of reaction time. The LC-MS studies suggest that the degradation reactions follow the de-ethylation pathway. Even after five cycles, the heterostructure shows only a 14% decrease in photocatalytic activity, confirming its stability. As a result, the binary composite can be regarded as a promising catalyst for the degradation of pollutants due to its ease of preparation, high stability and superior catalytic activity.

Keywords: BiVO4; Binary composite; Emerging contaminants; Photocatalysis; Wastewater treatment.