Harnessing the potential of cube-like Holmium doped bismuth niobate (Ho–Bi5Nb3O15) amalgamated with rGO sheets for rapid photocatalytic elimination of crystal violet and acetylsalicylic acid.

Synthesis of unique morphologies in photocatalytic materials, coupled with utilization of wide-spectrum solar energy through rare earth doping, holds significant promise to maximize the potential of photocatalysts. Herein in, cube-like Holmium (Ho) doped Bi 5 Nb 3 O 15 was synthesized by the hydrothermal method and integrated with reduced graphene oxide (rGO) sheets. As synthesized Ho–Bi 5 Nb 3 O 15 @rGO composite along its analogs i.e., Bi 5 Nb 3 O 15 and Ho–Bi 5 Nb 3 O 15 was characterized by XRD, SEM, FT-IR, TGA, I–V, EIS, Mott-Schottky and photo-current measurements. Phase studies showed that crystallite size for Bi 5 Nb 3 O 15 , Ho–Bi 5 Nb 3 O 15 , and Ho–Bi 5 Nb 3 O 15 @rGO was 27.4, 25.5, and 13.5 nm, respectively. Optical analysis exhibited a reduction in the band gap in consequent to Ho doping from 2.54 to 2.19 eV for Ho–Bi 5 Nb 3 O 15. Conductivity and photo-current measurements showed a remarkable increase in both electrical conductivity and photo-response of Ho–Bi 5 Nb 3 O 15 upon its incorporation into rGO matrix, reaching maximum values of 1.72 × 10−2 S/m and 0.66 μA, respectively. The enhanced photocatalytic activity of Ho–Bi 5 Nb 3 O 15 @rGO was ensured through the outstanding photo-degradation efficiency (96.5 %) against crystal violet (CV), greater than Bi 5 Nb 3 O 15 (49 %) and Ho–Bi 5 Nb 3 O 15 (63.4 %). Additionally, Ho–Bi 5 Nb 3 O 15 @rGO showed sufficient potential towards the degradation of acetylsalicylic acid (ASA) with 79.1 % photo-degradation. This elevated photocatalytic activity of Ho–Bi 5 Nb 3 O 15 @rGO is believed to be contributed by the collaborative outcomes aroused from the Ho-doping and heterojunction fabrication among cubical Ho–Bi 5 Nb 3 O 15 and rGO sheets. Hence, our work proposes an efficient strategy for the development of innovative photolytic materials for sustainable wastewater remediation. [ABSTRACT FROM AUTHOR]