TiO2/BiOI p-n junction-decorated carbon fibers as weavable photocatalyst with UV-vis photoresponsive for efficiently degrading various pollutants

Fabricating p-n junctions is an effective strategy to broaden the photoabsorption range and promote electron-hole separation of semiconductor photocatalysts. However, most of the p-n junctions are powder-shaped. Herein, TiO2/BiOI as the model of the p-n junction was applied to be fixed on carbon fiber (CF) to fabricate weavable CF/TiO2/BiOI bundles, which shows strong and broad-spectrum photoabsorption in 200-800 nm. Besides, these bundles were further weaved into cloth (0.1 g, 4 x 4 cm(2)), which exhibits superior adsorption and photodegradation efficiency for various pollutants with visible (Vis) or UV-Vis light irradiation. The obtained CF/TiO2/BiOI cloth can efficiently remove 99.2% methylene blue (MB), 100% rhodamine B (RhB), 100% tetracycline (TC), 97.1% ciprofloxacin (CIP) and 98.9% levofloxacin (LVFX) in 80 min under UV-vis light irradiation, which is higher than that under Vis (91.3% MB, 95.7% RhB, 90.3% TC, 92.7% CIP and 93.8% LVFX) light irradiation. After five cycles, CF/TiO2/BiOI cloth still retains an excellent photocatalytic activity for LVFX degradation (92.1%) under UV-vis irradiation with an easy reusing process. This study provides some insights into the fabrication of reusable macroscopical photocatalysts with high efficiency for environmental purification.

Automated summary

Fabrication of weavable CF/TiO2/BiOI bundles on carbon fiber allows for strong and broad-spectrum photoabsorption, leading to superior adsorption and photodegradation efficiency for various pollutants. The reusable macroscopic photocatalyst retains excellent photocatalytic activity even after multiple cycles, showing potential for environmental purification applications.