Preparation of enhanced visible light-responsive photocatalytic paper containing Ag/N-TiO₂ aerogel for detoxification of environmental pollutants

Ag/N-TiO2 aerogel photocatalyst (Ag/N-TiO2 ACP) was prepared by the sol-gel method, using AgNO3 and urea as the sources of silver and nitrogen, respectively. The surface of the photocatalyst was modified using an alcoholic solution of ethyl orthosilicate (20% v/v) during the drying process under atmospheric pressure. Ag/N-TiO2 ACP, microcrystalline cellulose (MCC) and polyvinyl butyral (PVB) were combined by electrostatic spinning to prepare Ag/N-TiO2 ACP/MCC composite fibers (Ag/N-TiO2/MCC-CFs). Ag/N-TiO2/MCC-CFs were then composited with pulp fibers to prepare a photocatalytic paper (Ag/N-TiO2/MCC CFs-paper) with a wide spectral response range. Ag/N-TiO2 ACP has a high specific surface area (288.92 m(2)/g) and good antibacterial activity (no obvious colony after 2 h under simulated sunlight). Scanning electron microscopy images showed Ag/N-TiO2/MCC-CFs anchored in the pulp fibers. The composite photocatalytic paper exhibited good antibacterial activity against Escherichia coli (> 97% growth inhibition under simulated sunlight for 2 h) and Staphylococcus aureus (> 91% growth inhibition under simulated sunlight for 2 h). The photocatalytic paper also showed good photocatalytic activity and stability for the degradation of liquid-phase organic pollutants (MB, adsorption-photocatalytic degradation similar to 100%) and volatile organic pollutants (HCHO, adsorption-photocatalytic degradation 57.19%) under light irradiation. This study provides a simple and green method for preparation of a novel paper-based material with effective antibacterial and photocatalytic activity that has potential for photocatalytic sewage purification and degradation of indoor air pollutants, such as HCHO.