Preparing photocatalytic paper with improved catalytic activity by in situ loading poly-dopamine on cellulose fibre

Abstract

Photocatalytic paper is a composite photocatalyst generally prepared by loading semiconductors, such as titanium dioxide ($\text {TiO}_{2})$ nanoparticles on paper, and attracts sustaining interests. In this paper, poly-dopamine (PDA) was loaded on cellulose fibre by in situ oxidative polymerization of dopamine. The PDA-loaded cellulose fibre (PLCF) was used to make $\text {TiO}_{2}$ photocatalytic paper together with pristine cellulose fibre (CF) and $\text {TiO}_{2}$ nanoparticles to improve the performance of the photocatalytic paper. The loading of PDA on CF and the introduction of $\text {TiO}_{2}$ nanoparticles in paper were verified by infrared spectroscopy and X-ray diffraction technique, respectively. As observed by scanning electron microscopy, the introduction of PLCF significantly improved the distribution of $\text {TiO}_{2}$ nanoparticles in paper by forming a membranous substance. The photocatalytic performance of the as-prepared photocatalytic paper was analysed by decomposing methyl orange under UV light irradiation. It was confirmed that the occurrence of PLCF significantly improved the photocatalytic performance of the photocatalytic paper. The paper with the highest photocatalytic activity was prepared using a PLCF-to-CF mass ratio of 1:1. The photocatalytic paper with PLCF is stable in the process of repeated application. This work provided a new approach to prepare photocatalytic paper with improved photocatalytic activity.