Photocatalytic paper is a composite photocatalyst generally prepared by loading semiconductors, such as titanium dioxide (TiO$_2$) nanoparticles on paper, and attracts sustaining interests. In this paper, poly-dopamine (PDA) wasloaded on cellulose fibre by in situ oxidative polymerization of dopamine. The PDA-loaded cellulose fibre (PLCF) was used to make TiO$_2$ photocatalytic paper together with pristine cellulose fibre (CF) and TiO$_2$ nanoparticles to improve the performance of the photocatalytic paper. The loading of PDA on CF and the introduction of 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 TiO$_2$ nanoparticles in paper by forming a membranoussubstance. 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 activitywas 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.

TATB (1,3,5-triamino-2,4,6-trinitrobenzene) is a widely used insensitive high-energy explosive. It is significant to study its structural evolution in order to get a credible understand of its properties and performances. Direct mechanical tests such as hardness tests are useful approaches to get information about its mechanical properties and shed light upon the microstructures. However, due to the poor solubility of TATB to most solvents, it is hard to produce large crystals for such tests. Fortunately, microcosmic approaches such as powder diffraction can reinforce it and has low requirement on samples. In this study, series of in-situ neutron diffraction experiments under different pressures areperformed to investigate the structural change and mechanical properties of TATB. The recently reported phase transitionat 4 GPa is studied. The microstrains in normal TATB (12-17 $\mu$m) are analysed to reveal the information of slip system and transitional process. The lattice parameters and bulk moduli of TATB under different conditions are given. These neutron diffraction results are significant supplement to correlative studies and will help to understand the performances of TATB, such as deformation and phase transition.