As an excellent semiconductor photocatalyst, zinc oxide is widely used in the field of photocatalysis and is regarded as one of the most reliable materials to solve environmental problems. However, because its band gap energy limits the absorption of visible light and reduces the efficiency of catalytic degradation, it needs to be doped with other substances or compounded with other substances and precious metal. This paper summarizes the research on this aspect at home and abroad in recent years, introduces the doping of transition metal ions by zinc oxide, the compounding of zinc oxide with precious metals or other semiconductors, and the prospect of further improving the catalytic efficiency of zno photocatalyst is also put forward.

Titanium dioxide (TiO₂) photocatalysts, characterized by exceptional photocatalytic activity, high photoelectric conversion efficiency, and economic viability, have found widespread application in recent years for azo dye degradation. However, inherent constraints, such as the material’s limited visible light absorption stemming from its bandgap and the swift recombination of charge carriers, have impeded its broader application potential. Encouragingly, these barriers can be mitigated through the modification of TiO₂. In this review, the common synthesis methods of TiO₂ are reviewed, and the research progress of TiO₂ modification technology at home and abroad is discussed in detail, including precious metal deposition, transition metal doping, rare earth metal doping, composite semiconductors, and composite polymers. These modification techniques effectively enhance the absorption capacity of TiO₂ in the visible region and reduce the recombination rate of carriers and electrons, thus significantly improving its photocatalytic performance. Finally, this paper looks forward to the future development direction of TiO₂ photocatalytic materials, including the exploration of new modified materials, in-depth mechanism research, and performance optimization in practical applications, to provide useful references for further research and application of TiO₂ photocatalytic materials.

There are many important cultural relics in China, including many paper relics. Therefore, it is particularly important to find methods of protecting the handwriting in paper relics. This study focuses on the effects acrylic polyurethane materials have on preserving handwriting in paper relics by examining the color change and diffusion of handwriting before and after reinforcement treatments on handwriting materials, including ink, carbon ink, blue-black ink, pure blue ink, red ink, and pencil. The acrylic polyurethane materials have a certain degree of stability and enhance the handwriting of paper relics. We analyzed the acrylic polyurethane reinforcement material in terms of acid resistance, alkali resistance, oxidation resistance, dry heat aging resistance, and durability. The experimental results show that the optimal reinforcement concentration is within 15% for ink, 10% for carbon ink, 20% for blue-black ink, 15% to 20% for pure blue ink, and 3% for red ink and pencil. Finally, the surface of the reinforced paper and handwriting were observed through laser microscopy, SEM, EDS, and infrared spectroscopy and the protective effect of acrylic polyurethane reinforcement material on handwriting was determined.

Perfluorooctanoic acid (PFOA) is a new type of organic pollutant in wastewater that is persistent, toxic, and accumulates in living organisms. The development of rapid and sensitive analytical methods to detect PFOA in environmental media is of great importance. Fluorescence detection has the advantages of high efficiency and low cost, in which fluorescent probes have excellent fluorescence properties, excellent bio-solubility, and remarkable photostability. It is necessary to review the fluorescence detection routes for PFOA. In addition, the up-conversion of fluorescent materials (UCNPs), as fluorescent materials to prepare fluorescent probes with, has significant advantages and also attracts the attention of researchers, however, reviews related to their application in detecting PFOA and comparing them with other routes are rare. Furthermore, there are many strategies to improve the performance of up-conversion fluorescent probes including SiO₂ modification and amino modification. These strategies can enhance the detection effect of PFOA. Thus, this work reviews the types of fluorescence detection, the design, and synthesis of UCNPs, their recognition mechanism, properties, and their application progress. Moreover, the development trend and prospects of these detection probes are given.

Cr is used extensively in industry, so the number of Cr (VI) hazards is increasing. The effective control and removal of Cr (VI) from the environment are becoming an increasing research priority. In order to provide a more comprehensive description of the research progress of chromate adsorption materials, this paper summarizes the articles describing chromate adsorption in the past five years. It summarizes the adsorption principles, adsorbent types, and adsorption effects to provide methods and ideas to solve the chromate pollution problem further. After research, it is found that many adsorbents reduce adsorption when there is too much charge in the water. Besides, to ensure adsorption efficiency, there are problems with the formability of some materials, which impact recycling.