Research status, challenges and future prospects of renewable synthetic fuel catalysts for CO2 photocatalytic reduction conversion.

In recent years, with global climate change, the utilization of carbon dioxide as a resource has become an important goal of human society to achieve carbon peaking and carbon neutrality. Among them, the catalytic conversion of carbon dioxide to generate renewable fuels has received great attention. As one of these methods, photocatalysis has its unique properties and mechanism, which can only rely on sunlight without inputting other energy. It is an emerging discipline with great development prospects. The core of photocatalysis lies in the development of photocatalysts with high activity, high selectivity, low cost, and high durability. This review first introduces the background and mechanism of photocatalysis, then introduces various types of photocatalysts based on different substrates, and analyzes the methods and mechanisms to improve the activity and selectivity of photocatalysts. Finally, combining the plasmon effect with photocatalysis, the review analyzes the promoting effect of the plasmon effect on the photocatalytic carbon dioxide synthesis of renewable fuels, which provides a new idea for it.

Optimizing the distribution and proportion of various active sites for better NH3-SCR property over Cu/SSZ-13.

The Cu/SSZ-13 catalyst with Si/Al ratio of 10 and Cu/Al ratio in the range of 0.005 to 0.5 was synthesized by ion exchange method. The effect of Cu/Al ratio on the performance, selectivity, and active center of the catalyst SCR was studied. The samples with too low Cu/Al ratio have low catalytic activity in the entire temperature range due to the small number of active sites. The samples with too high Cu/Al ratio have good performance in the low temperature range due to the large number of active sites. However, a large amount of copper that has not undergone ion exchange will generate CuO, which greatly enhances the oxidation of NH3 at high temperatures, which in turn leads to a decrease in catalytic performance at high temperatures. XRD and BET experiments show that all catalyst samples have good CHA crystal structure and microporous structure, and the pore size is mostly about 2 nm. In situ DRIFTS analysis shows that when the Cu/Al ratio is low, the proportion of Z2Cu in the active sites is higher, and the stability of the catalyst is enhanced. When the copper-aluminum ratio is high, the proportion of ZCuOH increases, and the low-temperature activity of the catalyst is higher.

Enhanced biocompatibility and antibacterial property of polyurethane materials modified with citric acid and chitosan.

Citric acid (CA) and chitosan (CS) were covalently immobilized on polyurethane (PU) materials to improve the biocompatibility and antibacterial property. The polyurethane pre-polymer with isocyanate group was synthesized by one pot method, and then grafted with citric acid, followed by blending with polyethersulfone (PES) to prepare the blend membrane by phase-inversion method so that chitosan can be grafted from the membrane via esterification and acylation reactions eventually. The native and modified membranes were characterized by attenuated total reflectance-Fourier transform infrared spectroscope, X-ray photoelectron spectroscopy, scanning electron microscopy, water contact angle measurement, and tensile strength test. Protein adsorption, platelet adhesion, hemolysis assay, activated partial thromboplastin time, prothrombin time, thrombin time, and adsorption of Ca(2+) were executed to evaluate the blood compatibility of the membranes decorated by CA and CS. Particularly, the antibacterial activities on the modified membranes were evaluated based on a vitro antibacterial test. It could be concluded that the modified membrane had good anticoagulant property and antibacterial property.