Hongwei He,Zhoulin Ma,Shuya Zhang,An Cai,Huan Ye,Xiaobin Fan,Wenchao Peng,Yang Li
A palladium–zinc alloy nanoparticles decorated nitrogen-doped porous carbon catalyst (PdZn 30 –NC) was synthesized and utilized for Suzuki coupling reaction. The alloying palladium (Pd) with zinc (Zn) and pore expanding are realized simultaneously. Density functional theory (DFT) calculations and experimental studies reveal that the alloying Pd with Zn can lower the energy barrier in Suzuki coupling reaction. Nitrogen adsorption–desorption measurements uncover that pore expansion caused by the zinc nitrate hexahydrate assisted calcination gives rise to the multiplication of mesopore with a pore diameter of 6 nm, which facilitates mass transfer during the reaction. As a result, the alloying Pd with Zn and pore expanding together endow PdZn 30 –NC with excellent catalytic activity. PdZn 30 –NC demonstrates exceptional catalytic activity and stability in Suzuki coupling reaction. A high biphenyl yield of 97.7 % within 40 min and stable reusability of 93.3 % yield after five reuse cycles can be achieved. This work not only offers a viable method for Suzuki coupling reaction, but also provides insights for designing new catalysts toward Suzuki coupling reaction.
Superhydrophilic oil-water separation membranes exhibit fixed interfacial properties, which limits their ability to withstand oil fouling. Enhancing the in-situ anti-fouling performance of membranes dynamically at the interface is challenging. Here, a structurally adjustable pH-responsive membrane for oil-water separation was prepared, combined with patterned silver gel to impart conductivity. Acting as a cathode, this membrane electrolyzes water to generate OH − ions that directly regulate the interfacial pH. The generated OH − ions trigger the responsive layers' contraction, which results in the expansion of the membrane's pore size. Such structural adjustments could shorten the oil-water-solid three-phase contact line of pinned oil droplets to reduce the adhension force, creating interfacial disturbances that enhance the anti-fouling capabilities of membrane. By this way, lubricants and crude oils adhered to the membrane could be de-wetted in 32 s without other assistance. Meanwhile, the expansion of the membrane's pore size increases the washing efficiency. The flux recovery rate after 300 min long-term cycling can reach up to 97.6 % without additional reagents. The fabricated anti-fouling membrane significantly improves separation efficiency and holds great potential for applications in oily wastewater treatment.
危险品化学品经营许可证（带存储）