铜纳米颗粒修饰多孔氮化硼高效还原对硝基苯酚的研究

Reduction of p-nitrophenol by copper nanoparticles modified porous boron nitride

为了寻找高催化活性、环境友好、价格低廉、稳定性好的催化剂,研究金属与载体之间的协同催化效应,采用煅烧前驱体法制备了表面富含羟基和氨基的高比表面积多孔h-BN载体,通过简单的液相还原法成功地制备出粒径分布均匀的Cu/h-BN纳米复合材料,并对复合材料的组成、微观结构和性能进行表征。结果显示,铜纳米粒子的引入并未破坏多孔h-BN的二维片状结构,但比表面积及孔径均有不同程度的下降。以对硝基苯酚(4-NP)还原为对氨基苯酚(4-AP)为模型反应,考察Cu/h-BN复合材料的催化性能,当Cu含量为6%(质量分数)时,复合纳米材料具有最高的催化性能(表观反应速率常数k=4.62×10^(-2) s^(-1))和稳定性,催化活性在5个循环内基本保持不变。因此,具有高比表面积的h-BN载体负载可稳定Cu纳米颗粒,它们之间的协同催化作用使Cu/h-BN具有优异的催化活性和稳定性。此研究为今后进一步研究金属与h-BN协同催化提供了理论基础。

In order to search for catalysts with high catalytic activity,environmental friendliness,low price,and good stability,and to investigate the synergistic catalytic effect between metals and supports,porous h-BN carriers with a large specific surface area,meanwhile rich in hydroxyl and amino groups on the surface,were prepared by the calcined precursor method.Cu/BN nanocomposites with uniform particle size distribution were successfully prepared by a simple liquid phase reduction method.The composition,microstructure and properties of the composites were characterized.The results show that the introduction of Cu NPs does not destroy the two-dimensional sheets structure of porous h-BN,but the specific surface area and pore size decrease to varying degrees.Through investigating the catalytic performance of Cu/h-BN composite materials by using the reduction of p-nitrophenol(4-NP) to p-aminophenol(4-AP) as a model reaction,it shows that when the Cu NPs content is 6%(mass fraction),the Cu/h-BN composite material exhibits the best catalytic activity(the reaction rate constant k= 4.62×10^(-2) s^(-1)) and stability,and the catalytic activity remains unchanged in five cycles.Therefore,the h-BN carrier with a high specific surface area can stabilize Cu nanoparticles,and the synergistic catalytic effect between them enables Cu/h-BN to have excellent catalytic activity and stability.The study provides a theoretical basis for further research on the synergistic catalysis of metals and h-BN in the future.