羟基磷灰石纳米棒的可控制备及其催化一氧化碳氧化性能

采用简单的一步水热法,以赖氨酸为沉淀剂,通过改变赖氨酸浓度,合成不同尺寸的羟基磷灰石(HAP)纳米棒,负载质量分数3%Ag制备Ag/HAP催化剂。利用Ag与HAP之间的强相互作用将Ag纳米粒子分散在HAP载体表面,使其具有较好的催化活性。活性测试发现,赖氨酸浓度为0. 20 mol·L~(-1)时,制备的Ag/HAP催化剂催化性能最好,在空速为60 000 mL·(g·h)~(-1)条件下,CO的完全转化温度为190℃。XRD和SEM表征结果表明,赖氨酸浓度对Ag/HAP催化剂的结构和性能影响较大。UV-vis、H_2-TPR和XPS测试结果表明,活性组分Ag主要以Ag~0和Ag~+的形式存在于HAP载体上,其中Ag0作为主要催化活性中心,使Ag/HAP催化剂在CO氧化反应中保持较高的活性。

Controllable preparation and catalytic activity for CO oxidation of hydroxyapatite nanorods

A simple one-step hydrothermal method was used to prepare Ag/HAP catalyst with Ag mass fraction of 3% by changing lysine concentration and synthesizing hydroxyapatite (HAP) nanords of different sizes as the support.The strong interaction between Ag and HAP was used to anchor Ag nanoparticles on HAP surface,so as to achieve better catalytic activity.Ag/HAP catalyst prepared with lysine concentration of 0.20 mol·L^-1 was the best,and the 100% conversion of CO was achieved at 190 ℃ with space velocity of 60 000 mL·(g·h)^-1.The XRD and SEM results showed that lysine concentration had a significant effect on the structure and performance of Ag/HAP catalyst.UV-vis,H₂-TPR and XPS tests showed that Ag was mainly in the form of Ag⁰ and Ag⁺ on HAP support,and Ag⁰as the main catalytic activity center.Thus,the Ag/HAP catalyst maintained high activity in CO oxidation reaction.