中文摘要：

纳米金催化剂由于具有条件温和、专一性强等特点而广泛用于多相绿色催化过程中,但它易团聚、难分离、难回收的特点使其应用受到限制。受到聚多巴胺（PDA）具有黏附性和还原性的启发,本文利用PDA原位还原四氯金酸制备了一种多层负载型SiO_2@PDA@Au催化剂颗粒。PDA可以紧密且连续地包覆在SiO_2表面,并可实现金纳米颗粒的原位还原和负载;金含量随着PDA层厚的增加而增加,金颗粒粒径较均一、无团聚,粒径约为30nm;当Au负载量（质量分数）为1.59%时,对亚甲基蓝（MB）的还原反应的催化活性最好（表观反应速率常数Kapp=1.613 4min-1）,且具有良好的循环稳定性。

英文摘要：

Due to the mild working condition and good selectivity as a catalyst, gold nanoparticles （AuNPs） have attracted increasing attention and were widely used in multi-phase green catalytic process. However, AuNPs in solution are unstable, susceptible to aggregation,and difficult in recovery which limits their applications. Inspired by the universal adhesive ability and redox activity of polydopamine（PDA） , the catalytic particle（Si02 @PDA@Au） ,composed of a silica core particle,a PDA interlayer coated on the core, and the inrsitu reduced AuNPs deposited on the PDA layer,was designed and prepared. PDA can be coated on Si02 surface tightly and continuously,and the inrsitu reduction and loading of AuNPs can be efficiently achieved. The amount of AuNPs increases upon increasing the thickness of PDA. The obtained AuNPs are around 30 nm in diameter with narrow size distribution and without aggregation. The Si02@PDA@Au hybrid catalysts with 1. 59% of AuNPs loaded exhibit good catalytic performance （Kapp = 1 . 613 4 min-1） with excellent recycling stability for the reduction reaction of methylene blue（MB）.