Investigations on the surface modification of ZnO nanoparticle photocatalyst by depositing Pd
Investigations on the surface modification of ZnO nanoparticle photocatalyst by depositing Pd
复制标题
DOI：
10.1016/j.jssc.2004.08.016
复制
发表时间：
2004-11
影响因子：
3.3
通讯作者：
J. Liqiang;Wang Bai-qi;Xin Bai-fu;Li Shudan;Shi Ke-ying;C. Weimin;Fu Honggang
中科院分区：
文献类型：
--
作者：
J. Liqiang;Wang Bai-qi;Xin Bai-fu;Li Shudan;Shi Ke-ying;C. Weimin;Fu Honggang
本文采用光还原法在ZnO纳米粒子表面沉积Pd对ZnO纳米粒子光催化剂进行改性。利用XPS和SPS（Surface Photovoltage Spectroscopy）研究了Pd对ZnO纳米粒子的改性机理以及对ZnO纳米粒子光催化活性的影响，并从电子能级的角度讨论了Pd含量对SPS响应的影响。结果表明，沉积适量Pd后，ZnO纳米粒子表面晶格氧含量减少，吸附氧含量增加，表明Pd主要沉积在晶格氧上。同时，ZnO纳米粒子的SPS响应强度显著降低。此外，在ZnO纳米粒子上沉积适量的Pd，可以显著提高ZnO纳米粒子在气相光催化氧化n-C7 H16中的活性。可见，表面吸附氧含量的增加有利于光催化反应的进行，且光催化活性与SPS响应之间存在密切关系，即SPS响应越弱，光催化活性越高。
In this paper, ZnO nanoparticle photocatalysts were modified by depositing Pd on their surfaces with a photoreduction method. We mainly investigated the modification mechanisms as well as the effects on the photocatalytic activity of ZnO nanoparticles of deposited Pd by means of XPS and SPS (Surface Photovoltage Spectroscopy), and the effects of Pd content on SPS responses were also discussed from the point of the electronic energy level. The results showed that the content of crystal lattice oxygen on the surface of ZnO nanoparticle decreased after an appropriate amount of Pd was deposited, while that of adsorbed oxygen increased, indicating that Pd was mainly deposited on the crystal lattice oxygen. At the same time, the intensity of SPS responses of ZnO nanoparticles remarkably decreased. In addition, the activity of ZnO nanoparticles could be greatly improved by depositing an appropriate amount of Pd in the gas phase photocatalytic oxidation of n-C7H16. Thus, it could be concluded that the increase in surface content of adsorbed oxygen could facilitate the photocatalytic reaction, and there were close relationships between the SPS response and photocatalytic activity, i.e. the weaker the SPS response, the higher the photocatalytic activity, of Pd-deposited ZnO nanoparticles.