花型Bi^0/CeO2-δ等离子体光催化剂增强可见光光催化去除NO

Flower-like Bi^0/CeO2-δ plasmonic photocatalysts with enhanced visible-light-induced photocatalytic activity for NO removal

本文利用溶剂热法合成了Bi^0纳米颗粒修饰的富氧空位(OVs)花型CeO2-δ(Bi^0/CeO2-δ)光催化剂.OVs不仅能够加速电子-空穴对的分离,而且有利于气体分子(NO/O2)的吸附和活化.此外,Bi^0纳米颗粒具有表面等离子体共振效应,它能够提高催化剂的可见光响应、减少光生载流子的复合.Bi^0/CeO2-δ光催化剂在可见光下具有优异的一氧化氮(NO)去除活性,并可有效抑制NO2生成.密度泛函理论(DFT)计算证实,Bi^0与CeO2-δ界面处的肖特基势垒以及OVs的存在促进了载流子的分离,进而参与NO的光催化去除.通过捕获实验和原位红外光谱分析了Bi^0/CeO2-δ催化剂光催化去除NO的机理,研究表明丰富的OVs和金属纳米颗粒负载能够显著提高材料光催化去除NO的性能.

Plasmonic bismuth(Bi^0)nanoparticle-decorated flower-like CeO2-δ(Bi^0/CeO2-δ)photocatalysts with abundant oxygen vacancies(OVs)were synthesized via a solvothermal method.The OVs can not only improve the separation of electron-hole pairs,but also facilitate the adsorption and activation of gas molecules(NO/O2).In addition,the Bi^0 nanoparticles can enhance the visible light response and prevent the recombination of charge carriers by virtue of the surface plasmon resonance(SPR)effect,achieving an excellent ability for NO elimination and NO2 inhibition under visible light irradiation.Density functional theory(DFT)calculations confirm that the Schottky barrier between Bi^0 and CeO2-δaccompanied with the OVs are pivotal for the migration of photogenerated charge carriers to involve in the photocatalytic NO removal.Trapping experiments and in situ FTIR spectroscopy were conducted to explore the mechanism of the photocatalytic NO removal,suggesting that the photocatalytic NO removal can be significantly enhanced by introducing abundant OVs and the involvement of Bi^0 metal nanoparticles.