In this study, a N₂-assisted thermal treatment method is proposed for in-situ formation of a series of oxygen vacancies (OVs)-rich Bi⁰/Bi-based photocatalysts, including OVs-(BiO)₂CO₃, Bi⁰/OVs-(BiO)₂CO₃, Bi⁰/OVs-(BiO)₂CO₃/β-Bi₂O₃, Bi⁰/OVs-β-Bi₂O₃, Bi⁰/OVs-β-Bi₂O₃/α-Bi₂O₃ and Bi⁰/α-Bi₂O₃. Mechanisms of in-situ formation of Bi⁰ nanoparticles and generation of OVs in Bi-based photocatalysts are clarified. Apart from their contribution to the effective separation of photogenerated charge carriers and enhancement of light absorption, the effects of Bi⁰ nanoparticles and OVs on selective photocatalytic oxidation of NO are also investigated. Among the synthesized Bi-based photocatalysts, Bi⁰/OVs-(BiO)₂CO₃ shows the best photocatalytic activity and stability for photo-oxidative removal of NO. The systematic study of photocatalytic mechanism demonstrated that the Ohmic contact between OVs-(BiO)₂CO₃ and Bi⁰ gradually promote the formation of •O₂^– and •OH species. It is found that •O₂^– plays an important role in the photocatalytic NO removal process, while •OH species can effectively inhibit the formation of NO₂ during the NO removal process. The new approach demonstrated in this study can be applied for the in-situ formation of wide-solar-spectrum-responsive photocatalysts with efficient photocatalytic activity.

在这项研究中，提出了一种N ₂辅助热处理方法，用于原位形成一系列富氧空位（OVs）的Bi ⁰ / Bi基光催化剂，包括OVs-（BiO）₂ CO ₃，Bi ⁰ / OVs-（BIO）₂ CO ₃，铋⁰ / OVs-（BIO）₂ CO ₃ /β-Bi系₂ ö ₃，铋⁰ / OVS-β-Bi系₂ ö ₃，铋⁰ / OVS-β-Bi系₂ ø ₃ /α-Bi系₂ ö ₃和Bi ⁰/α-Bi系₂ ö ₃。阐明了Bi ⁰纳米粒子的原位形成机理和OVs的生成机理。除了有助于有效分离光生电荷载流子和增强光吸收外，还研究了Bi ⁰纳米颗粒和OVs对NO选择性光催化氧化的影响。在合成的Bi基光催化剂中，Bi ⁰ / OVs-（BiO）₂ CO ₃表现出最好的光催化活性和对NO进行光氧化去除的稳定性。对光催化机理的系统研究表明，OVs-（BiO）₂之间的欧姆接触CO ₃和Bi ⁰逐步推进•的O形成₂ ^-物种和•OH。发现•O ₂ ^–在光催化脱硝过程中起着重要作用，而•OH物种可以在脱NO过程中有效抑制NO ₂的形成。在这项研究中证明的新方法可以用于具有有效的光催化活性的宽太阳光谱响应光催化剂的原位形成。