Feng Yibo, Wang Cong, Cui Peixin, Li Chong, Zhang Bin, Gan Liyong, Zhang Shengbai, Zhang Xiaoxian, Zhou Xiaoyuan, Sun Zhiming, Wang Kaiwen, Duan Youyu, Li Hui, Zhou Kai, Huang Hongwei, Li Ang, Zhuang Chunqiang, Wang Lihua, Zhang Ze, Han Xiaodong
Faculty of Materials and Manufacturing, Beijing Key Lab of Microstructure and Properties of Advanced Materials, Beijing University of Technology, Beijing, 100124, P. R. China.
Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, Jiangsu, 210008, P. R. China.
Adv Mater. 2022 Apr;34(17):e2109074. doi: 10.1002/adma.202109074. Epub 2022 Mar 17.
The photocatalytic CO reduction reaction is a sustainable route to the direct conversion of greenhouse gases into chemicals without additional energy consumption. Given the vast amount of greenhouse gas, numerous efforts have been devoted to developing inorganic photocatalysts, e.g., titanium dioxide (TiO ), due to their stability, low cost, and environmentally friendly properties. However, a more efficient TiO photocatalyst without noble metals is highly desirable for CO reduction, and it is both difficult and urgent to produce selectively valuable compounds. Here, a novel "single-atom site at the atomic step" strategy is developed by anchoring a single tungsten (W) atom site with oxygen-coordination at the intrinsic steps of classic TiO nanoparticles. The composition of active sites for CO reduction can be controlled by tuning the additional W to form W -O-Ti sites, resulting in both significant CO reduction efficiency with 60.6 μmol g h and selectivity for methane (CH ) over carbon monoxide (CO), which exceeds those of pristine TiO by more than one order of magnitude. The mechanism relies on the accurate control of the single-atom sites at step with 22.8% coverage of surface sites and the subsequent excellent electron-hole separation along with the favorable adsorption-desorption of intermediates at the sites.
光催化CO还原反应是一种将温室气体直接转化为化学品且无需额外能源消耗的可持续途径。鉴于温室气体的大量存在，人们致力于开发无机光催化剂，例如二氧化钛（TiO₂），因为它们具有稳定性、低成本和环境友好的特性。然而，对于CO还原而言，非常需要一种不含贵金属的更高效TiO₂光催化剂，并且生产具有选择性的有价值化合物既困难又紧迫。在此，通过在经典TiO₂纳米颗粒的本征台阶处锚定一个与氧配位的单钨（W）原子位点，开发了一种新颖的“原子台阶处的单原子位点”策略。通过调节额外的W形成W-O-Ti位点，可以控制用于CO还原的活性位点的组成，从而实现显著的CO还原效率，达到60.6 μmol g⁻¹ h⁻¹，并且对甲烷（CH₄）的选择性高于一氧化碳（CO），比原始TiO₂高出一个多数量级。其机理依赖于对覆盖率为22.8%的表面位点处的单原子位点的精确控制，以及随后优异的电子-空穴分离，同时位点处中间体具有良好的吸附-解吸性能。
