Wang Ye, Zhang Jiangwei, Shi Wen-Xiong, Zhuang Gui-Lin, Zhao Qiu-Ping, Ren Jing, Zhang Peng, Yin Hua-Qing, Lu Tong-Bu, Zhang Zhi-Ming
Institute for New Energy Materials and Low Carbon Technologies, School of Materials Science and Engineering, Tianjin University of Technology, Tianjin, 300384, China.
College of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot, 010021, P. R. China.
Adv Mater. 2022 Aug;34(33):e2204448. doi: 10.1002/adma.202204448. Epub 2022 Jul 17.
Solar-driven high-efficiency and direct conversion of methane into high-value-added liquid oxygenates against overoxidation remains a great challenge. Herein, facile and mass fabrication of low-cost tungsten single-atom photocatalysts is achieved by directly calcining urea and sodium tungstate under atmosphere (W-SA-PCN-m, urea amount m = 7.5, 15, 30, and 150 g). The single-atom photocatalysts can manage H O in situ generation and decomposition into ·OH, thus achieving highly efficient CH photooxidation in water vapor under mild conditions. Systematic investigations demonstrate that integration of multifunctions of methane activation, H O generation, and decomposition into one photocatalyst can dramatically promote methane conversion to C1 oxygenates with a yield as high as 4956 µmol g , superior to that of the most reported non-precious photocatalysts. Liquid-solid phase transition can induce the products to facilely switch in from HCOOH to CH OH by pulling the catalyst above water with CH OH/HCOOH ratio from 10% (in H O) to 80% (above H O).
太阳能驱动下将甲烷高效直接转化为高附加值液态含氧化合物并防止过氧化仍然是一项巨大挑战。在此，通过在大气氛围下直接煅烧尿素和钨酸钠（W-SA-PCN-m，尿素用量m = 7.5、15、30和150 g），实现了低成本钨单原子光催化剂的简便大规模制备。该单原子光催化剂能够原位调控H₂O的生成并分解为·OH，从而在温和条件下实现水蒸气中CH₄的高效光氧化。系统研究表明，将甲烷活化、H₂O生成和分解等多种功能整合到一种光催化剂中，可显著促进甲烷转化为C₁含氧化合物，产率高达4956 μmol g⁻¹，优于大多数已报道的非贵金属光催化剂。液-固相变可通过将催化剂置于水面上方，使产物中CH₃OH/HCOOH的比例从10%（在H₂O中）变为80%（在水面上方），从而使产物从HCOOH轻松转变为CH₃OH。
