Atmospheric CO2 capture and photofixation to near-unity CO by Ti3+-Vo-Ti3+ sites confined in TiO2 ultrathin layers

• 作者: Liang Liang Peiquan Ling Yuhuan Li Li Li Jiandang Liu Qiquan Luo Hongjun Zhang Qian Xu Yang Pan Junfa Zhu Bangjiao Ye Yongfu Sun
• 来源期刊: 中国科学：化学（英文版）
• 年，卷（期）: 2021,（6）
• 所属期刊栏目: COMMUNICATIONS
• 页码范围: 953-958
• 页数: 6页
• 语种: 英文

摘要

To realize efficient atmospheric CO2 chemisorption and activation,abundant Ti3+ sites and oxygen vacancies in TiO2 ultrathin layers were designed.Positron annihilation lifetime spectroscopy and theoretical calculations first unveil each oxygen vacancy is associated with the formation of two Ti3+ sites,giving a Ti3+-Vo-Ti3+ configuration.The Ti3+-Vo-Ti3+ sites could bond with CO2 molecules to form a stable configuration,which converted the endoergic chemisorption step to an exoergic process,verified by in-situ Fourier-transform infrared spectra and theoretical calculations.Also,the adjacent Yi3+ sites not only favor CO2 activation into COOH* via forming a stable Ti3+--C-O-Ti3+ configuration,but also facilitate the rate-limiting COOH* scission to CO* by reducing the energy barrier from 0.75 to 0.45 eV.Thus,the Ti3+-Vo-TiOz ultrathinlayers could directly capture and photofix atmospheric CO2 into near-unity CO,with the corresponding CO2-to-CO conversion ratio of ca.20.2％.