Enhanced photocatalytic N2 fixation via defective and fluoride modified TiO2 surface
Enhanced photocatalytic N2 fixation via defective and fluoride modified TiO2 surface
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通过有缺陷和氟化物改性的 TiO2 表面增强光催化 N-2 固定
DOI：
10.1016/j.apcatb.2020.119580
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发表时间：
2021-03-01
影响因子：
22.1
通讯作者：
Sun, Zaicheng
中科院分区：
文献类型：
--
作者：
Guan, Renquan;Wang, Dandan;Sun, Zaicheng
光催化固氮（PNF）提供了一种低成本的氨生成途径。由于N-2分子浓度低，光子到氨的转换效率差，严重阻碍了这一步的前进。在此，我们展示了一种具有表面氧空位（Vo）和F改性表面的光催化剂，以促进催化剂表面上的N-2吸附和活化。Vo位促进了N-2的化学吸附，电子从催化剂转移到N-2。F改性将TiO 2表面性质从亲水性转变为好氧性，从而促进了N-2的吸附。同时，氢还原反应（HER）被抑制，因为质子难以吸附在F覆盖的表面上。最佳的NH3产生速率可达到206 μ molh（-1）g（-1），这比纯TiO 2纳米颗粒的NH3产生速率（类似于23 μ molh（-1）g（-1））高9倍。该报告提供了一个潜在的策略，以克服传质限制，实现高转化效率的PNF。
Photocatalytic N-2 fixation (PNF) provides a low-cost route to generate ammonia. The poor conversion efficiency from photon to ammonia seriously hinders the step forward because of the low concentration of N-2 molecules. Herein, we demonstrate a photocatalyst with surface oxygen vacancies (Vo) and a F modified surface to facilitate N-2 adsorption and activation on the surface of catalysts. The Vo site promotes the chemical adsorption of N-2, electron transfer from catalyst to N-2. F modification switches the TiO2 surface properties from hydrophilic to aerophilic, thus facilitating the adsorption of N-2. Meanwhile, the hydrogen reduction reaction (HER) is sup-pressed, as protons hard to adsorb on F capped surfaces. The optimal NH3 production rate can reach 206 mu molh(-1)g(-1), which is similar to 9 times higher than that of pure TiO2 nanoparticles (similar to 23 mu molh(-1)g(-1)). This report provides a potential strategy to overcome mass transfer limitation and achieve a high conversion efficiency in PNF.