Lin Cheng-Chieh, Liu Ting-Ran, Lin Sin-Rong, Boopathi Karunakara Moorthy, Chiang Chun-Hao, Tzeng Wen-Yen, Chien Wan-Hsiu Chang, Hsu Hua-Shu, Luo Chih-Wei, Tsai Hui-Ying, Chen Hsin-An, Kuo Pai-Chia, Shiue Jessie, Chiou Jau-Wern, Pong Way-Faung, Chen Chia-Chun, Chen Chun-Wei
International Graduate Program of Molecular Science and Technology, National Taiwan University (NTU-MST), Taipei 10617, Taiwan.
Molecular Science and Technology Program, Taiwan International Graduate Program (TIGP), Academia Sinica, Taipei 11529, Taiwan.
J Am Chem Soc. 2022 Aug 31;144(34):15718-15726. doi: 10.1021/jacs.2c06060. Epub 2022 Aug 17.
"Spin" has been recently reported as an important degree of electronic freedom to improve the performance of electrocatalysts and photocatalysts. This work demonstrates the manipulations of spin-polarized electrons in CsPbBr halide perovskite nanoplates (NPLs) to boost the photocatalytic CO reduction reaction (CORR) efficiencies by doping manganese cations (Mn) and applying an external magnetic field. Mn-doped CsPbBr (Mn-CsPbBr) NPLs exhibit an outstanding photocatalytic CORR compared to pristine CsPbBr NPLs due to creating spin-polarized electrons after Mn doping. Notably, the photocatalytic CORR of Mn-CsPbBr NPLs is significantly enhanced by applying an external magnetic field. Mn-CsPbBr NPLs exhibit 5.7 times improved performance of photocatalytic CORR under a magnetic field of 300 mT with a permanent magnet compared to pristine CsPbBr NPLs. The corresponding mechanism is systematically investigated by magnetic circular dichroism spectroscopy, ultrafast transient absorption spectroscopy, and density functional theory simulation. The origin of enhanced photocatalytic CORR efficiencies of Mn-CsPbBr NPLs is due to the increased number of spin-polarized photoexcited carriers by synergistic doping of the magnetic elements and applying a magnetic field, resulting in prolonged carrier lifetime and suppressed charge recombination. Our result shows that manipulating spin-polarized electrons in photocatalytic semiconductors provides an effective strategy to boost photocatalytic CORR efficiencies.
最近有报道称，“自旋”作为一种重要的电子自由度，可用于提高电催化剂和光催化剂的性能。这项工作展示了在CsPbBr卤化物钙钛矿纳米片（NPLs）中对自旋极化电子的操控，通过掺杂锰阳离子（Mn）和施加外部磁场来提高光催化CO还原反应（CORR）的效率。与原始的CsPbBr NPLs相比，Mn掺杂的CsPbBr（Mn-CsPbBr）NPLs表现出出色的光催化CORR，这是由于Mn掺杂后产生了自旋极化电子。值得注意的是，施加外部磁场显著增强了Mn-CsPbBr NPLs的光催化CORR。与原始的CsPbBr NPLs相比，在300 mT的永磁磁场下，Mn-CsPbBr NPLs的光催化CORR性能提高了5.7倍。通过磁圆二色光谱、超快瞬态吸收光谱和密度泛函理论模拟系统地研究了相应的机理。Mn-CsPbBr NPLs光催化CORR效率提高的原因是通过磁性元素的协同掺杂和施加磁场增加了自旋极化光激发载流子的数量，从而延长了载流子寿命并抑制了电荷复合。我们的结果表明，在光催化半导体中操控自旋极化电子为提高光催化CORR效率提供了一种有效策略。
