Lin Yixiong, Avvacumova Mariana, Zhao Ruilin, Chen Xihan, Beard Matthew C, Yan Yong
Department of Chemistry and Biochemistry, San Diego State University, San Diego, California 92182, United States.
National Renewable Energy Laboratory, Golden, Colorado 80401, United States.
ACS Appl Mater Interfaces. 2022 Jun 8;14(22):25357-25365. doi: 10.1021/acsami.2c03411. Epub 2022 May 24.
Triplet excitons are generally confined within a semiconductor. Hence, solar energy utilization via direct triplet energy transfer (TET) from semiconductors is challenging. TET from lead halide perovskite semiconductors to nearby organic molecules has been illustrated with ultrafast spectroscopy. Direct utilization of solar energy, , visible light, via TET for photocatalysis is an important route but has not yet been demonstrated with lead halide perovskite semiconductors. Here, we show that a photocatalytic reaction, focusing on a 2 + 2 cycloaddition reaction, can been successfully demonstrated via TET from lead halide perovskite nanocrystals (PNCs). The triplet excitons are shown to induce a highly diastereomeric -selective 2 + 2 cycloaddition starting from olefins. Such photocatalytic reactions probe the TET process previously only observed spectroscopically. Moreover, our observation demonstrates that bulk-like PNCs (size, >10 nm; PL = 530 nm), in addition to quantum-confined smaller PNCs, are also effective for TET. Our findings may render a new energy conversion pathway to employ PNCs via direct TET for photocatalytic organic synthesis.
三重态激子通常被限制在半导体内部。因此，通过半导体的直接三重态能量转移（TET）来利用太阳能具有挑战性。利用超快光谱已证实了从卤化铅钙钛矿半导体到附近有机分子的TET。通过TET直接利用太阳能（即可见光）进行光催化是一条重要途径，但尚未在卤化铅钙钛矿半导体中得到证实。在此，我们表明，聚焦于2 + 2环加成反应的光催化反应能够通过卤化铅钙钛矿纳米晶体（PNCs）的TET成功实现。结果表明，三重态激子能引发从烯烃开始的高度非对映选择性2 + 2环加成反应。此类光催化反应探测了此前仅在光谱学上观察到的TET过程。此外，我们的观察结果表明，除了量子限制的较小PNCs外，块状PNCs（尺寸>10 nm；PL = 530 nm）对TET也有效。我们的发现可能为通过直接TET利用PNCs进行光催化有机合成提供一条新的能量转换途径。
