Brandt Riley E, Kurchin Rachel C, Hoye Robert L Z, Poindexter Jeremy R, Wilson Mark W B, Sulekar Soumitra, Lenahan Frances, Yen Patricia X T, Stevanović Vladan, Nino Juan C, Bawendi Moungi G, Buonassisi Tonio
Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
University of Florida , Gainesville, Florida 32611, United States.
J Phys Chem Lett. 2015 Nov 5;6(21):4297-302. doi: 10.1021/acs.jpclett.5b02022. Epub 2015 Oct 15.
Guided by predictive discovery framework, we investigate bismuth triiodide (BiI3) as a candidate thin-film photovoltaic (PV) absorber. BiI3 was chosen for its optical properties and the potential for "defect-tolerant" charge transport properties, which we test experimentally by measuring optical absorption and recombination lifetimes. We synthesize phase-pure BiI3 thin films by physical vapor transport and solution processing and single-crystals by an electrodynamic gradient vertical Bridgman method. The bandgap of these materials is ∼1.8 eV, and they demonstrate room-temperature band-edge photoluminescence. We measure monoexponential recombination lifetimes in the range of 180-240 ps for thin films, and longer, multiexponential dynamics for single crystals, with time constants up to 1.3 to 1.5 ns. We discuss the outstanding challenges to developing BiI3 PVs, including mechanical and electrical properties, which can also inform future selection of candidate PV absorbers.
在预测性发现框架的指导下，我们研究了三碘化铋（BiI3）作为薄膜光伏（PV）吸收体的候选材料。选择BiI3是因其光学性质以及具有“缺陷容忍”电荷传输性质的潜力，我们通过测量光吸收和复合寿命进行实验测试。我们通过物理气相传输和溶液处理合成了相纯的BiI3薄膜，并通过电动梯度垂直布里奇曼法制备了单晶。这些材料的带隙约为1.8 eV，并且在室温下表现出带边光致发光。我们测量了薄膜的单指数复合寿命在180 - 240 ps范围内，而单晶则呈现更长的多指数动力学，时间常数高达1.3至1.5 ns。我们讨论了开发BiI3光伏器件面临的突出挑战，包括机械和电学性质，这也可为未来候选光伏吸收体的选择提供参考。
