Department of Physics, University of Oxford , Clarendon Laboratory, Parks Road, Oxford, United Kingdom.
Nano Lett. 2013 Sep 11;13(9):4505-10. doi: 10.1021/nl4024287. Epub 2013 Aug 19.
Recently, inorganic and hybrid light absorbers such as quantum dots and organometal halide perovskites have been studied and applied in fabricating thin-film photovoltaic devices because of their low-cost and potential for high efficiency. Further boosting the performance of solution processed thin-film solar cells without detrimentally increasing the complexity of the device architecture is critically important for commercialization. Here, we demonstrate photocurrent and efficiency enhancement in meso-superstructured organometal halide perovskite solar cells incorporating core-shell Au@SiO2 nanoparticles (NPs) delivering a device efficiency of up to 11.4%. We attribute the origin of enhanced photocurrent to a previously unobserved and unexpected mechanism of reduced exciton binding energy with the incorporation of the metal nanoparticles, rather than enhanced light absorption. Our findings represent a new aspect and lever for the application of metal nanoparticles in photovoltaics and could lead to facile tuning of exciton binding energies in perovskite semiconductors.
最近，由于成本低、效率高，量子点和有机金属卤化物钙钛矿等无机和混合光吸收体被用于制造薄膜光伏器件，并得到了研究和应用。对于实现商业化而言，在不增加器件结构复杂性的前提下，进一步提高溶液处理薄膜太阳能电池的性能至关重要。在这里，我们证明了在包含核壳 Au@SiO2 纳米颗粒（NPs）的介观超结构有机金属卤化物钙钛矿太阳能电池中，光电流和效率得到了增强，器件效率高达 11.4%。我们将光电流增强的原因归因于一种以前未观察到的、意想不到的机制，即金属纳米颗粒的掺入降低了激子结合能，而不是增强了光吸收。我们的发现代表了金属纳米颗粒在光伏中的应用的一个新方面和新途径，并可能导致钙钛矿半导体中激子结合能的简便调节。
