Lentz Levi C, Kolpak Alexie M
Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA, 02139, USA.
Sci Rep. 2017 Apr 28;7(1):1248. doi: 10.1038/s41598-017-01296-0.
The performance of bulk organic and hybrid organic-inorganic heterojunction photovoltaics is often limited by high carrier recombination arising from strongly bound excitons and low carrier mobility. Structuring materials to minimize the length scales required for exciton separation and carrier collection is therefore a promising approach for improving efficiency. In this work, first-principles computations are employed to design and characterize a new class of photovoltaic materials composed of layered transition metal phosphates (TMPs) covalently bound to organic absorber molecules to form nanostructured superlattices. Using a combination of transition metal substitution and organic functionalization, the electronic structure of these materials is systematically tuned to design a new hybrid photovoltaic material predicted to exhibit very low recombination due to the presence of a local electric field and spatially isolated, high mobility, two-dimensional electron and hole conducting channels. Furthermore, this material is predicted to have a large open-circuit voltage of 1.7 V. This work suggests that hybrid TMPs constitute an interesting class of materials for further investigation in the search for achieving high efficiency, high power, and low cost photo Zirconium phosphate was chosen, in part, due to previous experiment voltaics.
块状有机及有机-无机杂化异质结光伏电池的性能常常受到强束缚激子导致的高载流子复合以及低载流子迁移率的限制。因此，构建材料以最小化激子分离和载流子收集所需的长度尺度是提高效率的一种有前景的方法。在这项工作中，采用第一性原理计算来设计和表征一类新型光伏材料，该材料由与有机吸收分子共价结合形成纳米结构超晶格的层状过渡金属磷酸盐（TMP）组成。通过过渡金属取代和有机功能化的组合，系统地调整这些材料的电子结构，以设计一种新型杂化光伏材料，预计由于存在局部电场以及空间隔离的、高迁移率的二维电子和空穴传导通道，该材料将表现出非常低的复合率。此外，预计这种材料具有1.7 V的大开路电压。这项工作表明，杂化TMP构成了一类有趣的材料，可用于在寻找高效、高功率和低成本光伏电池的研究中作进一步研究。部分由于先前的实验，选择了磷酸锆。
