由p-型块体晶粒薄膜和n-型纳米晶粒薄膜组成的体/纳结构平板异质结（BnPHJ）薄膜，是高效无机太阳电池中常用的典型光活性层结构，是电池的关键材料部分；然而，无机BnPHJ薄膜太阳电池在光电转换过程中的许多基础性问题还缺乏深入的理解。本项目以易低成本大面积制备的高效无机异质结薄膜太阳电池为目标牵引，通过溶液法在n-型金属氧化物纳米晶粒薄膜上可控原位生长p-型金属硫属化物块体晶粒薄膜，来制备无机BnPHJ薄膜并实现其结构与功能的调控；通过联合超快瞬态吸收光谱和动态光电化学谱技术，实验与理论相结合，全面深入理解p-型块体晶粒薄膜结构特性相关的载流子过程和光伏原理，揭示电池性能的关键决定因素和物理机制；发展新型电池制备技术，获得效率为9-10%的无机BnPHJ薄膜太阳电池原型器件。本项目的实施可促进低价、稳定、高效太阳电池的发展。

Bulk/nano-planar heterojunction (BnPHJ) films, consisting of sequentially stacked p-type bulk gain film and n-type nanocrystal film on top of each other, are commonly used as the typical and key photoactive layers in efficient inorganic solar cells. However, many basic issues still remain unclear in the inorganic BnPHJ film solar cells. This project aims at the access to efficient inorganic heterojunction film solar cells that are easily prepared on a large scale at low cost. For this purpose, high-quality BnPHJ films with tailored structural characteristics and functions are controllably prepared by solution-processing strategy, featuring the in-situ growth of bulk grain films of p-type metal chalcogenides over the nanocrystal films of metal oxides; by using transient absorption spectroscopy (TAS) to experimentally observe the ultrafast processes and dynamic optoelectrochemical spectroscopy to detect the relatively slow processes, with the combinational studies of experimental and theoretical and data, the charge carrier processes and photovoltaic principles correlated with the structural characteristics of BnPHJ films are comprehensively understood, and the key factors and the related physical principles governing the device performances are revealed, providing the scientific bases for optimization of device structure; the technology for assembling novel solar cells is developed for the prototypal devices of inorganic BnPHJ film solar cells with a power conversion efficiency of 9-10%. Implementation of this project can promote the development of low-cost, stable and efficient solar cells.