Journal of Physical Chemistry C
Journal of Physical Chemistry C
5 years ago

The Effect of Stoichiometry on the Stability of Inorganic Cesium Lead Mixed-Halide Perovskites Solar Cells

The Effect of Stoichiometry on the Stability of Inorganic Cesium Lead Mixed-Halide Perovskites Solar Cells
Sheng Chen, Qingshan Ma, Kylie Catchpole, Xiaofan Deng, Mark N. Lockrey, Shujuan Huang, Jizhong Yao, Yuchao Shan, Martin A. Green, Meng Zhang, Anita W. Y. Ho-Baillie, Jianghui Zheng, Cho Fai Jonathan Lau, Hemant K. Mulmudi
Metal halide perovskite solar cells that use the inorganic cation Cs have been shown to have better thermal stability than the organic cation containing counterparts, and CsPbI2Br has a more suitable (lower) band gap than CsPbIBr2 as a photovoltaic energy harvesting material. However, increase in iodine content reduces structural stability due to the preference toward the non-perovskite orthorhombic phase when the film is exposed to air. In this work, the effect of varying stoichiometry of CsPbI2Br perovskite on film quality such as the grain size, presence of impurities and nature of impurity grains, photoluminescence, morphology, and elemental distribution are studied. Details on how to vary the stoichiometry during the dual source thermal evaporation process are reported. It is found that the air stability of CsPbI2Br film correlates with the CsBr-to-PbI2 deposition rate ratio, in which the CsBr-rich CsPbI2Br is the most stable upon air exposure, while the stoichiometrically balanced CsPbI2Br perovskite film gives the best photovoltaic performance. The encapsulated device maintains 90% of the initial performance after 240 h damp and heat test at 85 °C and 85% relative humidity.

Publisher URL: http://dx.doi.org/10.1021/acs.jpcc.7b06268

DOI: 10.1021/acs.jpcc.7b06268

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.