Lead-based perovskites have been regarded as an interesting class of semiconductors for owing to their excellent optical and electrical properties such as high absorption coefficient and long carrier lifetime. Based on their advantages, they have been utilized in various field of optoelectronics and shown great achievement in the solar cell especially. However, there are still limitations for the real application of lead-based perovskites: (i) the poor stability against humidity and UV-light (ii) the lead element which causes critical human toxicity

Lead-based perovskites are suffering from their intrinsic instability against the humidity and UV-light, resulting in their structural destruction, loss of their properties. In this regard, we suggest platinum complex as an encapsulating material which can absorb the UV region and exhibit hydrophobicity through the molecular design strategy. Furthermore, its high quantum yield promotes efficient energy transfer to perovskite, thereby enhancing the device performance. Both synergetic effects demonstrate the platinum complex as an excellent encapsulating material for perovskite.

The other issue of lead-based perovskites is the toxicity of lead element toward a human being. For this reason, some lead-free perovskites such as Cs2SnI6 have been developed but their mechanistic study for better utilization in the optoelectronics is not enough, unlike the lead-based perovskite. Thus, we show the charge transfer mechanism of Cs2SnI6 and its demonstration by using charge regeneration process in dye-sensitized solar cell, thereby suggesting how to improve the efficiency of Cs2SnI6-based device.

 

Keywords: lead-based perovskite, platinum complex, stability, energy transfer, lead-free perovskite, charge transfer mechanism.

 

1) Shin et al. Advanced Energy Materials, 1803243 (2018)