Modifying morphology and defects of low-dimensional, semi-transparent perovskite thin films via solvent type

Jitprabhat Ponchai; Paphada Kaewurai; Chirapa Boonthum; Kusuma Pinsuwan; Thidarat Supasai; Somboon Sahasithiwat; Pongsakorn Kanjanaboos

doi:10.1039/c9ra00971j

Modifying morphology and defects of low-dimensional, semi-transparent perovskite thin films via solvent type

RSC Adv. 2019 Apr 16;9(21):12047-12054. doi: 10.1039/c9ra00971j. eCollection 2019 Apr 12.

Authors

Jitprabhat Ponchai¹, Paphada Kaewurai¹, Chirapa Boonthum¹, Kusuma Pinsuwan¹, Thidarat Supasai², Somboon Sahasithiwat³, Pongsakorn Kanjanaboos^{1

4}

Affiliations

¹ School of Materials Science and Innovation, Faculty of Science, Mahidol University Bangkok 10400 Thailand.
² Department of Materials Science, Faculty of Science, Kasetsart University Bangkok 10900 Thailand.
³ National Metal and Materials Technology Center (MTEC) Pathum Thani 12120 Thailand.
⁴ Center of Excellence for Innovation in Chemistry (PERCH-CIC), Office of Higher Education Commission, Ministry of Education (OHEC) Bangkok 10400 Thailand Pongsakorn.kan@mahidol.edu.

Abstract

(PEA)₂(MA) _n-1Pb _n I _n+1Br_2n perovskites are semi-transparent, color-tunable thin films with broader band gaps. They have the potential for semi-transparent solar cell and smart window applications. Solvent engineering significantly alters the morphology, absorbance, crystallinity, charge separation, and defects, thereby influencing the optoelectronic properties. Herein, we investigated the effect of the solvent type on the low dimensional, mixed halide perovskite thin films (n = 1, 3, and 5) and identified DMF : DMSO = 8 : 2 as the most suitable solvent. The mixed solvent regulated the growth rate of perovskites, which led to the smooth morphology and larger crystallite size. Through surface photovoltage spectroscopy and time resolved photoluminescence, good charge separation and low defects were linked to DD82 usage.