콘텐츠 본문
논문 해외 국제전문학술지(SCI급) Dual-Site Compositional Engineering of Bismuth-Based Halide Perovskites for Stable and Efficient Lead-free Solar Cells
- 학술지 구분 국제전문학술지(SCI급)
- 게재년월 2021-06
- 저자명 홍기하공동(교신),박종구
- 학술지명 JOURNAL OF PHYSICAL CHEMISTRY C
- 발행처명 AMER CHEMICAL SOC
- 발행국가 해외
- 논문언어 외국어
- 전체저자수 2
논문 초록 (Abstract)
The toxicity of lead in metal halide perovskite solar cells is considered the most critical technical barrier for their commercialization. Among the candidates to replace Pb, trivalent cations (e.g., Bi3+ and Sb3+) are attracting considerable interest owing to their excellent reliability and favorable optical performance. Trivalent cation-based lead-free halide perovskites have two polymorphs: 0D phase (dimer, P63/mmc) and 2D phase (layered, P3m1). The 2D phase has a lower band gap and is preferred for carrier transport; however, its phase stability at room temperature remains a challenge. This study investigated the effects of dual-site compositional mixing on the stabilization of the 2D phase of A3Bi2X9 (A = Cs, methylammonium (MA), formamidinium (FA); X = I, Br, Cl) and electronic structure modulation. Cl mixing was noted to be essential in creating a stable 2D phase. MA mixing can be applied to reduce the band gap widening for the Cl-mixed perovskites. We suggest the optimal criterion as Cs3−χMAχBi2I9–yCly, with χ < 0.1 and y > 0.3.
