Carrier Interfacial Engineering by Bismuth Modification for Efficient and Thermoresistant Perovskite Solar Cells

Abstract

Organic–inorganic halide perovskite solar cells (PSCs) have emerged as attractive alternatives to conventional solar cells. It is still a challenge to obtain PSCs with good thermal stability and high permanence, especially at extreme outdoor temperatures. This work systematically studies the effects of Bi3+ modification on structural, electrical, and optical properties of perovskite films (FA0.83MA0.17Pb(I0.83Br0.17)3) and the performance of corresponding PSCs. The results indicate that Bi3+ modified PSCs can achieve better thermal stability, photovoltaic response, and reproducibility compared with control cells due to the decreased grain boundaries, enhanced crystallization, and improved electron extraction from perovskite film. As a result, the modified PSC exhibits an optimized power conversion efficiency (PCE) of 19.4% compared with 18.3% for the optimized control device, accompanied by better thermoresistant ability under 100–180 °C and enhanced long‐term stability. The degradation rate of the modified device is reduced by an order of magnitude due to effective structural defect modification in perovskite photoactive layer. It could maintain more than two months at 60 °C. These results shed light on the origin of crystallization and thermal stability of perovskite films, and provide an approach to solve thermal stability issue of PSCs.

Causes and Solutions of Recombination in Perovskite Solar Cells

“…In the past, tremendous efforts have contributed to investigate partial replacement of Pb 2+ (ion radius: 1.49 Å) by Sn 2+ (ion radius: 1.35 Å) for the purpose of extending the absorption onset and reducing toxicity of lead . Although the absorption spectrum is much extended, the device based on Sn suffers from poor chemical stability due to oxidation of Sn 2+ to Sn 4+ in the presence of oxygen and moreover poor PCE because of fast electron/hole recombination . Encouraged by both development of lead‐free or lead‐less perovskite, other (transition) metal ions were also employed to partially substitute Pb 2+ .…”

“…Although the absorption spectrum is much extended, the device based on Sn suffers from poor chemical stability due to oxidation of Sn 2+ to Sn 4+ in the presence of oxygen and moreover poor PCE because of fast electron/hole recombination . Encouraged by both development of lead‐free or lead‐less perovskite, other (transition) metal ions were also employed to partially substitute Pb 2+ . Although In 3+ is somewhat difficult to replace in part Pb 2+ due to charge imbalance, excess charge was tried to compensate by adding additional anion such as Cl, leading to MAPb 1− x In x I 3 Cl x , which was applied in inverted planar PSCs (Table ).…”

Tailoring electrical property of the low-temperature processed SnO2 for high-performance perovskite solar cells

“…The retarded recombination was also manifested by the lower dark current density as illustrated in Fig. S6, which indicated that the Nb 5+ doping in SnO 2 could reduce the energy loss caused by the non-radiative recombination, resulting in the enhanced FF and V OC [42,43]. Thus, we concluded two aspects responsible for the enhanced devices performance.…”

Bismuth Halide Perovskite‐Like Materials: Current Opportunities and Challenges

“…[38] The crystallinity,e lectron extraction and structural stability of FAI 0.83 MA 0.17 Pb(I 0.83 Br 0.17 ) 3 perovskite film can be significantly improvedb ya dding MA 3 Bi 2 Br 9 into the precursor solution ( Figure 17). [39] The enhanced PCE of the MA 3 Bi 2 Br 9 -modified device was ascribed to reduced lattice defects, enlarged grain size, and increased electron extraction efficiency. Therefore, the incorporation of Bi 3 + in 3D Pb-based perovskites is promising approachtoi mprove the efficiency and stability of PSCs.…”

“…The 2 D MA 3 Bi 2 I 9 /3 D MAPbI 3 heterostructured PSCs exhibited a high PCE of 19.87 % along with reduced hysteresis and improved air stability, combining the advantages of the high‐performance of MAPbI 3 and the stability of MA 3 Bi 2 I 9 (Figure ) . The crystallinity, electron extraction and structural stability of FAI 0.83 MA 0.17 Pb(I 0.83 Br 0.17 ) 3 perovskite film can be significantly improved by adding MA 3 Bi 2 Br 9 into the precursor solution (Figure ) . The enhanced PCE of the MA 3 Bi 2 Br 9 ‐modified device was ascribed to reduced lattice defects, enlarged grain size, and increased electron extraction efficiency.…”