Daily temperature variations induce phase transitions and lattice strains in halide perovskites, challenging their stability in solar cells. We stabilized the perovskite black phase and improved solar cell performance using the ordered dipolar structure of β-poly(1,1-difluoroethylene) to control perovskite film crystallization and energy alignment. We demonstrated p-i-n perovskite solar cells with a record power conversion efficiency of 24.6% over 18 square millimeters and 23.1% over 1 square centimeter, which retained 96 and 88% of the efficiency after 1000 hours of 1-sun maximum power point tracking at 25° and 75°C, respectively. Devices under rapid thermal cycling between −60° and +80°C showed no sign of fatigue, demonstrating the impact of the ordered dipolar structure on the operational stability of perovskite solar cells.

Halide perovskites are crystalline semiconductors with exceptional optoelectronic properties, rapidly developing toward large‐scale applications. Lead (II) (Pb²⁺) is the core element used to prepare halide perovskites. Pb²⁺ can displace key 2+ elements, including calcium, zinc and iron, that regulate vital physiological functions. Sn²⁺ can replace Pb²⁺ within the perovskite structure and, if accidentally dispersed in the environment, it readily oxidizes to Sn⁴⁺, which is compatible with physiological functions and thus potentially safe. The 3+ salt bismuth (III) (Bi³⁺) is also potentially safe for the same reason and useful to prepare double perovskites. Here, this work studies the biotoxicity of Pb, Sn, and Bi perovskites in mice for the first time. This work analyses histopathology and growth of mice directly exposed to perovskites and investigate the development of their offspring generation. This study provides the screening of organs and key physiological functions targeted by perovskite exposure to design specific studies in mammalians.

Tin halide perovskites are an appealing alternative to lead perovskites. However, owing to the lower redox potential of Sn(II)/Sn(IV), particularly under the presence of oxygen and water, the accumulation of Sn(IV) at the surface layer will negatively impact the device's performance and stability. To this end, this work has introduced a novel multifunctional molecule, 1,4‐phenyldimethylammonium dibromide diamine (phDMADBr), to form a protective layer on the surface of Sn‐based perovskite films. Strong interactions between phDMADBr and the perovskite surface improve electron transfer, passivating uncoordinated Sn(II), and fortify against water and oxygen. In situ grazing incidence wide‐angle X‐ray scattering (GIWAXS) analysis confirms the enhanced thermal stability of the quasi‐2D phase, and hence the overall enhanced stability of the perovskite. Long‐term stability in devices is achieved, retaining over 90% of the original efficiency for more than 200 hours in a 10% RH moisture N₂ environment. These findings propose a new approach to enhance the operational stability of Sn‐based perovskite devices, offering a strategy in advancing lead‐free optoelectronic applications.

As a novel technology, perovskite solar cells (PSCs) have attracted worldwide attention due to their high photoelectric conversion efficiency (PCE) and low fabricating cost. Moreover, with the development of this technology, PSCs have achieved a great breakthrough in PCE. However, the heavy metal element Pb in PSCs does harm to human health and ecological environments, which restricts the further application of Pb-based PSCs. Under certain circumstances, the leakage of lead will cause serious pollution to the environment. The purpose of this review is to summary and discuss the way of lead leakage suppression. Among them, we pay more attention to the method of packaging technology, chemisorption procession and the limitations of each method. Finally, strategies of highly PCE and non-toxic perovskite devices are proposed.