Realizing 23.9% Flexible Perovskite Solar Cells via Alleviating the Residual Strain Induced by Delayed Heat Transfer

Abstract

Flexible perovskite solar cells (pero-SCs) have aroused widespread interest because of their unique advantages in lightweight and portable electronics applications. However, the delayed heat transfer caused by plastic substrates can severely affect the reaction activity and diffusivity of cations during perovskite growth, resulting in spatial composition inhomogeneity and residual strain in the perovskite film. Here, a cross-linker 4,5-(3-methyloxetane) dicarboxylate imidazole (MZ) is designed to regulate crystallization kinetics precisely for controlling composition distribution in perovskite films on plastic substrates. The MZ can coordinate with Pb 2+ to form a mesoporous scaffold of lead iodide film and increase the activation energy for perovskite crystal formation, which can inhibit cation reaction in the top region and accelerate their downward diffusion. Consequently, the compositional inhomogeneity and residual strain can be effectively alleviated. Finally, the 0.062 and 1.004 cm 2 flexible pero-SCs achieved record power conversion efficiencies of 23.94% (certified 23.57%) and 21.87% with enhanced operational and mechanical stability.

Recent Advances in Quality Strengthening of Perovskite Films by Additive Engineering for Efficient Solar Cells

“…Similar to this work, a small molecule 4,5‐(3‐methyloxetane) dicarboxylate imidazole (MZ) with carboxyl, imidazole, and oxetane groups was also used as a crosslinking monomer to precisely regulate the crystallization kinetics of perovskite films to control the composition distribution in perovskite films on flexible substrates. [ 119 ] The CO and CN groups in imidazole can coordinate with Pb 2+ to form a PbI 2 mesoporous scaffold and increase the activation energy of perovskite crystal formation, which can inhibit the cation reaction in the top region of perovskite film and accelerate its downward diffusion at low temperature. In addition, the crosslinked MZ filled in the perovskite grain boundary can release the mechanical stress of the perovskite film to enhance the mechanical stability of the modified FPSCs.…”

“…I) PCE decay of the FPSCs versus bending cycles with a radius of 5 mm. Reproduced with permission [119]. Copyright 2023, American Chemical Society.…”

Comprehensive interface engineering based on target anchoring agents for efficient and stable inverted perovskite solar cells

“…Inverted PSCs have garnered considerable interest because of their negligible hysteresis and potential for tandem solar cells combining various photovoltaic technologies such as silicon, CuInGaSe 2 and perovskites. [1][2][3][4][5][6][7][8] In particular, poly[bis(4phenyl)(2,4,6-trimethylphenyl)amine] (PTAA) has emerged as one of the most promising materials for the fabrication of hole transport layers (HTLs) in PSCs owing to its ease of formation, transparency to visible light and ideal hole mobility. [9][10][11][12] The demonstrated power conversion efficiency (PCE) of inverted PSCs exceeded 26.1%.…”

Flexible, Transparent, and Bifacial Perovskite Solar Cells and Modules Using the Wide-Band Gap FAPbBr3 Perovskite Absorber

“…Solar energy is a promising solution, and photovoltaic (PV) technology has made significant progress in recent years. Perovskite solar cells (PSCs) have achieved impressive power conversion efficiencies (PCEs) of up to 26% in a short time frame. , The low-temperature processability of PSCs has facilitated the development of flexible PSCs (flex-PSCs), adding significant advantages over conventional photovoltaics. − Due to their low cost, − high power-to-weight ratio, , and mechanical robustness, , flex-PSCs are beneficial for areas where conventional photovoltaics are impractical such as wearable technology, portable power sources, , space applications, , and Internet of things (IoT). , In addition, flex-PSCs are compatible with scalable and cost-effective manufacturing methods, like roll-to-roll printing techniques. , …”