Photonic Processing of MAPbI₃ Films by Flash Annealing and Rapid Growth for High‐Performance Perovskite Solar Cells

Abstract

Defects in polycrystalline halide perovskite films can cause a decrease of the solar cell photoconversion efficiency and stability. The perovskite film enhanced during crystal growth by controlling the processing method can alleviate defects and the related recombination sites that affect the performance of cells. Herein, flash infrared annealing is employed to crystallize methylammonium lead iodide perovskite with a single heating pulse, where uniform grain domains are optically observed and mapped. Films are annealed with different temperature ramps up to 48 °C s−1 heating rate. Annealing with higher heating rates presents lower defect densities, decreases the Urbach energy tail, and improves the optoelectrical performance of the films. These improvements are rationalized by Raman spectroscopy of nucleation points and grain surface differences among the process variations. The role of crystal growth and subsequent film quality allows to achieve a champion photovoltaic device growth at 48 °C s−1 with stability around 250 h under 1 sun illumination and 60% relative humidity for 100 h under 3 sun (AM1.5G) illumination. In situ optical imaging is recorded during the process, confirming that rapid annealing, i.e., higher heating rates, contributes to obtain more stable devices with the added advantage of shorter processing time.

Recent Advances in the Photonic Curing of the Hole Transport Layer, the Electron Transport Layer, and the Perovskite Layers to Improve the Performance of Perovskite Solar Cells

“…Notably, PC reduces surface bulk defects and enhances light absorption, resulting in denser films and influencing the performance of PSCs [10,70]. Other studies also highlight PC's role in defect mitigation and absorption enhancement [71]. Bulk defect attenuation improves the crystallinity and stability, as well as the alignment of energy levels, enabling efficient charge extraction [72].…”

Orthorhombic lead-free hybrid perovskite CH3NH3SnI3 under strain: an ab initio study

“…was noticed while this bond was analyzed in the O-CD 3 ND 3 PbI 3 compounds. 71 We can see that applying tensile strain enhances region (2), but it appears to be concentrated around the non-covalent region, suggesting that the tilting Fig. 5 The evolution of band gap and binding energy as a function of strain.…”

“…In recent years, the advent of perovskite solar cells based on hybrid halide perovskites has revolutionized the eld of photovoltaic (PV) solar cells. 1,2 In particular the synthesis [3][4][5] of lead-free methylammonium tin iodide CH 3 NH 3 SnI 3 opened new avenues for photovoltaic materials. To be efficiently used in PV applications, a semiconductor material should have a high light absorption (∼10 5 cm −1 for >1.4 eV).…”

Recent Progress in Perovskite Solar Cells: Status and Future

“…Chen et al [158] adopted a rapid microwave-annealing method to avoid miscellaneous phases. Serafini et al [159] proposed that flash infrared annealing could promote the optoelectrical property of the perovskite. Turgut et al [160] proposed a light-assisted annealing (LA) method to form larger and uniform grains of the perovskite layer.…”