Improving Performance and Stability of Planar Perovskite Solar Cells Through Passivation Effect with Green Additives

Abstract

Perovskite solar cells (PSCs) have debuted as the photovoltaic devices with the most potential and progress is being made at an unprecedented pace. Meanwhile, additive engineering is continuously pushing the power conversion efficiency (PCE) and device stability to higher levels by passivating defects and regulating crystallization behaviors. Considering the scalable fabrication of PSCs in the following stage, seeking green additives for optimizing perovskites is extremely valuable and paramount. Herein, we pioneer a green additive engineering method using fumaric acid (FMAC) to optimize the three‐cation perovskites to obtain highly efficient PSCs. FMAC not only optimizes crystallization behaviors to endow the perovskite films with a large grain size and few grain boundaries, but also forms a strong interaction with Pb2+/I− of the perovskites, thereby stabilizing the [PbI6]4− octahedral framework of the perovskite crystal lattices and effectively passivating the surface defects. On this basis, FMAC improves the photoelectric properties of perovskites and in particular, suppresses the nonradiative recombination. Consequently, the PCE of PSCs incorporating FMAC rises to 20.48%, exceeding that (19.18%) of the pristine device. In addition, FMAC also enhances the stability of PSCs. Therefore, we provide a significant strategy using a green additive to enhance the photovoltaic performance of PSCs.

A Novel Organic Phosphonate Additive Induced Stable and Efficient Perovskite Solar Cells with Efficiency over 24% Enabled by Synergetic Crystallization Promotion and Defect Passivation

“…The calculated electron defect density also decreases from 1.720 × 10 16 to 1.470 × 10 16 cm −3 , respectively. 67 In short, the DPPO molecule has the capability to reduce the hole defect density, hence inhibiting defect-induced carrier recombination, as seen by the PL and TRPL measurements.…”

“…A light-intensity-dependent J−V test was used to thoroughly evaluate the carrier recombination dynamics and charge transport process. 67 Figure 4i displays the relationship between V OC and logarithm of the incident light intensity (log I). V OC = εkT ln I/e + constant was the equation used to fit the data.…”

“…The estimated built-in potential ( V bi ) rose from 1.102 V for the control device to 1.133 V for the DPPO-modified device, implying that the driving force for carrier separation increased as a result of DPPO modification, which contributes to the DPPO-modified device’s high V OC . A light-intensity-dependent J – V test was used to thoroughly evaluate the carrier recombination dynamics and charge transport process Figure i displays the relationship between V OC and logarithm of the incident light intensity (log I ).…”

Efficient and hysteresis-free mixed-dimensional 2D/3D perovskite solar cells using ethyl lactate as a green additive to perovskite precursor solutions

“…It has been found that fumaric acid not only stabilizes the [PbI 6 ] 4− framework of the perovskite crystals and efficiently passivates the surface defects, but it also improves nucleation processes to endow the perovskites with large sized grains and few GBs. 28 Pengyun et al used a green and natural cellulose derivative containing hydrogen bonds into methylammonium lead iodide (MAPbI 3 ) precursors to serve as a bi-functional additive. Consequently, the compact and pinhole-less morphology of the cellulose-treated MAPbI 3 film with large sized crystals and passivated GBs is realized.…”

Reduction-Active Antisolvent: A Universal and Innovative Strategy of Further Ameliorating Additive Optimization for High Efficiency Perovskite Solar Cells

“…To date, many strategies for improving the photovoltaic performance and stability of PSCs have been reported, including mixed-halide engineering, , surface and interface passivation, − additive engineering, − selection of the charge-transport material, , and encapsulation . Among the aforementioned methodologies, additive engineering is considered the most effective and promising option because of the well-established intrinsic coordination ability of lead cations in the [PbI 6 ] 4– octahedral matrix of perovskites.…”