Interfacial Engineering for Efficient Low‐Temperature Flexible Perovskite Solar Cells

Abstract

Photovoltaic technology with low weight, high specific power in cold environments, and compatibility with flexible fabrication is highly desired for near‐space vehicles and polar region applications. Herein, we demonstrate efficient low‐temperature flexible perovskite solar cells by improving the interfacial contact between electron‐transport layer (ETL) and perovskite layer. We find that the adsorbed oxygen active sites and oxygen vacancies of flexible tin oxide (SnO2) ETL layer can be effectively decreased by incorporating a trace amount of titanium tetrachloride (TiCl4). The effective defects elimination at the interfacial increases the electron mobility of flexible SnO2 layer, regulates band alignment at the perovskite/SnO2 interface, induces larger perovskite crystal growth, and improves charge collection efficiency in a complete solar cell. Correspondingly, the improved interfacial contact transforms into high‐performance solar cells under one‐sun illumination (AM 1.5G) with efficiencies up to 23.7% at 218 K, which might open up a new era of application of this emerging flexible photovoltaic technology to low‐temperature environments such as near‐space and polar regions.

Benzoyl Sulfonyl Molecules for Bilateral Passivation and Crystalline Regulation at Buried Interfaces toward High‐Performance Perovskite Solar Cells

“…This indicates an improvement in both charge transfer and perovskite quality. [37] The integrated J SC values, obtained from EQE spectra, were 24.47 mA cm −2 for the K-SBA modified device and 23.56 mA cm −2 for the control device, closely aligning with their directly measured J SC values. The considerable enhancement in V OC and J SC , along with the reduced hysteresis observed in the K-SBA modified devices, stems from reduced recombination and improved charge transport, which can be attributed to the superior perovskite crystallinity, better interface contact, reduced defects, and enhanced energy band alignment at the buried interface (see Figures S13,S14, Supporting Information).…”

Annual research review of perovskite solar cells in 2023

“…Cai et al added trace amounts of titanium tetrachloride (TiCl 4 ) to SnO 2 to suppress adsorbed oxygen active sites and oxygen vacancies. The introduction of TiCl 4 helps to passivate defects, increase the conductivity of SnO 2 , optimize the band alignment of interface, and improve device charge extraction, thereby achieving a high PCE of 23.7% at 218 K. Moreover, the device maintained 89% of its initial PCE after 2500 cycles of bending with a 6 mm bending radius [185]. TSCs contain more than one light harvesting layer with different bandgaps.…”

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. 1–8 In particular, poly[bis(4-phenyl)(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. 9–12 The demonstrated power conversion efficiency (PCE) of inverted PSCs exceeded 26.1%.…”