钙钛矿太阳能电池二氧化锡电子传输层的改性策略综述OA

Perovskite solar cells(PSCs)have emerged as a prominent research hotspot in the photovol-taic field due to their high extinction coefficient and carrier mobility.Tin dioxide(SnO2)is regarded as a highly promising electron transport layer(ETL)material owing to its high electron mobility,excel-lent light transmittance,and suitable energy level alignment.However,the presence of surface defects in SnO2 films severely restricts the further enhancement of device efficiency and long-term stability.This review systematically summarizes three core categories of defects in SnO2 ETLs and their corre-sponding modification strategies.Regarding particle agglomeration and surface roughness,the mecha-nisms of suppressing particle aggregation and reducing roughness through small molecules/polymers(e.g.,TFE,DLAM,PAM)via coordination bonding,electrostatic repulsion,and steric hindrance effects are elucidated.For the removal of residual surface hydroxyls(—OH),strategies such as halogen ion(F-,Cl-)exchange and neutralization reactions to form stable Sn-X bonds and eliminate deep-level traps are discussed.To address oxygen vacancies and dangling bonds,methods including surface coordination passivation(e.g.,L-carnitine,NH4 PF6),overlayer coating(e.g.,TiO2),and heterovalent metal ion(e.g.,Ni,Y)doping are summarized.Furthermore,the physicochemical mechanisms of these modifications and their impacts on power conversion efficiency(PCE)are comprehensively compared.Finally,future research directions are proposed,highlighting that in-depth analysis of passivation mechanisms,development of multifunctional passivation molecules,and resolution of process compati-bility for large-area fabrication are crucial for the industrialization of SnO2-based PSCs.