Due to their excellent photoelectron chemical properties and suitable energy level alignment with perovskite,perylene diimide (PDI) derivatives are competitive non-fullerene electron transport material (ETM) candidates for perovskite solar cells (PSCs).However,the conjugated rigid plane structure of PDI units result in PDl-based ETMs tending to form large aggregates,limiting their application and photovoltaic performance.In this study,to restrict aggregation and further enhance the photovoltaic performance of PDl-type ETMs,two PDl-based ETMs,termed PDO-PDI2 (dimer) and PDO-PDI3 (trimer),were constructed by introducing a phenothiazine 5,5-dioxide (PDO) core building block.The research manifests that the optoelectronic properties and film formation property of PDO-PDI2 and PDO-PDI3 were deeply affected by the molecular spatial configuration.Applied in PSCs,PDO-PDI3 with threedimensional spiral molecular structure,exhibits superior electron extraction and transport properties,further achieving the best PCE of 18.72％ and maintaining 93％ of its initial efficiency after a 720-h aging test under ambient conditions.