Flexible perovskite photodetector with room-temperatureself-healing capability without external trigger

Flexible perovskite photodetectors(FPDs)are promising for novel wearabledevices in bionics,robotics and health care.However,their performance degradationand instability during operations remain a grand challenge.Superiorflexibility and spontaneous functional repair of devices without the need forany external drive or intervention are ideal goals for FPDs.Herein,by usingphenyl disulfide instead of alkyl disulfide as a crosslinking agent,disulfidebonds with lower bond energy are introduced,thus endowing the polyurethanenetwork(SCPU)with the ability of self-healing at room temperature.SCPU is filled to the grain boundary of perovskite film,which not onlyimproves the crystal quality of perovskite and mechanical stability of FPD butalso enables FPD to self-heal at room temperature.As a result,the as-preparedFPD exhibits a superior responsivity of 0.4 A W^(-1),a high specific detectivity of 2.5×10^(11)Jones and 2μs fast response time in a self-powered mode.Moreimportantly,the FPD still retained 91%of the initial photo responsivity after9000 times of bending upon cyclic healing.This polymer doping strategy providesan effective solution for stable operation and room-temperature selfhealingfor FPDs.