Coating　the　perovskite　layer　via　a　two-step　method　is　an　adaptable　solution　for　industries　compared　to　the　anti-solvent　process.　But　what　about　the　impact　of　unreacted　PbI2?　Usually,　it　is　generated　during　perovskite　conversion　in　a　two-step　method　and　considered　beneficial　within　the　grain　boundaries,　while　also　being　accused　of　enhancing　the　interface　defects　and　nonradiative　recombination.　Several　additives　are　mixed　in　PbI2　precursors　for　the　purpose　of　improving　the　perovskite　crystallinity　and　hindering　the　Pb2+　defects.　Herein,　in　lieu　of　adding　additives　to　the　PbI2,　the　effects　of　the　PbI2　residue　via　the　electron　transport　layer/perovskite　interface　modification　are　explored.　Consequently,　by　introducing　artemisinin　decorated　with　hydrophobic　alkyl　units　and　a　ketone　group,　it　reduces　the　residual　PbI2　and　improves　the　perovskites＇　crystallinity　by　coordinating　with　Pb2+.　In　addition,　artemisinin-deposited　perovskite　enhances　both　the　stability　and　efficiency　of　perovskite　solar　cells　by　suppressing　nonradiative　recombination