In　recent　years,　colloidal　quantum　dots　(CQDs)　have　been　widely　used　in　optoelectronic　devices　due　to　their　advantages　including　low　cost,　solution　processability,　substrate　compatibility,　and　easily　tuned　photoelectric　characteristicsviathe　quantum　size　effect.　However,　there　are　several　factors　still　limiting　the　further　improvement　of　performances　for　CQD　optoelectronic　devices:　(1)　the　incomplete　surface　passivation　of　CQDs;　(2)　a　trade-off　between　absorption　and　photogenerated　carrier　collection;　and　(3)　the　poor　air　stability.　This　review　focuses　on　the　methods　for　performance　improvement　of　CQD-based　photoelectric　conversion　devices　including　photovoltaic　solar　cells　and　photodetectors.　Taking　CQD　solar　cells　as　an　example,　different　surface　passivation　methods　are　summarized.　To　increase　the　separation　and　collection　of　photogenerated　carriers,　the　device　architecture　is　optimized　by　aligning　the　energy　band　and　broadening　the　depletion　width.　Additionally,　device　performance　can　be　further　enhanced　through　interface　modification　which　could　decrease　recombination.　In　the　next　section,　recent　progress　in　the　development　of　CQD　near-infrared　(NIR),　short-wave　infrared　(SWIR),　and　mid-wave　infrared　(MWIR)　photodetectors　is　reviewed.　To　overcome　the　traditional　photodetection　limitations　posed　by　the　dark　current/sensitivity/bandwidth　trade-off,　innovative　device　architectures　are　developed.　Finally,　this　review　discusses　the　application　of　CQD　photodetectors　in　infrared　imaging.　©　The　Royal　Society　of　Chemistry　2021.