Large　pyroelectric　and　energy　harvesting　properties　have　been　attracting　increasing　attentions　due　to　the　practical　applications　in　infrared　detectors　and　energy　harvesting　technologies.　Ferroelectric-antiferroelectric　(FE-AFE)　phase　transitions　are　usually　accompanied　by　a　sharp　drop　in　polarization,　which　will　lead　to　excellent　pyroelectric　properties　and　energy　harvesting　density.　Therefore,　FE-AFE　phase　boundary　design　is　an　effective　strategy　to　develop　new　pyroelectric　materials.　In　this　paper,　Pb(Lu1/2Nb1/2)O3-PbTiO3　(PLN-PT)　single　crystals　with　FE-AFE　phase　transitions　were　obtained　by　molten　salt　growth　method.　The　temperature-induced　FE-AFE　phase　transition　was　verified　by　temperature-dependent　macrodomain　structure,　DSC　curves　and　dielectric　properties.　Obviously,　PLN-PT　crystals　display　excellent　peak　pyroelectric　coefficient　(∼6.8　μC/(cm2·K))　with　a　maximum　depolarization　temperature　of　118　°C.　Meanwhile,　the　pyroelectric　energy　harvesting　density　is　as　high　as　2.62　J/cm3,　which　is　much　higher　than　other　pyroelectric　materials.　The　results　reveal　that　the　PLN-PT　crystal　is　a　promising　candidate　for　infrared　detectors　and　energy　harvesting　devices.　©　2021