Large roomtemperature magnetocaloric effect with negligible magnetic hysteresis losses in Mn1−xVxCoGe alloys

► V-substitution for Mn reduces the structural transformation temperature of MnCoGe. ► FM-PM transition presents the second-order nature in Mn0.95V0.05CoGe. ► The first-order FM-PM transitions are observed for alloys with x=0.01, 0.02, and 0.03. ► Large room temperature MCEs are achieved in these alloys. ► Negligible magnetic HL is achieved for these alloys simultaneously.