Magnetocaloric effect of ball-milled CoMn0.95V0.05Ge nano-powders

•CoMn0.95V0.05Ge nano-powders prepared by ball milling of bulk alloy.•The magnetic transition for nano-powders is second order in nature, although their bulk counterpart with same composition exhibits a first order magnetostructural phase transition.•The isothermal magnetization of the nanoparticles shows almost no hysteresis behavior.•Relative cooling power value shows that CoMn0.95V0.05Ge nano-powders are competitive magnetocaloric materials.