Active and durable alkaline earth metal substituted perovskite catalysts for dry reforming of methane

•MZr0.8Ni0.2O3-δ (M=Ca, Sr and Ba) perovskite catalysts were prepared by citrate gel method.•Nature of alkaline earth at ‘A’ site of perovskite influences the performance of the catalysts.•CaZr0.8Ni0.2O3-δ has higher oxygen defect sites and stronger metal support interaction.•Surface hydroxyl groups on CaZr0.8Ni0.2O3-δ help to control the coke formation.•CaZr0.8Ni0.2O3-δ is highly active and also stable even after 500h of reaction.