Inhibition of sintering and coking by post-coating group IIA metal oxides on trace-Rh-promoted Ni-based catalysts for high-temperature steam reforming

•Post-coating of alkaline earth metal oxides is effective for sintering-resistance.•MgO–Rh–Ni–CZO showed negligible Ni sintering and carbon desposition for 50-h test.•Superior performance is originated from reduction inhibition and Mg–O–Ni formation.•MgO pre-coating cannot obtain promising stability as post-coated method.