La0.97Yb0.03CoO3 perovskite with excellent CO2 and H2O resistance for total oxidation of propane

In this study, La 1−x Yb x CoO 3 (x = 0, 0.01, 0.03, 0.05) perovskite oxides were synthesized by a sol–gel route. The obtained materials were characterized by XRD , BET, H 2 -TPR, O 2 -TPD, SEM , TGA , XPS , and evaluated in the catalytic oxidation of propane. It is demonstrated that the suitable introduction of Yb in A site of LaCoO 3 perovskite can create structural defects promoting reducibility of Co ions , increasing Co 2+ /Co 3+ ratios and O ads /O latt ratio. When Yb is excessive, a cubic perovskite phase with decreased defects is found. As a result, La 0.97 Yb 0.03 CoO 3 catalyst shows the highest of reaction rate 1.15 μmol C3H8 /(g·s) at 350 °C, when it is 0.76 μmol C3H8 /(g·s) for pristine LaCoO 3 . Moreover, it exhibits excellent stability in a duration test of 80 h at 400 °C and strong resistance against 5 vol% H 2 O and/or 5 vol% CO 2 during a lasting 40 h. The effective oxidation of propane was realized by using La 0.97 Yb 0.03 CoO 3 perovskite catalysts with abundant Co 3+ and defects. • The La 1−x Yb x CoO 3 perovskites were synthesized by a facile sol-gel route. • The correlations among O ads /O latt ratio, Co 2+ /Co 3+ and catalytic performance were studied. • The La 1−x Yb x CoO 3 display excellence oxidation performance and H 2 O/CO 2 resistance. • In-situ FTIR confirms the C 3 H 8 evolution: CH 3 CH 2 CH 3 .→CH 2 CHCH 3 →CH 2 CHCH 2 OH→CH 2 CHCOOH→CO 2 .