In the present manuscript, we address the effects of B-site substitution (Fe and Co) on the redox performance of CaMnO3, under the conditions of chemical looping combustion (CLC). The variations in composition and redox chemistry were found to be influenced by both the nature and the amount of the B-site components and the temperature of operation. The low-temperature (600 degrees C) performance was found to be enhanced by replacing Mn with 5% of Fe or Co, independently. At 750 degrees C, all of the materials were found to exhibit performance loss during the first few cycles. Even though these materials exhibited stable reduction and re-oxidation extents afterward, complete destruction of the perovskite structure was observed after 15 cycles. At 900 degrees C, the long-term redox performance variations were found to not depend on the presence of impurity phases and surface structure, indicating that the oxidation state of the cations and temperature were playing a more decisive role in determining the redox chemistry of these materials. All of the materials used in this study were found to selectively suppress the undesirable CH4 splitting reaction and the resultant carbon deposition, which may be attributed to the basicity of Ca.