Matseke, Mphoma SLuo, HongzeWen, LZheng, Haito2023-04-182023-04-182022-06Matseke, M.S., Luo, H., Wen, L. & Zheng, H. 2022. The upgraded performance of the NiFe2O4 /C electrocatalyst using Co substitution for the oxygen reduction reaction in an alkaline solution. <i>Journal of Physics and Chemistry of Solids, 165.</i> http://hdl.handle.net/10204/127550022-36971879-2553https://doi.org/10.1016/j.jpcs.2022.110644http://hdl.handle.net/10204/12755NiFe2O4 is one of the most abundant and inexpensive spinels; however, its activity toward the oxygen reduction reaction (ORR) is relatively low. For the first time, Co-substituted Fe partly of the NiFe2O4 electrocatalyst was studied to improve the intrinsic activity of ORR. Spinel-type NiFe2-xCoxO4/C electrocatalysts (x = 0, 0.25, 0.5 and 0.75) were synthesized by the hydrothermal method without further calcination. The well-crystallized NiFe2O4/C nanoparticles remained in a single phase after Co-substituting with sizes of 15–20 nm, characterized by TEM, SEM, XRD, and FTIR. XPS observes mixed valence states in the NiFe2-xCoxO4/C structure are observed, which has a beneficial effect on ORR. Furthermore, NiFe2-xCoxO4/C nanoparticles (x = 0.25, 0.5 and 0.75) show advanced ORR performance over NiFe2O4, particularly, the specific mass activity of NiFe1.75Co0.25O4/C is three times higher than that of NiFe2O4, also, with improved stability. After 4,000s, the NiFe1.75Co0.25O4/C electrocatalyst retained 84% of its initial current density, while the NiFe2O4/C electrocatalyst retained only 38%. The results revealed that Co substitutions have remarkably increased the intrinsic activity of the NiFe2O4 electrocatalyst for ORR by altering the structure, redistributing cations, and improving electrical conductivity.AbstractenCo-substituted FeNiFe2O4Oxygen reduction reactionORRSpinelArticleMatseke, M. S., Luo, H., Wen, L., & Zheng, H. (2022). The upgraded performance of the NiFe2O4 /C electrocatalyst using Co substitution for the oxygen reduction reaction in an alkaline solution. <i>Journal of Physics and Chemistry of Solids, 165</i>, http://hdl.handle.net/10204/12755Matseke, Mphoma S, Hongze Luo, L Wen, and Haito Zheng "The upgraded performance of the NiFe2O4 /C electrocatalyst using Co substitution for the oxygen reduction reaction in an alkaline solution." <i>Journal of Physics and Chemistry of Solids, 165</i> (2022) http://hdl.handle.net/10204/12755Matseke MS, Luo H, Wen L, Zheng H. The upgraded performance of the NiFe2O4 /C electrocatalyst using Co substitution for the oxygen reduction reaction in an alkaline solution. Journal of Physics and Chemistry of Solids, 165. 2022; http://hdl.handle.net/10204/12755.TY - Article AU - Matseke, Mphoma S AU - Luo, Hongze AU - Wen, L AU - Zheng, Haito AB - NiFe2O4 is one of the most abundant and inexpensive spinels; however, its activity toward the oxygen reduction reaction (ORR) is relatively low. For the first time, Co-substituted Fe partly of the NiFe2O4 electrocatalyst was studied to improve the intrinsic activity of ORR. Spinel-type NiFe2-xCoxO4/C electrocatalysts (x = 0, 0.25, 0.5 and 0.75) were synthesized by the hydrothermal method without further calcination. The well-crystallized NiFe2O4/C nanoparticles remained in a single phase after Co-substituting with sizes of 15–20 nm, characterized by TEM, SEM, XRD, and FTIR. XPS observes mixed valence states in the NiFe2-xCoxO4/C structure are observed, which has a beneficial effect on ORR. Furthermore, NiFe2-xCoxO4/C nanoparticles (x = 0.25, 0.5 and 0.75) show advanced ORR performance over NiFe2O4, particularly, the specific mass activity of NiFe1.75Co0.25O4/C is three times higher than that of NiFe2O4, also, with improved stability. After 4,000s, the NiFe1.75Co0.25O4/C electrocatalyst retained 84% of its initial current density, while the NiFe2O4/C electrocatalyst retained only 38%. The results revealed that Co substitutions have remarkably increased the intrinsic activity of the NiFe2O4 electrocatalyst for ORR by altering the structure, redistributing cations, and improving electrical conductivity. DA - 2022-06 DB - ResearchSpace DP - CSIR J1 - Journal of Physics and Chemistry of Solids, 165 KW - Co-substituted Fe KW - NiFe2O4 KW - Oxygen reduction reaction KW - ORR KW - Spinel LK - https://researchspace.csir.co.za PY - 2022 SM - 0022-3697 SM - 1879-2553 T1 - The upgraded performance of the NiFe2O4 /C electrocatalyst using Co substitution for the oxygen reduction reaction in an alkaline solution TI - The upgraded performance of the NiFe2O4 /C electrocatalyst using Co substitution for the oxygen reduction reaction in an alkaline solution UR - http://hdl.handle.net/10204/12755 ER -26453