Chen Yang, Tong Zheng, Zhiyuan Li, Fangyong Yu, Haibin Sun, Femiana Gapsari, Jaka Sunarso
In an effort to obtain simultaneous enhancement in the electrochemical performance and the electronic conductivity while achieving resistance to chromium (Cr) poisoning, here we developed high-entropy perovskite oxide with the composition of (La0.2Nd0.2Sm0.2Sr0.2Ba0.2)0.95(Co0.2Fe0.8)1-xNixO3-δ (HE-LSCF095Nix, x = 0.05, 0.10, 0.15), which contains A-site deficiency and different amount of Ni doping. The composition that contains 0.10 Ni doping, i.e., HE-LSCF095Ni10 showed the highest electrochemical performance, i.e., the lowest polarization resistances (Rp) of 0.83 Ω cm2 at 650 °C and 0.39 Ω cm2 at 700 °C, which are much lower than those of its original high entropy parent perovskite analog La0.2Nd0.2Sm0.2Sr0.2Ba0.2Co0.2Fe0.8O3-δ (HE-LSCF) of 2.14 Ω cm2 at 650 °C and 0.60 Ω cm2 at 700 °C. Density functional theory (DFT) calculations and electrical conductivity measurements revealed that the higher electrochemical performance for HE-LSCF095Ni10 relative to HE-LSCF is due to the lower oxygen vacancy formation energy (−52.75 eV < −19.78 eV) and work function (5.682 eV < 7.301–7.807 eV) and the higher electronic conductivity for the former (193.82 S cm−1 > 168.15 S cm−1 at 700 °C). Notably, following Cr treatment for 40 h, HE-LSCF095Ni10-based symmetrical cell displayed marginal increase in Rp, indicating good resistance to Cr poisoning. Anode-supported single cell based on HE-LSCF095Ni10, i.e., NiO-SDC|SDC|HE-LSCF095Ni10 showed relatively high peak power densities of 0.639, 0.806, and 0.939 W cm−2 at 650, 700, and 750 °C, respectively, which are comparable to the other cells based on best performing cathodes. © 2025 Elsevier Ltd and Techna Group S.r.l.
School of Materials Science and Engineering, Shandong University of Technology, Shandong, Zibo, 255000, China; School of Chemistry and Chemical Engineering, Shandong University of Technology, Shandong, Zibo, 255000, China; Department of Mechanical Engineering, Faculty of Engineering, Brawijaya University, MT Haryono 167, Malang, 65145, Indonesia; Research Centre for Sustainable Technologies, Faculty of Engineering, Computing and Science, Swinburne University of Technology, Jalan Simpang Tiga, Sarawak, Kuching, 93350, Malaysia
