Kang Wenli, Li Zhishan, Wang Jinsong, Wu Shaopeng, Gai Yiguang, Wang Guanghao, Li Zhouhang, Zhu Xing, Zhu Tao, Wang Hua, Li Kongzhai, Wang Chundong
Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093, PR China.
Faculty of Materials Science and Engineering, Kunming University of Science and Technology, Kunming 650093, PR China.
Nanoscale. 2024 Jan 25;16(4):1823-1832. doi: 10.1039/d3nr05259a.
Here, a series of transition metal (Ni) doped iron-based perovskite oxides LaFeNiO ( = 0, 0.25, 0.5, 0.75, 1) were prepared, and then the perovskite oxide with the optimized nickel-iron ratio was doped with non-metallic elements (N). Experimental and theoretical investigations reveal that the co-doping breaks the traditional linear constraint relationship ( - = 3.2 eV) and the theoretical overvoltage is reduced from 0.64 V (LaFeO) to 0.44 V (LaFeNiO/N). Specifically, Ni-doping can accelerate electron transfer and improve the conductivity. Moreover, N-doping can reduce the adsorption energy of *OH/*O and enhance the adsorption energy of *OOH. We demonstrated that the optimized cation and anion co-doped LaFeNiO/N perovskite oxide exhibits an excellent OER performance, with a low overpotential of 270.6 mV at 10 mA cm and a small Tafel slope of 65 mV dec in 1 M KOH solution, markedly exceeding that of the parent perovskite oxide LaFeO (300.9 mV) and commercial IrO (289.1 mV). It also delivers decent durability with no significant degradation after a 35 h stability test. This work reveals the internal mechanism of perovskite oxide by doping cation and anion for water oxidation, which broadens the idea for the rational design of new perovskite-based sustainable energy catalysts.
在此，制备了一系列过渡金属（Ni）掺杂的铁基钙钛矿氧化物LaFeNiO（ = 0、0.25、0.5、0.75、1），然后将具有优化镍铁比的钙钛矿氧化物用非金属元素（N）进行掺杂。实验和理论研究表明，共掺杂打破了传统的线性约束关系（ - = 3.2 eV），理论过电位从0.64 V（LaFeO）降至0.44 V（LaFeNiO/N）。具体而言，Ni掺杂可加速电子转移并提高导电性。此外，N掺杂可降低*OH/O的吸附能并增强OOH的吸附能。我们证明，优化后的阳离子和阴离子共掺杂的LaFeNiO/N钙钛矿氧化物表现出优异的析氧反应性能，在1 M KOH溶液中，在10 mA cm时过电位低至270.6 mV，塔菲尔斜率小至65 mV dec，明显超过母体钙钛矿氧化物LaFeO（300.9 mV）和商业IrO（289.1 mV）。在35小时稳定性测试后，它还具有良好的耐久性，无明显降解。这项工作揭示了通过阳离子和阴离子掺杂钙钛矿氧化物用于水氧化的内在机制，拓宽了合理设计新型钙钛矿基可持续能源催化剂的思路。
