(La,Sr)TiO₃ has been investigated as a promising anode material for solid oxide fuel cells (SOFCs) owing to its high electronic conductivity and superior phase stability. However, the low catalytic activity of (La,Sr)TiO₃ materials is a major obstacle to the application of SOFCs. Exsolution has emerged as an effective strategy to overcome the low catalytic activity of (La,Sr)TiO₃ materials. In this work, Ni-doped A-site-deficient La_0.4Sr_0.4TiO_3-δ (LST) (i.e., La_0.4Sr_0.4Ti_0.94Ni_0.06O_3-δ; LSTN) with in-situ exsolved Ni nanoparticles (NPs) was developed and the effects of exsolved Ni NPs on H₂ oxidation was investigated. The doped Ni was exsolved and formed NPs on the LSTN surface under reducing conditions. Owing to the high catalytic activity of the exsolved Ni NPs, the SOFC with LSTN-Ce_0.9Gd_0.1O_2-δ (GDC) yielded a maximum power density of 0.46 W cm⁻² at 850°C, 91% higher than that of the cell with LST-GDC, as well as high long-term and redox stability. Furthermore, density functional theory calculations revealed that the adsorption and dissociation of H₂ were more favorable for exsolved Ni NPs than for pure Ni owing to the more positively charged surface of the exsolved Ni NPs in the LSTN. These results demonstrated that exsolution is an effective method for improving the electrocatalytic activity of perovskite (La,Sr)TiO₃ materials.

(La,Sr)TiO ₃因其高电子电导率和优异的相稳定性而被研究为一种有前途的固体氧化物燃料电池（SOFC）阳极材料。然而，(La,Sr)TiO ₃材料的低催化活性是SOFCs应用的主要障碍。脱溶已成为克服 (La,Sr)TiO ₃材料催化活性低的有效策略。在这项工作中，Ni 掺杂的 A 位缺陷 La _0.4 Sr _0.4 TiO _3-δ (LST)（即 La _0.4 Sr _0.4 Ti _0.94 Ni _0.06 O _3-δ ; LSTN）与原位开发了外溶的 Ni 纳米粒子 (NPs)，并研究了外溶的 Ni NPs 对 H ₂氧化的影响。在还原条件下，掺杂的 Ni 在 LSTN 表面上被溶解并形成 NPs。由于外溶 Ni NPs 的高催化活性，具有 LSTN-Ce _0.9 Gd _0.1 O _2-δ (GDC)的 SOFC在 850°C 下产生的最大功率密度为 0.46 W cm ^-2，比具有 LST-GDC 的电池，以及高长期和氧化还原稳定性。此外，密度泛函理论计算表明，H ₂的吸附和解离由于 LSTN 中析出的 Ni NPs 的表面带正电，因此对析出的 Ni NPs 比纯 Ni 更有利。这些结果表明，外溶是提高钙钛矿(La,Sr)TiO ₃材料电催化活性的有效方法。