La₂Zr_1.44Ni_0.56O_7-d (LNZ6), La_1.95Ca_0.05Zr_1.44Ni_0.56O_7-d (LCNZ6), La_1.95Sr_0.05Zr_1.44Ni_0.56O_7-d (LSNZ6) catalysts were investigated for DRM reaction to determine the effect of Sr- and Ca- substitution at the La site in Ni substituted Lanthanum Zirconate pyrochlore. XRD confirmed the formation of the pyrochlore phase with Ni substitution. Additionally, NiO and perovskite phases of Ni were detected. XANES and XRD confirmed the reduction of Ni to active Ni⁰ phase in reduced and spent catalysts. LSNZ6 turned out to be the most active DRM catalyst because of the higher surface Ni content, smaller particle size and high dispersion achieved as observed from XPS, XRD, SEM-EDS elemental mapping and TPR. LSNZ6 exhibited better resistance to sintering with negligible Ni size growth compared to LCNZ6 and LNZ6. Coke formation was inevitable and LSNZ6 showed more carbon formation which suggests carbon deposition correlated directly with activity. However, it had negligible impact on the activity and stability of the catalysts.

研究了La ₂ Zr _1.44 Ni _0.56 O _7-d（LNZ6），La _1.95 Ca _0.05 Zr _1.44 Ni _0.56 O _7-d（LCNZ6），La _1.95 Sr _0.05 Zr _1.44 Ni _0.56 O _7-d（LSNZ6）催化剂反应确定在镍取代的锆酸锆烧绿石中镧位点上Sr和Ca取代的影响。XRD证实了被Ni取代的烧绿石相的形成。另外，检测到NiO和Ni的钙钛矿相。XANES和XRD证实Ni还原为活性Ni ⁰还原和废催化剂中的相。LSNZ6被证明是最具活性的DRM催化剂，因为从XPS，XRD，SEM-EDS元素图谱和TPR观察到，表面镍含量更高，粒径更小，分散度更高。与LCNZ6和LNZ6相比，LSNZ6表现出更好的抗烧结性，且Ni尺寸增长可忽略不计。焦炭的形成是不可避免的，并且LSNZ6显示出更多的碳形成，这表明碳沉积与活性直接相关。但是，它对催化剂的活性和稳定性的影响可忽略不计。