The relationship among the bulk structure, Ni/Co reduction, site formation, and the catalytic performance of Ni-Co-Al-Mg-O composite synthesized by co-precipitation method was studied for CO₂ reforming of CH₄ (DRM). Three catalysts were prepared by changing the Mg/Al ratio of the composite from 0.3 to 2. The catalysts were denoted as CopCat-Mg/Al-0.3, CopCat-Mg/Al-1, and CopCat-Mg/Al-2. ICP-MS, XRD, Al-NMR, XPS, TEM, and XANES (Mg, Al, Ni/Co K-edge) were utilized to characterize the crystalline structure, the coordination number, degree of spinel inversion, and the Ni /Co reduction of the catalysts. Results showed that the bulk structure of the calcined precipitates changed from spinel-dominating to the co-existence of spinel and MgO solid solution phases as the Mg/Al ratio changed from 0.3 to 2. In the spinel-dominating structures, Ni and Co reduction was found to be difficult, and a small number of metallic sites with larger nanoparticles were generated after reduction. As the MgO solid-phase became significant, the reduction of Ni and Co was enhanced, and more metallic sites of smaller sizes were formed. These metallic sites performed differently for the activation of CH₄ and CO₂, as the catalyst with the lowest Mg/Al ratio (<0.5) experienced carbon deposition and produced synthetic gas of low H₂/CO ratio, which led to lower catalytic activity and quicker catalyst deactivation during DRM. In contrast, the catalyst with the highest ratio of Mg/Al suppressed carbon formation, maintained a higher catalytic activity and stability due to the improved basicity that promoted the quick conversion of carbon to CO.

研究了共沉淀法合成的Ni-Co-Al-Mg-O复合材料的整体结构，Ni / Co还原，位点形成以及催化性能与CH _4的CO ₂重整之间的关系。（DRM）。通过将复合物的Mg / Al比从0.3改变为2来制备三种催化剂。将催化剂表示为CopCat-Mg / Al-0.3，CopCat-Mg / Al-1和CopCat-Mg / Al-2。利用ICP-MS，XRD，Al-NMR，XPS，TEM和XANES（Mg，Al，Ni / Co K-edge）表征晶体结构，配位数，尖晶石反转度和Ni / Co还原催化剂。结果表明，随着Mg / Al的比值从0.3变为2，煅烧析出物的整体结构从尖晶石为主转变为尖晶石和MgO固溶体相共存。在尖晶石主导结构中，Ni和Co还原发现是困难的，并且还原后产生少量具有较大纳米颗粒的金属位点。随着MgO固相的增加，Ni和Co的还原作用增强，并形成了更多的小尺寸金属部位。这些金属位点对CH的活化作用不同_如图4和图_4所示，作为具有最低Mg / Al比（＜0.5）的催化剂，碳沉积并产生低H ₂ / CO比的合成气，这导致较低的催化活性和在DRM期间更快的催化剂失活。相反，Mg / Al比例最高的催化剂抑制了碳的形成，由于碱度提高，促进了碳向CO的快速转化，因此保持了较高的催化活性和稳定性。