Engineering Dysprosium-Nickel Co-Doped Alumina Catalysts: Correlating Thermal Stability, Morphology, and Surface Chemistry through Advanced Characterization Techniques

<jats:p>The development of thermally stable and highly dispersed catalyst systems is essential for advanced catalytic applications involving carbon dioxide conversion and related heterogeneous reactions. In the present study, a novel rare-earth-metal-promoted alumina catalyst co-doped with dysprosium (Dy) and nickel (Ni) was synthesized and systematically investigated to evaluate its structural, morphological, and thermal properties. The catalyst was prepared by incorporating varying concentrations of dysprosium onto an alumina support followed by nickel modification, resulting in a multifunctional catalytic framework with enhanced physicochemical characteristics. Comprehensive characterization techniques including Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDX), elemental mapping, Fourier Transform Infrared Spectroscopy (FTIR), X-ray Photoelectron Spectroscopy (XPS), and Thermogravimetric Analysis (TGA/DTA) were employed to assess surface morphology, elemental distribution, chemical bonding, oxidation states, and thermal stability of the synthesized materials. SEM micrographs revealed significant modifications in surface texture and particle agglomeration behavior with increasing dysprosium loading, while EDX and elemental mapping confirmed the homogeneous distribution of Dy and Ni species across the alumina matrix. FTIR and XPS analyses demonstrated successful incorporation of rare-earth and transition-metal species, leading to the formation of strong metal-support interactions and modified surface functionalities. Thermogravimetric studies indicated excellent thermal resistance of the co-doped catalyst over a wide temperature range, exhibiting limited mass loss and enhanced structural integrity during thermal degradation. Kinetic analysis derived from TGA data showed progressive increases in reaction rate constants with temperature, confirming favorable thermal behavior and stability of the catalyst system. The synergistic interaction between dysprosium, nickel, and alumina contributed to improved thermal robustness, surface uniformity, and physicochemical stability compared to 2 conventional alumina-supported catalysts. The findings demonstrate that Dy-Ni co-doped alumina catalysts possess promising characteristics for high-temperature catalytic processes and carbon dioxide utilization technologies. This work provides valuable insights into the design of rare-earth-modified catalyst systems and establishes a foundation for their future application in sustainable catalytic conversion and environmental remediation processes.</jats:p>