No abstract

Dry reforming of methane (DRM) over an Ni-based catalyst is an innovative research area due to the growing environmental awareness about mitigating global warming gases (CH4 and CO2) and creating a greener route of synthesis. Herein, 5% Ni supported on ZrO2 obtained from various sources was prepared by the impregnation method. The catalysts were calcined at 600, 700, and 800 °C. Furthermore, Ni-RC stabilized with MgO, SiO2, TiO2, and Y2O3 were tested. Characterization techniques employed comprise the N2 physisorption, infrared spectroscopy, Raman, thermogravimetric analysis, XRD, and TEM. The results of the present study indicated that the ZrO2 support source had a profound effect on the overall performance of the process. The best catalyst Ni-RC gave an average conversion of CH4 and CO2 of 61.5% and 63.6% and the least deactivation of 10.3%. The calcination pretreatment differently influenced the catalyst performance. When the average methane conversion was higher than 40%, increasing the calcination temperature decreased the activity. While for the low activity catalysts with an average methane conversion of less than 40% the impact of the calcination temperature did not constantly decrease with the temperature rise. The stabilization of Ni-RC denoted the preference Y2O3 stabilized catalyst with average values of CH4 and CO2 conversion of about 67% and 72%, respectively. The thorough study and fine correlation will be advantageous for technologically suitable Ni-15Y-RC catalysts for DRM.

No abstract

No abstract

We used theoretical and computational methods to explore the double perovskites Cs 2 YInX 6 (X = Cl, Br, I) by having the scope and goal of finding their physical aspects and characteristic. To properly explain different phenomenological features of density functional theory (DFT), the ab-initio computational model based on the approximation of full-potential augmented plane wave plus local orbitals (FP-LAPW + lo) technique was implemented. The calculated ground state properties with GGA-PBEsol agree well with the available other theoretical data. Mechanical properties, another very important aspect of these double perovskites, are found by using shear modulus, Young's modulus, and Poisson's ratio. Further, we obtained bandgaps by investigating electronic properties with and without spin-orbit coupling (SOC). In order to calculate and compare the bandgaps with experimental results, we used SOC in connection with mBJ potential to investigate the direct bandgaps of Cs 2 YInCl 6 (E g = 0.45 eV), Cs 2 YInBr 6 (E g = 0.65 eV) and Cs 2 YInI 6 (E g = 0.82 eV) respectively. Furthermore, optical properties are investigated in terms of calculations like complex dielectric constants (ε(ω)), refractive index (n(ω)), reflectivity (R(ω)) and absorption co-efficient (α(ω)) to find their possible applications in optoelectronic devices. In view of this background, BoltzTraP code will also be used to explore these double perovskites in respect of their thermoelectric applications.