Optimized bulk NiO catalyst in the oxidative dehydrogenation of ethane by tuning the synthesis parameters [Dataset]

Highly stable and selective bulk NiO catalysts have been synthesized for the oxidative dehydrogenation (ODH) of ethane to ethylene. Interestingly, by optimizing synthesis parameters such as the amount of oxalic acid in the synthesis gel and the calcination temperature, undoped NiO catalysts have shown a consistent selectivity to ethylene of ca. 75%. The optimal catalyst requires the presence of a certain amount of oxalic acid in the synthesis gel and a final calcination at low temperatures (i.e. 350 °C). These catalysts have been deeply characterized by means of XRD, TPR, HRTEM, Raman and UV–vis diffuse reflectance spectroscopies, XPS and Electrochemical Impedance Spectroscopy measurements and tested in the ethane ODH. A novel electrochemical study has been undertaken, showing the p-character of all the NiO catalysts synthesized but differing in their capacitance values and density of cationic vacancies. The catalytic performance of NiO catalysts has been explained in terms of the different physicochemical properties (including changes in the number of vacancies) of the samples and the isolation of electrophilic oxygen species. Description of methods used for collection/generation of data: X-ray diffraction patterns were collected in an Enraf Nonius FR590 diffractometer with a monochromatic CuKα1 source operated at 40 keV and 30 mA. The size of the NiO domains has been calculated through XRD technique by the Scherrer’ equation, D = k·λ/w·cosθ, where D is the crystallite size, k is a shape factor (0.9), λ is the X-ray wavelength (0.15406 nm), w is the full width at half maximum intensity (FWHM, in radians) and ϴ is the Bragg angle. MS tests were performed at a frequency of 5000 Hz in a 0.1 M Na2SO4 electrolyte. The potential was scanned from 1 VAg/AgCl in the negative direction using an amplitude signal of 0.01 V at 0.05 V/s. For this purpose, a three-electrode electrochemical cell was used. The catalyst was the working electrode (deposited on fluorine tin oxide (FTO)), a platinum tip the counter electrode and an Ag/AgCl (3 M KCl) the reference electrode. An area of 0.5 cm2 of the catalysts was exposed to the electrolyte. From EIS results, Mott-Schottky plots were carried out to evaluate the semiconductor behaviour of the catalysts and to determine their density of dopants. Methods for processing the data: Processed data are registered in files with extension csv.