ELECTROCATALYSTS BASED ON Ni-, Co-SPINELS
Journal Title: Вісник Одеського національного університету. Хімія - Year 2016, Vol 21, Issue 2
Abstract
The synthesis of Ni-, Co-spinels was performed using coprecipitation method with precursors Ni and Co nitrates under different conditions: using precipitators NaOH and NH4OH, at different pH values and different aging durations. Structural, adsorption and catalytic properties by of Ni-, Co-spinels were determined by X-ray diffraction, desiccator method of adsorption of benzene vapor and in redox reaction of hydrogen peroxide decomposition. The size of the crystallites of obtained spinels was calculated from X-ray diffraction patterns and all of the samples were nano-dispersed with developed surface area from 92 to 320 m2/g. Electrocatalytic investigations have shown that the most active spinels were obtained by precipitation with NH4OH at pH 9,0. The highest catalytic activity from all of the twelve spinels samples in hydrogen peroxide decomposition reaction had Ni-, Co-spinel, precipitated by NH4OH at pH 9,0 and aged for 3 days which shown 100% decomposition degree of H2O2 after 45 seconds of contact. According to the results, the conditions of synthesis of Ni-, Co-spinels highly effect on their catalytic activity. Significantly lower catalytic activity of samples precipitated by NaOH, in our opinion, explained by the inhibitory effect of sodium, which is formed by the heat treatment of samples containing NaOH in trace amounts. Established that with decreasing pH values to neutral the activity of Ni-, Co-spinels increases and with increasing duration of aging of samples their catalytic activity is reduced due to the recrystallization process sediment, resulting in the number of active sites on the surface of Ni-, Co-spinels decreases.
Authors and Affiliations
K. A. Fedoruk, I. N. Ivanenko, I. M. Astrelin, А. P. Burmak
Keywords
Related Articles
- EP ID EP337102
- DOI 10.18524/2304-0947.2016.2(58).74789
- Views 90
- Downloads 0
ISOTHERMAL SECTION OF THE Al2O3–TiO2–Yb2O3 PHASE DIAGRAM AT 1400 °С
One of the main directions of the modern materials development science is the development of new oxide ceramic materials for engineering, energy, chemical, aerospace, electronic and other industries in multi component sy...
PECULIARITIES OF ACID-BASIC PROPERTIES OF SILICON AND GERMANIUM OXY-COMPOUNDS
Peculiarities of the change of acid-basic properties of Silicon and Germanium oxy-compounds as a function of the position of elements in the periodic system are established. It is stated that Germanium dioxide possesses...
SPECTROSCOPIC STUDY OF INTERACTION OF INDOMETHACIN AND DACLATASVIR DIGIDROCHLORIDE WITH HUMAN SERUM ALBUMIN
Fluorescence spectroscopy is one of the most effective methods for studying the binding of drugs to proteins, which is important for the purposes of biochemistry and medicine. When studying the interaction in vitro, huma...
DETERMINATION OF RIVASTIGMINE HYDROTARTRATE RESIDUES ON PHARMACEUTICAL MANUFACTURING EQUIPMENT SURFACES BY HPLC AND LUMINESCENCE METHODS
Highly sensitive HPLC methods of determination of rivastigmine hydrotartrate trace amounts for cleaning of the pharmaceutical equipment have been proposed. The developed methods have been validated on the following param...
LONG-TERM DYNAMICS FLUORINE CONTENT IN THE SURFACE WATERS OF THE BASIN KUYALNIK ESTUARY
This article summarizes the original results of a study of fluorine levels in the water of Kuyalnik estuary and its watercourses for the period 2005-2013. We estimated dynamics of annual and seasonal changes of the fluor...