Influence of the carbonate ion on characteristics of electrochemically synthesized layered (α+β) nickel hydroxide

Abstract

Nickel hydroxide is widely used as the active material of supercapacitors. The most active are samples of Ni(OH)<sub>2</sub> with (α+β) layered structure, synthesized in the slit diaphragm electrolyzer. Influence of carbonate anion on the structure and electrochemical properties of nickel hydroxide samples has been studied by means of sample synthesis in the slit-diaphragm electrolyzer with the use of the diaphragm and cation-exchange membrane as chamber separator. The experiment revealed that when the diaphragm is used, there is a filtration flow from the anodic chamber (alkali with carbonate) into the cathodic chamber. Thus, the samples synthesized with the diaphragm are formed in the presence of carbonates, while the samples synthesized with the cation-exchange membrane – in the absence of carbonates. Crystal structure of the samples was studied by means of X-ray diffraction analysis, electrochemical characteristics – by means of cyclic voltammetry and galvanostatic charge-discharge cycling in the accumulator regime. Comparative analysis of the samples synthesized in the presence or absence of carbonates has been conducted. By means of X-ray diffraction and cyclic voltammetry, the key role of carbonate ions in the formation of monophase layered (α+β) structure has been revealed. The absence of carbonate resulted in lower crystallinity, α-phase content, the formation of the bi-phase system, composed of the mixture of β-form and (α+β)-structure, at high current densities (12 and 15.7 A/dm<sup>2</sup>). The study of electrochemical characteristics revealed a decrease in specific capacity by 14.7–31.4 % for hydroxide samples formed in the absence of carbonate ions. The highest specific capacity was obtained for the samples synthesized in the SDE at i=10 A/dm<sup>2</sup> with the diaphragm (in the presence of carbonates) and with the membrane (in the absence of carbonates), and are 216.8 and 185 mA·h/g respectively. To increase specific capacity, it is recommended to conduct synthesis in the SDE with the use of the diaphragm and introduce an additional quantity of sodium carbonate into the anolyte

Authors and Affiliations

Vadym Kovalenko, Valerii Kotok

Keywords

Related Articles

Substantiation of the development of formulations for organic cupcakes with an elevated protein content

<p class="a">In order to develop the formulations for organic cupcakes with an elevated protein content, we examined and analyzed the amino acid composition of four samples of flour: wheat flour, organic wheat flour, org...

Development of fatigue test technology of sheet automobile materials

<p>Ensuring the operability of the cars’ parts and components is one of the most topical problems in the modern automotive industry. Most of the car parts are under cyclic loads leading to materials’ destruction. Therefo...

Web­oriented decision support system for planning agreements execution

<p class="a">The problem of construction of the web-based decision support system when planning the execution of agreements at service-rendering enterprises is considered. Characteristics of operations of such enterprise...

Development of methodical provisions regarding the substantiation of the combat structure of forces for activities in the airspace

<p>The determining factor for success during modern warfare is the struggle for supremacy in the air. The main task for a defending side is to prevent the enemy's superiority in the air. Various means of destruction are...

Development of a method of increasing the interference immunity of frequency-hopping spread spectrum radio communication devices

The development of a technique for increasing the interference immunity of frequency-hopping spread spectrum radio communication equipment has been carried out. The essence of the proposed method is the rational distribu...

Download PDF file
  • EP ID EP666198
  • DOI 10.15587/1729-4061.2019.155738
  • Views 60
  • Downloads 0

How To Cite

Vadym Kovalenko, Valerii Kotok (2019). Influence of the carbonate ion on characteristics of electrochemically synthesized layered (α+β) nickel hydroxide. Восточно-Европейский журнал передовых технологий, 1(6), 40-46. https://europub.co.uk/articles/-A-666198