Ni hydroxides (Ni(OH)2) are synthesized on Ni foam by varying the hexamethylenetetramine (HMT) concentration using an electrodeposition process for pseudocapacitor (PC) applications. In addition, the effects of HMT concentration on the Ni(OH)2 structure and the electrochemical properties of the PCs are investigated. HMT is the source of amine-based OH− in the solution; thus, the growth rate and morphological structure of Ni(OH)2 are influenced by HMT concentration. When Ni(OH)2 is electrodeposited at a constant voltage mode of -0.85 V vs. Ag/AgCl, the cathodic current and the number of nucleations are significantly reduced with increasing concentration of HMT from 0 to 10 mM. Therefore, Ni(OH)2 is sparsely formed on the Ni foam with increasing HMT concentration, showing a layered double-hydroxide structure. However, loosely packed Ni(OH)2 grains that are spread on Ni foam maintain a much greater surface area for reaction and result in the effective utilization of the electrode material due to the steric hindrance effect. It is suggested that the Ni(OH)2 electrodes with HMT concentration of 7.5 mM have the maximum specific capacitance (1023 F/g), which is attributed to the facile electrolyte penetration and fast proton exchange via optimized surface areas.

Abstract
 1. 서 론
 2. 실험방법
 3. 결과 및 고찰
 4. 결 론
 References

• 김동연(경북대학교 신소재공학부) | Dong Yeon Kim (Department of Materials Science and Metallurgical Engineering, Kyungpook National University)
• 정영민(대구경북과학기술원 스마트섬유융합연구실) | Young-Min Jeong (Smart Textile Convergence Research Group, DGIST)
• 백성호(대구경북과학기술원 스마트섬유융합연구실) | Seong-Ho Baek (Smart Textile Convergence Research Group, DGIST) Corresponding Authors
• 손인준(경북대학교 신소재공학부) | Injoon Son (Department of Materials Science and Metallurgical Engineering, Kyungpook National University) Corresponding Authors