Mitigation on self-discharge behaviors via morphological control of hierarchical Ni-sulfides/Ni-oxides electrodes for long-life-supercapacitors  

作　　者：Dhananjay Mishra Niraj Kumar Ajit Kumar SeungGi Seo SungHun Jin 

机构地区：[1]Department of Electronic Engineering,Incheon National University,Incheon 406-772 and also with Convergence Research Center for Insect Vectors,Incheon National University,Republic of Korea

出　　处：《Journal of Materials Science & Technology》2022年第18期217-228,共12页材料科学技术（英文版）

基　　金：supported by the National Research Founda-tion of Korea(NRF)funded by the Ministry of Science,ICT and Fu-ture Planning(NRF-2021R1A2C1012593);in part by the Prior-ity Research Centers Program through the National Research Foun-dation of Korea(NRF)funded by the Ministry of Education(NRF-2020R1A6A1A03041954).

摘　　要：To cope up with the sustainable energy storage goals for supercapacitors(SCs),the self-discharge in SC electrodes is a significant hurdle,and thereby,nickel sulfide(NS)with high conductivity is adopted as a test vehicle for understanding the morphological evolution effects for long-life SCs.Herein,honeycomb-like NS is hierarchically formed over hydrothermally grown nickel oxide(NO)via successive ionic layer adsorption reaction(SILAR)method.Their heterostructure shows a fivefold improvement in specific capacitance from 348 F g^(−1) to 2077 F g^(−1)at 1 mV s^(−1) over bare NO.Furthermore,the remarkable upliftment of capacitance retention is achieved from 60.7%to 92.3%even after 3000 cycles via morphological control of NS/NO hetero-structure with the help of highly conductive NS.More importantly,the self-discharge behaviors and synergistic role of leakage current associated with morphological evolution via NS overcoating are studied in detail.In particular,the self-discharge mitigation from 45%(NO)to 35%(NS20/NO)due to the NS/NO heterostructure and the behind mechanism are ascribed to the activated-controlled Faradaic reaction coupled with a charge redistribution.This study emphasizes the potential importance of composite heterostructure by tuning the electrical conductivity and morphological adjustment NO via consecutive overcoating of NS through SILAR as a novel strategy.This enhances charge storage,redox kinetics,and the mitigation of self-discharge properties of the active electrode materials.For practical validation on sustainable energy storage,NS20/NO supercapacitors illuminate the LED for 35%longer than NO after one-time charging,potentially beneficial for the next generation SCs.

关 键 词：Morphological evolution SELF-DISCHARGE SILAR overcoating SUPERCAPACITORS HETEROSTRUCTURE 

分 类 号：TM53[电气工程—电器] TQ138.13[化学工程—无机化工]