Remarkable Enhancement of Electrochemical Performance by the Oxygen Vacancy and Nitrogen Doping in ZnCo 2 O 4 Nanowire Arrays

In Kyu Moon, Seonno Yoon, Bugeun Ki, Kerock Choi, Jungwoo Oh

Research output: Contribution to journalArticle

2 Citations (Scopus)


To improve overall electrochemical performance, we report and propose zinc cobaltite (ZnCo 2 O 4 ) nanowire arrays with a simple and precisely controllable NH 3 plasma treatment. The NH 3 plasma treatment effectively changes the electronic and chemical properties of the pristine ZnCo 2 O 4 by the nitrogen doping and surface functionalization simultaneously. By way of the nanoscale surface/electrical modification of ZnCo 2 O 4 , the nitrogen (N)-doped ZnCo 2 O 4 electrodes not only significantly enhanced the electrical conductivity but also increased the density of the hydroxyl group by appropriately controlling the Co 2+ /Co 3+ ratio (oxygen vacancies). Compared to pristine ZnCo 2 O 4 (1682.2 F g -1 at 5 A g -1 ), the N-doped ZnCo 2 O 4 electrode without conductive additives possessed high specific capacitance (3804.6 F g -1 at 5 A g -1 ), excellent rate capability (95.45% capacity retention at 40 A g -1 ), and good cycling stability (only 3.3% loss after 3000 cycles at 30 A g -1 ). These nanoscale surface state engineering methods may open a new avenue to optimize electrochemical performance for energy storage and conversion.

Original languageEnglish
Pages (from-to)4804-4813
Number of pages10
JournalACS Applied Energy Materials
Issue number9
Publication statusPublished - 2018 Sep 24


All Science Journal Classification (ASJC) codes

  • Energy Engineering and Power Technology
  • Chemical Engineering (miscellaneous)
  • Electrochemistry
  • Materials Chemistry
  • Electrical and Electronic Engineering

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