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2026 Vol.36, Issue 3 Preview Page

Research Paper

Effect of Processing Gas Atmosphere on Electrochromic Performances of Amorphous WO3･H2O Films formed at Low Temperature

저온에서 형성된 비정질 WO3･H2O 막의 가스 분위기에 따른 전기변색 성능 영향

Seong-Hoon Kang1
,
Ji Yong Jung1
,
Bon-Ryul Koo1†
강 성훈1
,
정 지용1
,
구 본율1†
1Department of Advanced Materials and Biochemical Engineering, Kangwon National University, Gangneung 25457, Republic of Korea
1강원대학교 신소재생명화학공학부 세라믹신소재공학전공
†Corresponding author E-Mail : brkoo@kangwon.ac.kr (B.-R. Koo, Kangwon Nat’l Univ.)
27 March 2026. pp. 113-118
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Abstract

Amorphous WO3･H2O films were fabricated via spin-coating of a WOCl4 solution at a low temperature of 80 °C, and the influence of gas atmosphere during film formation on electrochromic (EC) performances was systematically investigated. The films prepared under an Ar atmosphere exhibited a relatively porous morphology compared to those formed under air, which showed a more uniform and compact surface structure. These morphological differences significantly affected charge transport and electrochemical behavior. In particular, the films formed under air demonstrated enhanced electrical conductivity and faster ion transport due to the formation of a uniform surface morphology, leading to superior response speed and coloration efficiency. In contrast, films formed in the Ar atmosphere suppressed partial crystallization of WO3, thereby increasing the amorphous WO3･H2O fraction with abundant oxygen bonding sites that act as electrochemically active sites. This characteristic enabled a wider optical modulation during coloration. These results indicate that processing gas-atmosphere-controlled amorphous WO3･H2O films at low-temperature is an effective strategy for improving EC performance and expanding their applicability to flexible devices and energy-efficient smart window technologies.

Keywords
amorphous WO3･H2O
gas atmosphere
low-temperature process
electrochromic performances
spin coating
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Information
  • Publisher :Materials Research Society of Korea
  • Publisher(Ko) :한국재료학회
  • Journal Title :Korean Journal of Materials Research
  • Journal Title(Ko) :한국재료학회지
  • Volume : 36
  • No :3
  • Pages :113-118
  • Received Date : 2026-02-02
  • Revised Date : 2026-02-16
  • Accepted Date : 2026-02-19
  • DOI :https://doi.org/10.3740/MRSK.2026.36.3.113
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