Capturing ion trapping and detrapping dynamics in electrochromic thin films

Zhang，Renfu1; Zhou，Qinqi1; Huang，Siyuan1; Zhang，Yiwen1; Wen，Rui Tao1,2

2024-12-01

10.1038/s41467-024-46500-8

Nature Communications   影响因子和分区

2041-1723

Ion trapping has been found to be responsible for the performance degradation in electrochromic oxide thin films, and a detrapping procedure was proved to be effective to rejuvenate the degraded films. Despite of the studies on ion trapping and detrapping, its dynamics remain largely unknown. Moreover, coloration mechanisms of electrochromic oxides are also far from clear, limiting the development of superior devices. Here, we visualize ion trapping and detrapping dynamics in a model electrochromic material, amorphous WO. Specifically, formation of orthorhombic LiWO during long-term cycling accounts for the origin of shallow traps. Deep traps are multiple-step-determined, composed of mixed W-LiWO, amorphous LiWO and W-LiO. The non-decomposable W-LiWO couple is the origin of the irreversible traps. Furthermore, we demonstrate that, besides the typical small polaron hopping between W ↔ W sites, bipolaron hopping between W ↔ W sites gives rise to optical absorption in the short-wavelength region. Overall, we provide a general picture of electrochromism based on polaron hopping. Ion trapping and detrapping were demonstrated to also prevail in other cathodic electrochromic oxides. This work not only provides the ion trapping and detrapping dynamics of WO, but also open avenues to study other cathodic electrochromic oxides and develop superior electrochromic devices with great durability.

SCI

英语

第一

2-s2.0-85187750489

Scopus

1.Department of Materials Science and Engineering,Southern University of Science and Technology,Shenzhen,518055,China
2.Guangdong Provincial Key Laboratory of Functional Oxide Materials and Devices,Southern University of Science and Technology,Shenzhen,518055,China

Zhang，Renfu,Zhou，Qinqi,Huang，Siyuan,et al. Capturing ion trapping and detrapping dynamics in electrochromic thin films[J]. Nature Communications,2024,15(1).

Zhang，Renfu,Zhou，Qinqi,Huang，Siyuan,Zhang，Yiwen,&Wen，Rui Tao.(2024).Capturing ion trapping and detrapping dynamics in electrochromic thin films.Nature Communications,15(1).

Zhang，Renfu,et al."Capturing ion trapping and detrapping dynamics in electrochromic thin films".Nature Communications 15.1(2024).