Development of molybdenum doped cerium oxide passive counter electrodes by surfactant-assisted ultrasonic spray pyrolysis

Gillissen, Florian; Colson, Pierre; Spronck, Gilles; Maho, Anthony; Cloots, Rudi; Dewalque, Jennifer

doi:10.1016/j.solmat.2025.114060

Article (Scientific journals)

Development of molybdenum doped cerium oxide passive counter electrodes by surfactant-assisted ultrasonic spray pyrolysis

Gillissen, Florian; Colson, Pierre; Spronck, Gilles et al.

2026 • In Solar Energy Materials and Solar Cells, 296, p. 114060

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https://hdl.handle.net/2268/338415

DOI
10.1016/j.solmat.2025.114060

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Keywords :

Cerium oxide; Transparent counter electrode materials; Ultrasonic spray pyrolysis; Molybdenum/heteroelement doping; Ion storage capacity

Abstract :

[en] Numerous optoelectronic systems, such as electrochromic smart windows, require efficient counter electrodes for their functional operation. Herein, cerium oxide (CeO2) based layers are considered as optically-neutral compounds of high electrochemical activity. Their deposition as thin films onto conducting glass substrates is carried out via surfactant-assisted ultrasonic spray pyrolysis, while further considering heteroelement doping with molybdenum (0–10 %at.). Highly transparent and homogeneous films are accordingly produced, demonstrating important ion storage abilities, especially in the optimal case (6 %at. Mo), bearing a 28 mC cm􀀀 2 charging capacity, together with 90+% transmittance over a large optical range. Morpho-structural characterizations additionally highlight a high homogeneity in the deposited layers, owing to the presence of the surfactant species, and enhancing the transmittance of the films. Moreover, the substitution of Ce4+ ions by Mo6+ in the crystal lattice is shown to create additional oxygen vacancies in the layers, contributing to the observed increase in charging capacity. Altogether, excellent optical and electrochemical performances are obtained from such Modoped CeO2 formulations, surpassing most of the current related literature. Finally, proof-of-concept electrochromic devices, combining Mo-doped CeO2 optically-neutral electrodes with WO3 films and involving either liquid- or solid, gel-based electrolytes, display great performances of large optical contrasts, fast kinetics, and good coloration efficiencies.

Disciplines :

Chemistry

Author, co-author :

Gillissen, Florian ; Université de Liège - ULiège > Département de chimie (sciences) > GREEnMat

Colson, Pierre ; Université de Liège - ULiège > Département de chimie (sciences) > GREEnMat

Spronck, Gilles ; Université de Liège - ULiège > Département de chimie (sciences) > GREEnMat

Maho, Anthony ; Université de Liège - ULiège > Département de chimie (sciences) > GREEnMat

Cloots, Rudi ; Université de Liège - ULiège > Département de chimie (sciences) > GREEnMat

Dewalque, Jennifer ; Université de Liège - ULiège > Département de chimie (sciences) > GREEnMat

Language :

English

Title :

Development of molybdenum doped cerium oxide passive counter electrodes by surfactant-assisted ultrasonic spray pyrolysis

Publication date :

March 2026

Journal title :

Solar Energy Materials and Solar Cells

ISSN :

0927-0248

Publisher :

Elsevier

Volume :

296

Pages :

114060

Peer reviewed :

Peer Reviewed verified by ORBi

Additional URL :

https://api.elsevier.com/content/article/PII:S0927024825006610?httpAccept=text/xml

Funders :

F.R.S.-FNRS - Fund for Scientific Research
ANR - French National Research Agency

Funding text :

F.R.S.-FNRS Conventions PDR T.0125.20 "PLASMON_EC" and M-ERA.NET R8002.23 "PECLABEL"). A. Maho’s “Chaire de Professeur Junior” supported by the French National Research Agency (ANR) and by the French Ministry for Higher Education and Research.

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