Researchers have developed a continuous flash Joule heating method to produce scalable and general fusion ternary metal oxides with triple-active Fenton-like activity, as reported in a recent study published in Engineering. This innovative approach, utilizing a programmable logic controller (PLC) with robotic arms, has successfully demonstrated the proof-of-concept for large-scale production of these advanced materials.

The study, led by Xiangdong Zhu, Fengbo Yu and Yujun Wang, addresses the challenge of synthesizing multimetal oxides with asymmetric atomic sites for enhanced Fenton-like reactions. Traditional methods often suffer from long-duration processes and inferior material characteristics due to phase separation and aggregation. However, the continuous flash Joule heating technique overcomes these limitations by rapidly heating and cooling the materials, promoting the fusion of different metals and enhancing their synergistic catalytic reactions.

The continuous production system achieved a pilot-scale product output of 178.3 kg·h⁻¹·m⁻² electrode for flow-through water treatment. The integration of multiple reaction electrodes with independent power supplies further outlines a path for increased production. “Experiments and density functional theory calculations proved that the fusion CuVFeO structure achieved dual functionality of organics adsorption on Cu sites and peroxydisulfate activation on Fe sites,” the researchers noted. The synergistic reaction is strengthened by V doping, which endows the structure with a d band center, leading to an increased Fe Bader charge.

The study also highlights the practical applicability of the method through continuous water treatment applications. The CuVFe material demonstrated superior performance during long-term operations, maintaining high efficiency for over 1455 min in a continuous flow-through device. The continuous flash Joule heating characterization determined that multiple transition metals (CuVFe, CoVFe, MgVFe) can be generally synthesized with superior catalytic performance.

The researchers emphasized the importance of the fusion structure in enhancing the utilization and production efficiency of free radicals. “Triple site effects shorten the reaction distance between free radicals (SO₄^•− and •OH) and organics, enhancing free radicals’ utilization and production efficiency,” they explained. The study also revealed that the Cu component facilitates the adsorption of organic pollutants, while the Fe site provides electrons for peroxydisulfate activation.

The continuous flash Joule heating method offers significant advantages for the scalable production of advanced oxidation materials. The ultra-high temperature and rapid cooling rate promote the formation of multimetal oxides, overcoming compatibility issues among multiple metal components. The study concludes that this method holds great potential for practical applications in wastewater treatment, offering high purification efficiency and stability.

This research not only provides a scalable solution for the production of advanced oxidation materials but also offers valuable insights into the synthesis-structure-properties relationships and synergistic mechanisms of multimetal oxides. The continuous flash Joule heating technique is expected to play a crucial role in the development of next-generation materials for environmental applications.

The paper “Continuous Joule Heating for Scalable and General Fusion Ternary Metal Oxides with Triple-Active Fenton-Like Activity,” is authored by Xiangdong Zhu, Beibei Xiao, Fengbo Yu, Chao Jia, Liming Sun, Shicheng Zhang, Lianli Wang, Peixin Cui, Liang Wang, Xiaoguang Duan, Shaobin Wang, Yujun Wang. Full text of the open access paper: https://doi.org/10.1016/j.eng.2025.06.004. For more information about Engineering, visit the website at https://www.sciencedirect.com/journal/engineering.