Nickel Boost Helps Cobalt Phosphate Catalyst Destroy Ethanol at Lower Temperatures

A nickel-modified cobalt phosphate catalyst has shown stronger performance in the total oxidation of ethanol, a volatile organic compound whose removal matters for air quality. Researchers synthesized nickel-incorporated cobalt phosphate (Ni-CoP) catalysts using both co-precipitation and impregnation methods to explore how structural properties shape catalytic behaviour in ethanol oxidation. Their results, published in Environmental Science and Pollution Research, show that adding 10 wt% nickel allowed complete ethanol conversion at 310 °C with a CO2 selectivity of 96%, whereas undoped cobalt phosphate needed 328 °C to reach full conversion.

The team characterized the materials with an extensive suite of techniques, including XRD, BET, DRIFTS, FESEM/EDX, XPS, H2-TPR, NH3-TPD and CO2-TPD. This advanced characterization confirmed that incorporating nickel produced several measurable changes in the catalyst. The modified material had a smaller crystallite size and reduced acidity, while its basicity increased. Nickel incorporation also facilitated redox activity through the formation of a NiCoP4O12 mixed phase, a structural change the authors link directly to the improved catalytic behaviour.

According to the study, these physicochemical changes are what enabled the lower-temperature performance. The researchers emphasize the critical role of acid-base surface modification and synergistic metal-phosphate interactions in designing catalysts for VOC abatement.

Stability was another focus of the investigation. In repeated reaction cycles, the Ni-CoP catalyst maintained high activity and selectivity, exhibiting only a modest shift in its light-off temperature. The authors present this cycling behaviour as evidence that the nickel-modified material is a stable candidate for sustained use in ethanol oxidation, rather than a catalyst whose performance degrades quickly under reaction conditions.

The study was carried out by Souad Mokhliss, Tiina Laitinen, Noura Majoudi, Satu Ojala, Rachid Brahmi and Mahfoud Agunaou, and published in 2026. Its central contribution is the demonstrated correlation between structural modification and catalytic performance: by tuning the acid-base properties and creating a mixed nickel-cobalt phosphate phase, the catalyst converts ethanol completely to carbon dioxide at a temperature 18 °C lower than the undoped material. The findings underscore how targeted surface chemistry can improve both the efficiency and the durability of catalysts intended for volatile organic compound abatement.

Subject of Research: Nickel-modified cobalt phosphate catalysts for the total oxidation of ethanol

Article Title: Nickel-modified cobalt phosphate: physicochemical properties and catalytic performance in the total oxidation of ethanol

Article References: Mokhliss, S., Laitinen, T., Majoudi, N., Ojala, S., Brahmi, R., & Agunaou, M. (2026). Nickel-modified cobalt phosphate: physicochemical properties and catalytic performance in the total oxidation of ethanol. Environmental Science and Pollution Research. https://doi.org/10.1007/s11356-026-38336-0

Image Credits: AI Generated

DOI: 10.1007/s11356-026-38336-0

Keywords: cobalt phosphate, nickel catalyst, ethanol oxidation, VOC abatement, heterogeneous catalysis, CO2 selectivity, catalyst stability, redox activity, acid-base properties, co-precipitation, Nickel-modified, cobalt