Feasible strategies to promote the sensing performances of spinel MCo2O4 (M = Ni, Fe, Mn, Cu and Zn) based electrochemical sensors: a review

Abstract

Spinel MCo₂O₄ (M = Ni, Fe, Mn, Cu and Zn) demonstrates excellent physicochemical properties due to the combined effects of M²⁺ and Co³⁺ cations. Their inimitable optical, electronic, and mechanical properties open up windows for a broad range of promising applications. The development of novel spinels has opened virtually infinite possibilities for the development of different sensors. The association of nanomaterials with conventional electrodes or other substrates can produce completely novel and high performance sensors. The knowledge about the nanomaterials allows us to tailor sensors for desired applications. In this regard, the spinel MCo₂O₄ based materials and their composites offer great promise for the design and development of high-performance electrochemical sensors to detect target species in solution or in gas phase. Aiming to shed light on these important materials, this review presents the role of such cobaltites and their composites towards the development of electrochemical sensors with improved analytical properties for sensing in solution as well as gas phase. A critical comparison of the proposed sensors using these MCo₂O₄-based materials with other chemically-modified sensors considered the best choices in the literature for some target molecules is presented in order to demonstrate the benefits of such materials. Further, future perspectives and opportunities in these exciting research fields are also commented based on their current progress.