Layered double hydroxides: recent progress in electrochemical applications

Institut de Chimie de Clermont-Ferrand, Université Clermont Auvergne

Contact : sylvie.chardonuniv-grenoble-alpes.fr (Sylvie Chardon)

Layered double hydroxides (LDH) are synthetic lamellar solids with positively charged brucite-like layers of mixed metal hydroxides separated by interlayer hydrated anions, defined by the general formula [M²⁺_1-xM³⁺_x(OH)₂]^x+[(A^n-)_x/n, y H₂O] (abbreviated as M²⁺M³⁺-A, where M²⁺and M³⁺are respectively divalent and trivalent metals and A^n-is the interlayer anion compensating the positive charge of the metal hydroxide layers). These lamellar materials are often used as host matrices of organic anions, macromolecules or biomolecules. In a general point of view, the increasing interest in LDH arises from their versatile properties in terms of chemical composition of both layer and interlayer, their high and tunable layer charge density resulting in adaptable anion exchange capacity that opens a large panel of applications, i.e.  in medicine  (therapeutic vectors), in polymer nanocomposites (flame retardants, anticorrosion) or in environmental technologies [1]
Interestingly electroactive cations (Ni, Co, Fe, Mn) present in the layer structure [2] and/or intercalated redox active anions [1, 3] confer to these lamellar materials specific electrochemical properties. Consequently these LDH properties have raised the attention of the electrochemist community for the development of new applications of LDH-based modified electrodes. The relevance of LDH-based materials in electrochemical detection (chemical sensors and biosensors), energy-storage devices (supercapacitors) or electrochromism, will be presented, summarizing the most recent results of our laboratory in this topic. 

1. Taviot-Guého C. , Prévot V. , Forano C. , Renaudin G. , Mousty C., Leroux F. , Adv. Funct. Mater. 2018 28, 1703868.
2. Vialat, P.; Leroux, F.; Mousty, C.,  J. Solid State Electrochem. 2015,19, 1975-1983.
3. Mousty, C.; Prevot, V., Anal. Bioanal. Chem.2013, 405, 3513.