Biosensing Frontiers: MXenes and Their Composites

Since its invention during 2011, MXenes become a popular material with diverse and tailorable properties among the material researchers. Attractive combination of properties including impressive electrical and ionic conductance, large surface to volume ratio and effective surface area for a specified application, hydrophilic character, high ionic diffusion capacity to make suitable for electrode/electrolyte interfaces preparation, biocompatibility, and easy to functionalize using various organic and inorganic moieties. MXenes are 2D layered structures of metal carbides, nitrides or a combination of both. A general formula of Mn+1Xn can be used to represent MXenes as M stands for an early transition metal and X for carbon and/or nitrogen. The unique properties and excellent compatibility with other nanomaterials and polymers make these materials suitable for high end applications including biosensing, charge storage, energy harvesting, catalysis etc. Specific composition and 2D layered structure make MXenes highly suitable for fabricating highly specific and sensitive biosensing devices. Good electrical/ionic conductance along with excellent energy transduction process opens a wide application window for MXenes in biosensor industry. Another important aspect is the multilayer structure can support effective immobilization of various biomolecules and retention of activity after multiple biosensing cycles. This book chapter describes the progress happened in this area of MXene and its composites as effective materials for the preparation of various popular biosensing devices. In particular, various morphologies of MXenes and its significance on biosensing characteristics were detailed.