For sustainable energy technologies, MXenes offer unique properties such as high electrical conductivity, hydrophilicity, excellent thermal stability, large interlayer spacing, easily tunable structure, high surface area, and microporous structure that facilitate faster ion transfer. To address limitations of aqueous MXene suspension, Ti3C2-type MXene thin films are prepared from non-aqueous suspensions in N,N-dimethyl formamide (DMF) and N-methyl-2-pyrrolidone (NMP) using solvent exchange method followed by spin coating or drop casting on gold interdigitated electrodes (IDE) and ceramic substrates and their electrical properties are compared. Electrical properties investigated by impedance spectroscopy (4 Hz to 8 MHz) and four-point probe (FPP) measurements show that DMF-MXene layers exhibit higher electrical conductivity than MXene deposited from NMP. The material technology and electrical properties of MXene thin films prepared from non-aqueous solvents may thus be promising for possible use of MXenes in hybrid photovoltaic devices as charge-transporting layers.

Electrical properties of MXene thin films prepared from non-aqueous polar aprotic solvents

Soft bioelectronic interfaces for mapping and modulating excitable networks at high resolution and at large scale can enable paradigm-shifting diagnostics, monitoring, and treatment strategies. Yet, current technologies largely rely on materials and fabrication schemes that are expensive, do not scale, and critically limit the maximum attainable resolution and coverage. Solution processing is a cost-effective manufacturing alternative, but biocompatible conductive inks matching the performance of conventional metals are lacking. Here, we introduce MXtrodes, a novel class of soft, high-resolution, large-scale bioelectronic interfaces enabled by Ti3C2 MXene and scalable solution processing. We show that the electrochemical properties of MXtrodes exceed those of conventional materials, and do not require conductive gels when used in epidermal electronics. Furthermore, we validate MXtrodes in a number of applications ranging from mapping large scale neuromuscular networks in humans to delivering cortical microstimulation in small animal models. Finally, we demonstrate that MXtrodes are compatible with standard clinical neuroimaging modalities.

/pdf/mxtrodes-mxene-infused-bioelectronic-interfaces-for-11pktxls7s.pdf

M. Sergison

Papers

MXtrodes: MXene-infused bioelectronic interfaces for multiscale electrophysiology and stimulation