Electrocatalytic and Optoelectronic Characteristics of the Two-Dimensional Titanium Nitride Ti4N3Tx MXene

• DOI: 10.1021/acsami.9b01150
• Publication Date: 2019-03-04T18:01:26Z
• Authors: Abdoulaye Djire; Hanyu Zhang; Jun Liu; Elisa M. Miller; Nathan R. Neale
• Keywords: MXenes; Overpotential; Surface States; Titanium carbide

A relatively new class of two-dimensional (2D) materials called MXenes have garnered tremendous interest in the field energy storage and conversion. Thus far nearly all reported experimentally been described as metals, with a lone report mixed-metal carbide phase exhibiting semiconducting character. Here, we optical, electrocatalytic, electrical properties 2D Ti4N3Tx MXene (Tx = basal plane surface terminating groups) show that this material exhbits both metallic behaviors. We provide complete structural characterization exfoliated assign Tx O and/or OH find is susceptible to oxidation. Optical experiments indicate forms hybrid thin oxide layer resulting visible light absorbtion at energies greater than ∼2.0 eV an excitation wavelength-dependent defect-state emission over broad range centered ∼2.9 eV. As electrocatalyst for hydrogen evolution reaction, shows overpotential ∼300 mV -10 mA cm-2 Tafel slope ∼190 dec-1. Finally, observe behavior temperatures below ∼90 K from temperature-dependent transport measurements under 5 T magnetic likely layer. These results unveil intriguing expands potential these into electrocatalysis (opto)electronic applications.