Rational design of periodic porous titanium nitride MXene as a multifunctional catalytic membrane

Inspired by the experimental realization of lattice-porous graphene and mesoporous MXenes, the possibility of lattice-penetrated porous titanium nitride, Ti12N8, was proposed and verified by density functional theory calculations. Stabilities, together with mechanical and electronic characteristics, are investigated and systemically discussed: both pristine and terminated (-O, -F, -OH) Ti12N8 show great thermodynamic and kinetic stabilities; the reduced stiffness introduced by lattice pores makes Ti12N8 better candidates for functional heterojunctions with less lattice mismatch. Subnanometer-sized pores increased the number of potential catalytic adsorption sites, and terminations allowed the band gap of MXene to reach 2.25 eV. Moreover, by changing terminations and introducing lattice channels, Ti12N8 could be expected to be used for different applications: direct photocatalytic water splitting, excellent H-2/CH4 and He/CH4 selectivity and admirable HER/CO2RR overpotentials. Such excellent characteristics could provide another possible path for flexible nanodevices with tunable mechanics, electronics and optoelectronics properties.

Automated summary

Inspired by lattice-porous graphene and mesoporous MXenes, lattice-penetrated porous titanium nitride, Ti12N8, was proposed and verified using density functional theory calculations. The study investigated the stabilities, mechanical and electronic characteristics of Ti12N8 and found that it exhibited high thermal and kinetic stabilities, reduced stiffness, and increased catalytic adsorption sites. With different terminations and lattice channels, Ti12N8 showed potential for various applications such as photocatalytic water splitting and selective gas adsorption. These excellent characteristics make Ti12N8 a promising material for flexible nanodevices with tunable properties.