Computational Design of Gas Sensors Based on V 3 S 4 Monolayer.

Novel magnetic gas sensors are characterized by extremely high efficiency and low energy consumption, therefore, a search for a two-dimensional material suitable for room temperature magnetic gas sensors is a critical task for modern materials scientists. Here, we computationally discovered a novel ultrathin two-dimensional antiferromagnet V 3 S 4 , which, in addition to stability and remarkable electronic properties, demonstrates a great potential to be applied in magnetic gas sensing devices. Quantum-mechanical calculations within the DFT + U approach show the antiferromagnetic ground state of V 3 S 4 , which exhibits semiconducting electronic properties with a band gap of 0.36 eV. A study of electronic and magnetic response to the adsorption of various gas agents showed pronounced changes in properties with respect to the adsorption of NH 3 , NO 2 , O 2 , and NO molecules on the surface. The calculated energies of adsorption of these molecules were -1.25, -0.91, -0.59, and -0.93 eV, respectively. Obtained results showed the prospective for V 3 S 4 to be used as effective sensing materials to detect NO 2 and NO, for their capture, and for catalytic applications in which it is required to lower the dissociation energy of O 2 , for example, in oxygen reduction reactions. The sensing and reducing of NO 2 and NO have great importance for improving environmental protection and sustainable development.