Transition metal nitrides are well-known 3D superconductor materials. However, there is a lack of knowledge related to their two-dimensional (2D) counterparts, which have several potential technological applications. 
In this work, we predict, using an evolutionary algorithm coupled with a first-principles approach, a set of novel 2D superconductive structures based on tungsten nitride. 
Through a systematic process including energetic and dynamical analysis, three thermodynamically stable compositions along with metastable compounds were studied in the following stoichiometries: W$_4$N$_2$, W$_2$N$_2$, and W$_2$N$_3$. Their superconductive temperature ($T_c$) values, estimated by means of the Eliashberg superconductive theory and the McMillan equation, range from 2.3 to 21.6 K, where the highest $T_c$ value corresponds to a W$_2$N$_3$ metastable hexagonal system. A systematic analysis of the structural, electronic, vibrational and electron-phonon properties, allowed us to recognize the variables that modulate the $T_c$ in theses systems. The superconductive behavior is strongly affected by changes in the nitrogen density of states at Fermi level, the electron-phonon coupling constant and the lattice symmetry. The present results aim to encourage further theoretical and experimental efforts over non fully explored superconductors in two dimensions.
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