Transition Metals Embedded Two-Dimensional Square Tetrafluorotetracyanoquinodimethane Monolayers as a Class of Novel Electrocatalysts for Nitrogen Reduction Reaction

The combination of transition metal (TM) atoms and high electron affinity organic framework tetrafluorotetracyanoquinodimethanes (F(4)TCNQs) makes the TM-embedded two-dimensional (2D) square F(4)TCNQ monolayers (TM-sF(4)TCNQ) possible to have excellent characteristics of single-atom catalysts and 2D materials. For the first time, the TM-sF(4)TCNQ monolayers have been considered for application in the electrocatalytic nitrogen reduction reaction (eNRR) field. Through high-through put screening, the catalytic performance of 30 TM-sF(4)TCNQ (TM = 3d similar to 5d TMs) monolayers for eNRR was comprehensively evaluated. The Mo-, Nb-, and Tc-sF(4)TCNQ catalysts stand out with the onset potentials of -0.18, -0.44, and -0.54 V, respectively, through the optimal reaction paths. Our work will provide guidance for the green and sustainable development of electrocatalytic nitrogen fixation.

Automated summary

The combination of transition metal atoms and high electron affinity organic framework tetrafluorotetracyanoquinodimethanes (F(4)TCNQs) enables the TM-embedded two-dimensional square F(4)TCNQ monolayers (TM-sF(4)TCNQ) to possess characteristics of both single-atom catalysts and 2D materials. By conducting high-throughput screening, the catalytic performance of 30 TM-sF(4)TCNQ monolayers (TM = 3d to 5d TMs) for electrocatalytic nitrogen reduction reaction (eNRR) was comprehensively evaluated. Among them, Mo-, Nb-, and Tc-sF(4)TCNQ catalysts showed outstanding onset potentials of -0.18, -0.44, and -0.54 V, respectively, through the optimal reaction paths. This study provides guidance for the green and sustainable development of electrocatalytic nitrogen fixation.