A novel porous graphitic carbon nitride (g-C7N3) substrate: prediction of metal-based π–d conjugated nanosheets toward the highly active and selective electrocatalytic nitrogen reduction reaction

The novel porous g-C 7 N 3 offers rich hollow sites for stably anchoring transition-metal atoms to promote single-atom catalysis, which is expected to overcome the great challenges of low activity and selectivity for ammonia synthesis.