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bstract

The burgeoning urbanization, population explosion, and climate change have triggered the development of sustainable energy technologies for a greener future. Hydrogen energy is considered to be the best solution for the ever-increasing energy demand. The development of electrocatalysts for the hydrogen production plays a pivotal role. Sustainable and low-cost materials with excellent electrocatalytic performance is highly preferred for photocatalytic and electrocatalytic hydrogen production. Graphitic carbon nitride (g-C 3N 4) is a versatile layered two-dimensional material for the hydrogen evolution reaction (HER). A comprehensive review that investigates the effect of doping on the photocatalytic and electrocatalytic HER is lacking in the literature. This motivates us to write a detailed review on g-C 3N 4-based catalysts for sustainable hydrogen production via both photocatalysis and electrocatalysis. This review encompasses the salient features of g-C 3N 4-based electrocatalysts, doping in g-C 3N 4, their photocatalytic and electrocatalytic HER activities, and their performance evaluation. This review proclaims that doping is an effective strategy to enhance the catalytic performance of g-C 3N 4-based catalysts for sustainable hydrogen production.