Stable and fast oil recovery by environmentally friendly and easy to synthesize pristine graphitic carbon nitride

Fast oil recovery from the ocean after an oil spill is crucial before permanent damage happens to the ecological balance and marine life. Sorbents that are usually used to recover oil from water are not environmentally friendly and involve complicated synthesis routes. Against this backdrop, we have discovered that pristine porous graphitic carbon nitride (GCN), as developed here via a one-step one precursor (i.e., melamine) facile synthesis route, is a high-capacity and stable oil sorbent. The GCN, sans any additive/support, has exhibited > 100% oil adsorption, at a rapid rate, for different types of oils from the surface of as-prepared artificial sea water; with the capability of it being reused multiple times, without any detectable change in the structure or drop in adsorption %, after simply burning off the adsorbed oil in air. As established here, the ‘oil take-up’ happens via physisorption, sans any chemical reaction/change of GCN structure/bonds post-adsorption, which renders the sorbent material highly stable. Hence, this work demonstrates the superior oil adsorption capabilities of easy-to-synthesize, scalable, and environmentally friendly GCN, toward a straightforward, eco-friendly, and widespread oil recovery solution. Graphical abstract