▎ 摘　　要

NOVELTY - Producing aerogel or xerogel comprising graphene, graphene oxide or its mixture involves: (a) dispersing graphene, graphene oxide or its mixture in solvent compatible to it; (b) cross-linking the graphene, graphene oxide or its mixture via functional groups present on graphene and/or the graphene oxide, or with a linking molecule comprising at least two functional sites capable of reacting with the surface of graphene and/or graphene oxide, to form covalently cross-linked gel network; and (c) removing solvent to produce cross-linked aerogel or xerogel with solvent content of less than 10%. USE - The methods are useful for producing aerogel or xerogel comprising graphene, graphene oxide or its mixture; and for heating graphene or graphene oxide aerogel or xerogel (all claimed). ADVANTAGE - Electrically heatable graphene and graphene oxide aerogels/xerogels are provided which have high surface area, and which are highly interconnected to provide robust networks that are attractive for applications such as filtration, sorption, gas storage and catalyst support. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for: (1) an aerogel obtainable by the method; or an aerogel having a density of from 1 to 3000 mg/cm3, comprising a network of graphenes, and optionally further comprising any of the features above; (2) a xerogel obtainable by the method; (3) a catalyst or catalyst support comprising the aerogel or xerogel; (4) non-reflective panels comprising the aerogel or xerogel; (5) electrochemical device electrodes comprising the aerogel or xerogel; (6) an absorbent material for solvent, oil, petrol and liquid absorption, comprising the aerogel or xerogel; (7) a filter comprising the aerogel or xerogel; (8) a gas adsoption medium comprising the aerogel or xerogel; (9) a water purification medium comprising the aerogel or xerogel; (10) a method of heating a graphene or graphene oxide aerogel or xerogel involving: (a) providing a graphene aerogel or xerogel, or a graphene oxide aerogel, xerogel or gel; and (b) applying an electrical current to it; (11) a gas or liquid heating device comprising an aerogel, xerogel obtainable by the method; (12) an electrically-regenerable filter or sorbent comprising the aerogel or xerogel obtainable by the method; and (13) a fluid heater comprising the aerogel or xerogel obtainable by the method.