Water in porous carbons

We present an overview of progress in understanding the behavior of water i n porous carbons at the molecular level. We survey experimental investigati ons, semi-empirical approaches, and simulation studies. Experimental work f aces a number of challenges: the determination of the distribution of carbo n microcrystal sizes, the densities and species of surface groups, the topo logical nature of the connected pore structure, and pore size distributions . The lack of experimental characterization, together with the uncertainty in the intermolecular potentials involved, has thwarted molecular simulatio n efforts thus far. A concerted approach that links experimental and simula tion efforts appears promising in gaining a better understanding of the beh avior of water in porous carbons. Experimental results could aid in the dev elopment of realistic carbon models and improve the intermolecular potentia ls used in the simulation studies. In a complementary fashion, molecular si mulation could help improve characterization methods of both the carbon str ucture and the surface chemistry. (C) 2001 Elsevier Science B.V. All rights reserved.