Abstract: A novel non-woven fiber web comprising a plurality of first fibers orientated in the x-, y-, and optionally z-directions, said first fibers being bonded with a polymeric substance, characterised in that one or more continuous strands are embedded within the sub-surface layer of the non-woven fiber web, each continuous strand comprising a plurality of second carbon fibers, is disclosed. A gas diffusion substrate, electrode and membrane electrode assembly comprising said web is also disclosed, all of which may have application in electrochemical devices, for example in a fuel cell.

Abstract: A novel gas diffusion substrate comprising a porous structure and a filler material, characterised in that the filler material comprises a base filler material which is electrically conducting and carbonaceous and one or more modifier materials which ate hydrophilic in nature relative to the base filler material; a porous gas diffusion electrode comprising said substrate and the use of said substrate or electrode in a fuel cell is disclosed.

Abstract: A non-woven fibre web comprising a plurality of first fibres of amorphous silica, said first fibres being orientated in the x-, y- and optionally z-direction, and optionally being bonded with one or more binder substances, characterised in that one or more continuous strands are embedded within the non-woven fibre web, each continuous strand comprising one or more second fibres of amorphous silica, and a method for the manufacture thereof is disclosed. Also disclosed is an ion-conducting membrane comprising said non-woven web and the use thereof, in particular, in a fuel cell.