Abstract: The present invention provides use of a porous carbon material in a metal air battery, wherein the porous carbon material (a) has a specific surface area (BET) of 100-600 m2/g, and (b) has a micropore area of 10-90 m2/g. The present inventors have found that this porous carbon material exhibits advantageous properties such as corrosion resistance.

Abstract: An air-breathing cathode includes (i) a conductive current collector; (ii) a metal-ion conducting medium; and a metal oxide of formula (AA?)a(BB?)bOc. wherein: A and A? are the same or different and selected from RE (which is yttrium, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium), magnesium, calcium, strontium, barium, lithium, sodium, potassium, indium, thallium, tin, lead, antimony or bismuth; B is Ru, Ir, Os, Rh, Ti, Sn, Ge, Mn, Ta, Nb, Mo, W, Zr or Pb; B? is absent or selected from Ru, Ir, Os, Rh, Ca, Mg, In, Tl, Sn, Pb, Sb, Bi, Ge, Ta, Nb, Mo, W, Zr or RE; c is from 3-11; the atomic ratio of (a+b):c is from 1:1 to 1:2; the atomic ratio of a:b is from 1: 1.5 to 1.5:1 and at least one A and/or A? is an alkali metal, alkaline earth metal or RE.

Abstract: A novel catalyst comprising a Pt--M alloy wherein M is one or more metals selected from the transition metal elements or from Groups IIIA or IVA of the Periodic Table in "Handbook of Chemistry and Physics" 64th Edition, CRC Press, and Y wherein Y is a bronze forming element or an oxide thereof, characterised in that the Pt--M alloy is in intimate contact with Y, and provided that M is not Ru if Y is WO.sub.3 is disclosed and which may be used as a poison tolerant catalyst for use in fuel cells, specifically as the anode of a PEM fuel cell.