Production of hydrogen from water via visible light driven photocatalytic water splitting is a future technology that may offer important routes to clean fuels. Graphitic carbon nitride (g C3N4) has been proven to be a suitable catalyst for this process. Its structure has been investigated for many years and is known to consist of graphitic type sheets; however, it is not fully crystalline expecially in 3 dimensions, its stoiciometry varies fron the ideal C3:N4 ratio and there is some evidence of residual H-atoms in the structure . Recent work shows that photocatalytic activity of g C3N4 for hydrogen production depends upon synthesis conditions, especially final temperature. This is thought to be linked to structure, including dimensionality, and the associated C:N:H stoichiometry, thus we propose to investigate structure and its evolution on NIMROD. linking to photoactalytic studies.