Atomic hydrogen treatment of nanodiamond powder studied with photoemission spectroscopy

The effect of atomic hydrogen treatment upon the surface of partially graphitized nanodiamonds has been studied by photoemission spectroscopy. The C1s core level peak and valence band spectra of a partially graphitized nanodiamond sample were compared with those following hydrogen treatment and following subsequent annealing. We have observed a difference in the binding energy of the sp(3) component of the C1s peak and in the valence band which we believe can be assigned to either upward or downward band bending due to surface graphitization and hydrogenation of nanodiamonds, respectively. The data confirms that the graphitic layers which initially cover the nanodiamond particles can be removed through exposure to atomic hydrogen. This method could enable the preparation of hydrogen terminated and separate nanodiamond particles.