of the synthetic diamond Dsyn(0.1–1 _m), Fig. 1 [54]. The surfacechemical composition of Dsynand ND is rather close and showshigh oxygen content, but ND contains a substantial amount ofnitrogen, which was, possibly, incorporated from the explosive pre-cursors during the detonation synthesis [29,31]. In comparison tosp3-hydridised diamond-base materials, sp2-hybidised graphene-based materials had a notably lower surface oxygen content likelybecause graphene sheets are prone to functionalization only at theedges and defects, while diamonds have reactive carbon bondsthroughout its surface [55]. Nitrogen-doped CNF contained signif-icant amount of nitrogen, which was likely incorporated into thestructure during the synthesis from acetonitrile