Graphene Oxyhydride Catalysts in View of Spin Radical Chemistry

Abstract

The article discusses carbocatalysis provided with amorphous carbons. The discussion is conducted from the standpoint of the spin chemistry of graphene molecules, in the framework of which the amorphous carbocatalysts are a conglomerate of graphene-oxynitrothiohydride stable radicals presenting the basic structural units (BSUs) of the species. The chemical activity of the BSUs atoms is reliably determined computationally, which allows mapping the distribution of active sites in these molecular catalysts. The presented maps reliably evidence the BSUs radicalization provided with carbon atoms only, the non-terminated edge part of which presents a set of active cites. Spin mapping of carbocatalysts active cites is suggested as the first step towards the spin carbocatalysis of the species.

sp2 Carbon Stable Radicals

“…Nevertheless, in fact, by now there have not been communications joining radical terminology and the vast available data concerning sp 2 amorphous carbons. At the same time, specific peculiarities concerning metal free carbocatalysis [95][96][97][98][99][100][101][102][103][104][105][106] (see a brief review of the latter state of art [107]) and electron-spin resonance [108][109][110][111][112][113][114][115] have been really observed. However, until now, they have not been connected with specific radical properties of sp 2 carbons as well.…”

Graphene Domain Signature of Raman Spectra of sp2 Amorphous Carbons

“…Simultaneously, the presence of oxygen in the best graphites itself (the finding should be typical for all graphites [16]) evidences the limited size of BSUs as well as the unavoidable termination of the latter in the circumference. As for the weakening of the radicalization of BSU as its size grows, the issue, in particular, explains the well-known empirical fact that enforced additional fragmentation leading to nanostructuring of initial sp 2 ACs significantly enhances the yield of the reaction when these amorphics are used as carbocatalysts [46,47].…”

Amorphous state of sp2 solid carbon

“…However, as can be seen from the figure, increasing the molecule size leads to decreasing edge atoms number due to which, at a fixed atomic composition C: O: H, the number of non-terminated atoms and the degree of the associated radicalization decrease. The weakening of the radicalization of BSU as its size grows, in particular, explains the well-known empirical fact that enforced additional fragmentation leading to nanostructuring of initial synthetic sp 2 ACs significantly enhances the yield of the reaction when these amorphics are used as carbocatalysts [44,45].…”