Irradiation of detonation nanodiamonds with γ-rays does not produce long living spin radicals

Detonation nanodiamonds of 5nm size with the surface terminated by carboxyl and/or hydroxyl groups, which act as radical scavengers, represent promising nanofillers for polymer composites. Irradiation of the nanodiamonds with ¹³⁷Cs γ-rays does not produce long living paramagnetic species both inside the crystalline core and in the outer molecular shell. The reason is rapid interaction of the radiation-induced surface radicals with physisorbed water, molecular oxygen and oxidizing products of their radiolysis.