Nanosecond Pulse Radiolysis of Nanoconfined Water

The radiation chemistry of water in 1 and 57 nm pore diameter controlled pore glass is studied using nanosecond pulse radiolysis and compared to that of the bulk. The absorption spectrum of the solvated electron shows little dependence on the pore size suggesting that they solvate within the pore. It is shown that the reaction rate of the solvated electron increases dramatically with decreasing pore size, going from 6.8 × 106 s–1 in the bulk to 34.7 × 106 s–1 in a 1 nm pore. The initial yield (at 20 ns) shows an increase of 2.03 ± 0.01 in a 1 nm pore relative to the bulk. Formation of the solvated electron most likely occurs by an energy transfer process that occurs at the interface followed by diffusion into the pore.