Carrier cooling dynamics

Photo-induced electron transfer reactions from quantum well electrodes into a redox system in solution represent an intriguing research area of photoelectrochemistry. Several aspects of quantized semiconductor electrodes are of interest, including the question of hot carrier transfer from quantum well electrodes into solution. The most interesting question here is whether an electron transfer from higher quantized levels to the oxidized species of the redox system can occur, as illustrated in Fig. 9.31. In order to accomplish such a hot electron transfer, the rate of electron transfer must be competitive with the rate of electron relaxation. It has been shown that quantization can slow down the carrier cooling dynamics and make hot carrier transfer competitive with carrier cooling. 

The device thus makes it possible to maintain a water partial pressure ranging between 3.3 x lO " and 0.08 atm. It can be seen that the higher value is relatively low, so we could increase it by raising the temperature of the devices intended to heat the whole of the conduits but we are generally limited by the cooling water of the external walls of the furnaces, which, to play its part of cooling, must be at a low temperature and which, often, is the cause of condensation in the neighborhood of the upper part of the furnace, ft is obvious that the method is appropriate to create static atmospheres. To create dynamic atmospheres, we can get across the water container by inert carrier gas with sufficiently low flows to allow liquid water equilibrium to be established. 

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