Space Charge Layer and Band Banding

Charge Separation and Carrier Trapping in Ti02 Nanoparticles 

Below we review the last two decades of the study of charge separation and stabilization processes in nanoparticles of Ti02 under light excitation revealed by the EPR technique. 

The fate of the trapped electron with an increase in temperature was followed in work [46] for cysteine-modified Ti02 aqueous colloid with lead ion added into solutions. It was shown that in this case lead is chelated with the carboxyl and mercapto groups of cysteine, and 

At 120 K, however, the relative intensity of the signal for lattice type Ti3+ trapped electrons decreased, and surface trapped Ti electrons with g = 1.958 (associated with Structure III) and g = 1.934 (associated with Structure II) increased (Fig. 1.5)  

When the temperature was raised to 200 K the signal for the surface trapped electrons at the sites chelated with two cysteine molecules (Fig. 1.4) disappeared, while the signal for surface trapped electrons at the sites chelated with one cysteine molecule increased four times relative to the trapped hole signal  

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