Charge-trapping capability and AC conductivity at different humidities of poly(ethyleneimine)–TiO2–anthocyanin-modified cellulose fibres

Modified cellulose materials are finding increasing application in electronics, because of the need for more environmental-friendly electronic circuits. The papers prepared from poly(ethyleneimine)–TiO₂–anthocyanin-modified cellulose fibres are completely environmentally friendly and can be applied to the construction of photocells or photo-/humidity sensors. To better understand the mechanisms of electrical conductivity of the said cellulose composites, the effect of humidity (RH = 9% → 100%) on its dielectric properties is presented in this article. The possibility of trapping the negative and positive charges in the composite under different humidity conditions is also examined. A large number of studies suggest that proton conductivity, stimulated by humidity, is the dominant mechanism of electrical conductivity in cellulose-based materials. The results presented in this paper indicate that the electronic conductivity mechanisms also play a significant role in papers prepared from poly(ethyleneimine)–TiO₂–anthocyanin-modified cellulose fibres.