A Heterojunction Photodiode Operating at Inorganic Nanosheet Interfaces

摘要

A heterojunction photodiode was fabricated by forming two contact regions on a glass substrate: one side was a cast film of perovskite-type niobate [(CH_3)_3NHSr_2Nb_3O_(10)] as a n-type photosemiconductor and the other side a cast film of Zn-saponite (Na_(0.96)[Si_(7.18)Al_(0.64)]Zn_(6.20)O_(20)-(OH)_2) as a p-type semiconductor under oxygen atmosphere. Diode-type current-voltage characteristics were obtained under the illumination of light (340 nm) and oxygen atmosphere (1 atm) at 25-100 ℃. The interfacial structure was studied by means of focused ion-beam and transmission electron microscopy techniques, confirming the contact of the two different nanosheets on a nanometer scale. The results are discussed on the basis of the nanosheet band structures.