Photoconductivity in sprayed β-In2S3 thin films under sub-band-gap excitation of 1.96 eV

Abstract

β -In 2 S 3 thin films with a band gap of ∼2.67eV exhibited persistent photoconductivity when excited using photons with energy of 1.96 eV. The photoconductive response to extrinsic photoexcitation could be removed when the film stoichiometry was changed. Photoluminescence studies in the films revealed an emission of 1.826 eV, due to donor–acceptor pair (DAP) recombination, which was absent in the film not responding to extrinsic excitation. Hence, it was concluded that presence of the DAP was responsible for the extrinsic photoconductivity under the 1.96 eV excitation. This study can initiate further a methodology for tailoring the photoresponse of this semiconducting thin film by spatially controlling the film stoichiometry.

In2S3 nanomaterial as a broadband spectrum photocatalyst to display significant activity

“…In the NIR light region, the In 2 S 3 nanoparticles show absorption and display two obvious broad absorption peaks at 1440 nm and 1940 nm (Fig. 5b), which can be ascribed to the presence of a defect band located above the valence band of ␤-In 2 S 3 as reported by Jayakrishnan et al [40]. The good NIR photocatalytic performance of the In 2 S 3 nanoparticles can be attributed to the absorption of NIR light.…”

“…Meanwhile, sulfur vacancies and oxygen in the assynthesized In 2 S 3 nanoparticle surfaces may help to form a defect band above the valence band of In 2 S 3 nanoparticles [28]. The defect band not only produces the absorption of NIR light, but also favors the separation of carriers by first trapping the electrons and then slowly releases these electrons into the conductive band [40]. However, to give a more detailed explanation for the NIR photocatalytic activity of the as-prepared In 2 S 3 nanoparticles, their electronic band structure should be explored in the future research.…”

Thermally-assisted photodegradation of lignin by TiO2/H2O2 under visible/near-infrared light irradiation

“…This temperature-induced variation of photocurrent is coincident with the variation of thermally-assisted photodegradation performance of the TiO 2 /H 2 O 2 thermally-assisted photocatalytic system, further corroborating the importance of the transfer and separation of charge carriers in the thermally-assisted photocatalytic process. Meanwhile, dark current is detected at elevated temperatures, which may be ascribed to thermally-assisted induced carrier generation [21] and H 2 O 2 -promoted separation of charge carriers [9].…”

Aluminum Doped ZnO Thin Films Using Chemical Spray Pyrolysis

“…Photoluminescence studies were performed in an in-house assembled PL scanning system, by exciting the samples with 325 nm line of a He-Cd laser (Kimmon) and the emission spectrum was recorded using a USB2000 spectrophotometer. Details of the PL system were reported by us [26]- [28]. Electrical measurements were carried out using silver contacts separated by a distance of 1 cm.…”