Surface induced charge transfer in Cu_xIn_2-xS₃ nanostructures and their enhanced photoelectronic and photocatalytic performance

다국어 초록 (Multilingual Abstract)

<P><B>Abstract</B></P> <P>Multi-functional semiconducting nanostructures are gaining popularity for application in photoelectronics, energy storage devices and also in industrial and environmental remediation functions. In this regard, Cu<SUB>x</SUB>In<SUB>2-x</SUB>S<SUB>3</SUB> nanostructures were investigated in detail for their photoelectrical and photocatalytic performance. Their physico-chemical characteristics were at first studied using X-ray diffraction, Raman, UV–vis absorbance, X-ray photoelectron spectroscopy and high resolution electron microscopic tools. Cu<SUB>x</SUB>In<SUB>2-x</SUB>S<SUB>3</SUB> based flip chip Schottky diodes were demonstrated to attest their improved conductivity and enhanced photoelectrical performance. The photo switching capabilities of a type II <I>p-n</I> CdTe/Cu<SUB>x</SUB>In<SUB>2-x</SUB>S<SUB>3</SUB> heterojunction was also investigated. In both the device configurations, the current-voltage (I-V) characteristics revealed the forward current and rectification ratio to improve under lower threshold voltages. The time-dependent photoresponse characteristics affirmed the stability of diodes, augmenting the improved/effective separation of photo generated electron hole pairs under illumination. Additionally, the photocatalytic performances of Cu<SUB>x</SUB>In<SUB>2-x</SUB>S<SUB>3</SUB> nanostructures were inferred under visible light conditions through effective remediation of methylene blue (MB) dye molecules. The obtained results infer the Cu interaction in tetragonal lattice of Cu<SUB>x</SUB>In<SUB>2-x</SUB>S<SUB>3</SUB> to promote the surface induced charge transfer mechanism in respective nanostructures, thereby enhancing their photoelectronic and photocatalytic functionalities.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Cu<SUB>x</SUB>In<SUB>2-x</SUB>S<SUB>3</SUB> multi-functional nanostructures were fabricated by hydrothermal route. </LI> <LI> Cu interaction in tetragonal lattice of Cu<SUB>x</SUB>In<SUB>2-x</SUB>S<SUB>3</SUB> promotes surface induced charge transfer. </LI> <LI> Cu<SUB>x</SUB>In<SUB>2-x</SUB>S<SUB>3</SUB> diodes demonstrate improved conductivity/photoelectrical performance. </LI> <LI> Reproducible photo switching was studied along <I>p-n</I> CdTe/Cu<SUB>x</SUB>In<SUB>2-x</SUB>S<SUB>3</SUB> heterojunction. </LI> <LI> Cu<SUB>x</SUB>In<SUB>2-x</SUB>S<SUB>3</SUB> nanostructures exhibit excellent photocatalytic performance under visible light. </LI> </UL> </P>