At present, localized surface plasmon resonance (LSPR) is considered one of the most promising strategies for controlling surface chemistry with hot charge carriers4,5,6. LSPR is the collective oscillation of metal electrons that can be excited by incident light at the interface between a metal nanoparticle and a dielectric (or semiconductor) environment. During decay, LSPR can generate a significant flux of hot electrons and holes with excess energies of several electron volts. In clean metals, plasmon-induced charge carriers can be injected into the adsorbate to drive a photochemical reaction or they disappear as a result of thermalization (Fig. 1a). To reduce the recombination rate of the hot carriers and thereby increase the efficiency of the metal nanoparticles as catalysts, a Schottky contact can be used, which is created by depositing metal nanoparticles on a semiconductor surface7,8,9,10,11. Much work has been done studying plasmon-induced reactions of various types ranging from the simplest dissociation of molecules4,12 to more complex surface reactions13,14,15,16,17,18,19,20. In particular, a number of studies14,21,22,23,24,25 have shown a significant improvement in the efficiency of different catalysts for the hydrogen evolution reaction (HER) caused by the generation and transfer of hot electrons. A more detailed review of hot-electron-driven chemistry can be found in a recent paper by Wei and co-workers7. However, because of its complexity, the detailed mechanism for energy transfer from a plasmonic nanoparticle to a chemisorbed molecule remains poorly understood15,26. The task is further complicated by the fact that catalysts based on LSPR are often multicomponent core-shell or antenna-like nanostructures containing both plasmonic and catalytic materials15,27. The properties of such nanostructures can change over the course of a photocatalytic reaction because of the presence of adsorbates26,28,29. Therefore, further progress in studying the chemistry of hot-charge carriers requires the development of new research methods that include these factors.
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In this paper, Schottky diodes (SDs) obtained by evaporated thin films of aluminum on pulverized p-CuInS2/SnO2:F have been studied using J-V-T characteristics in a temperature range of 200-340K. These characteristics show that aluminum acts as a rectifier metal-semiconductor contact. Characteristic variables of the Al/p-CuInS2/SnO2:F junctions, such as the current density, the serial resistance, the parallel conductance, the Schottky barrier height (SBH), and the ideality factor of the SD were obtained by fitting the J-V-T data using the Lambert function. Data analysis was conducted with the use of MATLAB. Results showed that n is greater than 1, which could be explained by the existence of inhomogeneities due to the grain boundaries in CuInS2. Through this analysis, one can see a good agreement between experimental and modeled data. The study has shown that the main contribution in the current conduction in such heterostructures is the thermionic emission (TE) supported by the recombination of the carriers. The last phenomenon appears mainly in the grain boundaries, which contain both intrinsic and extrinsic defects (secondary phases, segregated oxygen). An investigation of the J-V-T characteristics according to TE theory has demonstrated that the current density and the SBH increase while serial resistance, parallel conductance decrease with an increase in temperature. After an SBH inhomogeneity correction, the modified Richardson constant and the mean barrier height were found to be 120AK-2cm-2 and 1.29eV respectively. This kind of behavior has been observed in many metal-semiconductor contacts. 2ff7e9595c
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