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Carbon-based composite conductive ink (3CI) has some challenges to its properties. Here, combined with the application of 3CI on silicon keypads, a series of studies on the electrical, mechanical and thermal performance of 3CI has been conducted by adding specific concentrations of silver powder, silica powder and SiO2@Ag core-shell particles. The properties of the modified 3CI were characterized by using the four-point probe tester, scanning electron microscope, Rockwell hardness tester, cross-cut tester and laser thermal conductivity analyzer. The experimental results revealed that by adding silver powder with a particle size of 20 microns equivalent to 12% by weight of the 3CI, ink resistance decreased by 76%, from 8.44 kΩ/□ to 2.03 kΩ/□. Meanwhile, adding silica can increase the ink's tensile strength and thermal diffusivity while improving the adhesion of the 3CI on the silicone rubber. It was worth noting that when the particle size of the SiO2@Ag core-shell particle was smaller than that of the added silver powder, the resistance of the 3CI was further reduced. Finally, a modified 3CI with the adhesion of 4B, a conductivity of about1 kΩ/□, a hardness of 232 HV0.5, and a thermal diffusivity of 0.217 cm2s−1 was achieved experimentally, which provided an experimental basis for the modified 3CI suitable for silicone keypads. [ABSTRACT FROM AUTHOR]

The application of thinner cadmium sulfide (CdS) window layer is a feasible approach to improve the performance of cadmium telluride (CdTe) thin film solar cells. However, the reduction of compactness and continuity of thinner CdS always deteriorates the device performance. In this work, transparent Al2O3 films with different thicknesses, deposited by using atomic layer deposition (ALD), were utilized as buffer layers between the front electrode transparent conductive oxide (TCO) and CdS layers to solve this problem, and then, thin-film solar cells with a structure of TCO/Al2O3/CdS/CdTe/BC/Ni were fabricated. The characteristics of the ALD-Al2O3 films were studied by UV–visible transmittance spectrum, Raman spectroscopy, and atomic force microscopy (AFM). The light and dark J–V performances of solar cells were also measured by specific instrumentations. The transmittance measurement conducted on the TCO/Al2O3 films verified that the transmittance of TCO/Al2O3 were comparable to that of single TCO layer, meaning that no extra absorption loss occurred when Al2O3 buffer layers were introduced into cells. Furthermore, due to the advantages of the ALD method, the ALD-Al2O3 buffer layers formed an extremely continuous and uniform coverage on the substrates to effectively fill and block the tiny leakage channels in CdS/CdTe polycrystalline films and improve the characteristics of the interface between TCO and CdS. However, as the thickness of alumina increased, the negative effects of cells were gradually exposed, especially the increase of the series resistance (Rs) and the more serious "roll-over" phenomenon. Finally, the cell conversion efficiency (η) of more than 13.0% accompanied by optimized uniformity performances was successfully achieved corresponding to the 10 nm thick ALD-Al2O3 thin film. [ABSTRACT FROM AUTHOR]

Aluminum antimony (AlSb) is a promising photovoltaic material with a band gap of about 1.62 eV. However, AlSb is highly deliquescent and not stable, which has brought great difficulties to the applications. Based on the above situation, there are two purposes for preparing our Zn-doped AlSb (AlSb:Zn) thin films: One is to make P-type AlSb and the other is to find a way to suppress the deliquescence of AlSb. The AlSb:Zn thin films were prepared on glass substrates at different substrate temperatures by using the pulsed laser deposition (PLD) method. The structural, surface morphological, optical, and electrical properties of AlSb:Zn films were investigated. The crystallization of AlSb:Zn thin films was enhanced and the electrical resistivity decreased as the substrate temperature increased. The scanning electron microscopy (SEM) images indicated that the grain sizes became bigger as the substrate temperatures increased. The Raman vibration mode AlSb:Zn films were located at ~107 and ~142 cm−1 and the intensity of Raman peaks was stronger at higher substrate temperatures. In the experiment, a reduced band gap (1.4 eV) of the AlSb:Zn thin film was observed compared to the undoped AlSb films, which were more suitable for thin-film solar cells. Zn doping could reduce the deliquescent speed of AlSb thin films. The fabricated heterojunction device showed the good rectification behavior, which indicated the PN junction formation. The obvious photovoltaic effect has been observed in an FTO/ZnS/AlSb:Zn/Au device. [ABSTRACT FROM AUTHOR]