Search

In this work, ZnO/Ag(Cu doped)/ZnO and ZnO/(Cu doped) Ag/ZnO/SiO2 multilayer films are prepared on glass by a sputtering technique. The optical, structural, and morphological properties of the Ag-based multilayer structures are compared. According to the results of the transmittance curve, it is found that the Cu doping into Ag leads to a significant broadening of the transmittance spectrum of the multilayer. The performance of the multilayer largely depends on the deposition time of different films. After doping with copper, the average light transmittance of the multilayer film exceeds 81.2% from 380 to 1100 nm, and the average light transmittance exceeds 10.2% from 1100 to 2500 nm. When the SiO2 anti-reflection layers are introduced, the average light transmittance of the multilayer structure from 380 to 1100 nm exceeds 85.2%, and this value reaches 18.3% from 1100 to 2500 nm. In addition, a 6-inch ZnO/Ag(Cu doped)/ZnO/SiO2 multilayer is used as the cover layer of the silicon solar cell. After 2 h of sunlight exposure, the increase in working temperature is reduced by 12 °C while the open-circuit voltage reduction is reduced by 4.1% in comparison with that using standard glass. [ABSTRACT FROM AUTHOR]

Double-layer films of ZnO and antimony doped tin oxide (ATO) have great potential for application in photoelectric devices by the integration of the ultraviolet (UV) absorbance of the ZnO layer and the near-infrared (NIR) blocking and conductivity induced by the ATO film. Thus the nanostructure of ATO film on the surface of the ZnO layer plays an important role in determining the photoelectric property of ZnO/ATO bilayer film. In this work, ATO films are deposited on the ZnO layer by a radio frequency magnetron sputtering method and the structures and photoelectric properties, particularly the electric properties of ATO films on the ZnO layer are investigated by the regulation of gas flow ratio of O2/Ar and the sputtering power. After optimization of the conditions depositing ATO films on the ZnO layer, which is at an O2/Ar ratio of 2:13 with sputtering power of 150 W, ATO film shows a good conductivity of about 213.4 Scm−1 after annealing in nitrogen at 500 °C for 1 h. The double-layer film of 500 nm ATO film on 200 nm thick ZnO layer presents good optical properties with a high UV-blocking of 96% (280–380 nm), a NIR-blocking of 80% (1100–2500 nm) and light transmission of about 70% (380–1100 nm). [ABSTRACT FROM AUTHOR]

Magnetron co-sputtering method followed by selenization was used for the preparation of Cu2Zn(Sn,Ge)(S,Se)4 (CZTGeSSe) thin film. The impact of Ge doping layer with different sputtering times on crystalline quality, surface roughness, band structure and device performance of CZTGeSSe absorber was systematically investigated. It was found that the increased Ge/(Ge + Sn) ratio could effectively promote the grain growth and improve the band mismatching of CZTGeSSe/CdS interface. The CZTGeSSe thin film with minimum roughness and increased CBO (− 0.54 to − 0.41 eV) was obtained with the increased Ge/(Ge + Sn) ratio of 7.3%. However, oversized grain with rougher surface could result in a non-uniform coverage phenomenon of CdS layer, leading to severe interface recombination. After optimizing the Ge/(Ge + Sn) ratio, the best device performance with an efficiency of 3.19% was achieved in flexible CZTGeSSe thin film solar cells. [ABSTRACT FROM AUTHOR]

Phosphorus diffusion was used widely in mass production of p-type silicon solar cells. In order to improve the quality of P doped layer fabricated, a novel phosphorus source mixing phosphoric acid with SiO2 nanosphere was introduced. A high diffusion uniformity of 94.9% was obtained when SiO2 nanosphere was introduced while the uniformity of sample diffused without SiO2 nanosphere was 84.49%. It was found that the formation of dead layer could be avoided by introducing the SiO2 nanosphere, as observed by SEM images, and the minority carrier lifetime of sample was enhanced by 27.87 µs. The surface sheet resistance decreased from 132.62 to 12.8 Ω/□ with the increase of temperature from 825 to 925 °C. Through an etching method, a variation of junction depth increasing from 300 to 571 nm was found with increasing temperature. The variation trends of surface sheet resistance and junction depth with the increase of time were similar with that of temperature. [ABSTRACT FROM AUTHOR]

NaY(WO4)2: Er3+ phosphors with various doping concentrations of [Er3+]/([Er3+]+[Y3+]) (0, 5, 7, 10, 12, 15%) were successfully synthesized by high-temperature solid-state reaction. X-ray diffraction (XRD) measurement demonstrated the presence of tetragonal-phase NaY(WO4)2 phosphors and Fourier transform infrared (FT-IR) spectra showed a strong υ3 stretching vibration mode of WO42−, indicating the good crystallization of the phosphors. Well-crystallized phosphors showed a fine morphology with particle sizes of 0.8-10 µm by scanning electron microscope (SEM). Under excitation of 980 nm laser, Er3+-doped phosphors exhibited strong green emissions centered at 527 and 549 nm in addition to a 665 nm emission band in the red region, which were assigned to the 2H11/2, 4S3/2 → 4I15/2 and 4F9/2 → 4I15/2 transitions, respectively. When the doping concentration was 10%, the intensities of green and red emissions reached their maximum values, stronger than that in 5% Er3+ doped one by 13 times. The double-logarithm plot of the upconversion (UC) emission intensity to the excitation power for different Er3+ doping concentrations depicted that at least two infrared photons were involved for every emitted green and red photon. UC emission intensity changing with temperature displayed different trends for the phosphors with different Er3+ concentrations. The enhancement for green emission band centered on 549 nm could reach 50 times at 30 K in sample with 5% Er3+ concentration. Under excitation by 355 nm laser, all the phosphors showed a strong PL emission band at 430 nm, while green luminescence band locating from 540 to 570 nm was only observed in 7, 10, and 12% Er3+-doped phosphors, which was ascribed to 4S3/2 → 4I15/2 transition. [ABSTRACT FROM AUTHOR]