Sulfide Thin-film Solar Cells Research Articles

Silver sulfide thin film solar cells: materials, fabrication methods, devices, and challenges

This review summarizes the current research status on fabrication methods, device structure selection, design and optimization of Ag2S thin films. Insights into achieving high-efficiency Ag2S devices by improving the crystallinity of the absorber layer and reducing interface defects are discussed.

Self-assembled Nanometer-Scale ZnS Structure at the CZTS/ZnCdS Heterointerface for High-Efficiency Wide Band Gap Cu2ZnSnS4 Solar Cells

Despite remarkable progress in the performance of kesterite Cu2ZnSnS4 (CZTS)-based photovoltaic technology has been achieved, the interface recombination and associated open-circuit voltage (Voc) deficit still dominate the loss mechanism in this technology. To alleviate heterojunction interface recombination in pure sulfide thin film solar cells, passivation structure at the interface is required. In this work, we developed an ultrathin nanometer-scale ZnS dielectric passivation layer which is readily formed in situ at the CZTS/ZnCdS heterointerface during the ZnCdS buffer deposition process via Zn diffusion from the ZnCdS bulk to the interface. With this nanoscale structure, a remarkable open-circuit voltage and fill factor improvement is illustrated, and a total area efficiency of 9.25% is obtained. The formation and features of the nanoscale ZnS layer are investigated by high-resolution scanning transmission electron microscopy and energy-dispersive X-ray spectroscopy. This self-assembled ZnS layer wit...

Stable Performance of Chemically Deposited Antimony Sulfide-Lead Sulfide Thin Film Solar Cells under Concentrated Sunlight

Thin film solar cells of FTO/CdS/Sb2S3/C-Ag or FTO/CdS/Sb2S3/PbS/C-Ag prepared via chemical deposition of thin films of CdS (100 nm), Sb2S3 (200 - 400 nm) and PbS (110 or 220 nm) on transparent conductive oxide of SnO2:F (FTO) are presented. These cells are stable under concentrated sunlight of intensity of up to 10 kW/m2. The optical bandgap of Sb2S3 thin films is 1.57-1.83 eV and of the PbS thin film, 1.03-1.40 eV. The photoconductivity of Sb2S3 is 5.8 × 10−7 Ω−1 cm−1(n-type); of PbS thin films it is 10−2 Ω−1 cm−1 (p-type); and of CdS film it is 2 × 10−3 Ω−1 cm−1. The addition of PbS thin film in the cells notably improves the open circuit voltage (Voc), short circuit current (Jsc) as well as the energy conversion efficiency (η) of these cells. Under sunlight, Voc is 438 mV, Jsc is 1.38 mA/cm2 and η is 0.12% for a FTO/CdS/Sb2S3(400 nm)/C-Ag cell; and 578 mV, 8.61 mA/cm2 and 1.34%, for a FTO/CdS/Sb2S3(400 nm)/PbS(220 nm)/C-Ag cell. Under 4 kW/m2, Voc is 581 mV, Jsc is 3.55 mA/cm2 and η is 0.10% for the FTO/CdS/Sb2S3(400 nm)/C-Ag cell; and 611 mV, 23.54 mA/cm2 and 0.89%, respectively, for the FTO/CdS/Sb2S3 (400 nm)/PbS(220 nm)/C-Ag cell. Through the measurement methodology described for evaluating the performance of the cells, we establish that these cells remain stable under concentrated as well as steady-state solar radiation.

Photovoltaic solar arrays for communication satellites

Photovoltaic solar arrays are the principal means of converting solar energy to electrical energy for satellites. Array configurations depend on the spacecraft stabilization concept, orbit, and power requirements. The current generation of communication satellites are spin-stabilized in synchronous equatorial orbits; their arrays are spinning cylinders. As satellite power requirements increase, it is expected that the trend will be toward extendible arrays on three-axis stabilized spacecraft. The single crystal silicon cell is the basic building block of today's solar arrays and is expected to be for some time, although cadmium sulfide thin film solar cells may offer several advantages once their development is completed. Several of the considerations in the design of solar arrays are discussed: radiation effects on solar cells, substrates, selection of array voltage, analysis of shadows, and overall performance.

Performance of cadmium sulfide thin film solar cells in a space environment

Cadmium sulfide thin film solar cells have been subjected to extended thermal cycling tests in vacuum to simulate the conditions of an earth orbiting satellite. When cycled under load, the solar cells exhibit a slow loss of output. Several possible causes of this loss are suggested.