Search

A tandem solid-state dye-sensitized solar cell (SSDSC) without color distortion for potential photovoltaic window applications is reported. The bifacial tandem SSDSC with two spectrally complementary sensitizers using parallel-connection is realized, which leads to non-color distortion. The Commission Internationale de l'Eclairage (CIE) chromaticity diagram is applied to verify the extent of color distortion. At this circumstance, the photovoltaic performance for the tandem SSDSC with a power conversion efficiency of 3.3% was achieved under AM 1.5G, 100 mW/cm2 illumination. The overall efficiency in the tandem architecture outperformed each individual cell. Our results demonstrate the feasibility for visible light transmission, non-color distortion, power-generating windows for application in building-integrated photovoltaics (BIPV). Moreover, this tandem SSDSC architecture has potential for the integration into window curtains application due to its flexible characteristics. With further extension of the absorber spectrum into the IR region, a better solid-state tandem DSC is expected.

A diffusive solar cell window comprises a diffusion plate with TiO2nanoparticles sandwiched between two glass layers. It is a simple, inexpensive, easy-to-made, and highly reliable transparent solar energy module. To improve its power generation efficiency as well as maintain indoor natural lighting, we examined the scattering mechanism in the diffusion plate with TiO2nanoparticles within a diffusive solar cell window by Mie scattering simulations. In this work, a multiwavelength ASAP ray tracing model for a diffusive solar cell window with acceptable accuracy was developed to investigate the influence of the diffusion plate design parameter, mainly concentration of a diffusion plate with determined particle size distribution, on power generation efficiency and color shift of transmitted sun light. A concept of “effective average radius” was proposed to account for the equivalent scattering effect of a size distribution of quasispherical particles. Simulation results demonstrated that both the transmitted light and its correlated color temperature decreased as the concentration increased for a large-size diffusive solar cell window. However, there existed a maximum power generation efficiency at around 160 ppm concentration. The optimal design for a large-size diffusion plate inside a diffusive solar cell window by taking indoor lighting into account was suggested based on the simulation results.

This study reports the fabrication of efficient deep blue-emissive polymer light-emitting diodes (PLEDs), incorporating a polyfluorene derivative of nonsymmetric and bulky aromatic groups at C-9 position as the light-emissive layer. Another poly(fluorene- co -triphenylamine) (PFO-TPA) derivative of the highest occupied molecular orbital level, −5.3 eV, is used as the hole-injection and -transport layer in the anode part. The thermally crosslinking of styryl groups in PFO-TPA inhibits the solvation of an interlayer in constructing the multilayer device architecture of PLEDs. While applying a cesium carbonate (Cs 2 CO 3 )/Aluminum (Al) cathode rather than Calcium (Ca)/Al, the device has the superior performance (i.e. one order of magnitude higher). Experimental results indicate that the interfacial reactions at the polymer/Ca junction, as characterized in this study, significantly degrade the luminescence properties and the device performance. Moreover, Cs 2 CO 3 /Al is a highly favorable cathode in fabricating polyflourene-based PLEDs. The device of the optimal configuration has a decent deep blue emission centered at 430–450 nm of the Commission Internationale de l’Eclairage chromaticity coordinates, (0.15, 0.14), with a maximum brightness of 35054.2 cd/m 2 and luminous efficiency of 14.0 cd/A (at 2975.0 cd/m 2 ).

A diffusive solar cell window was designed and fabricated with uniformly distributed nanocomposite particles in a light diffusive plate that was sandwiched between two glass layers. The entire composite construction transfers light radiation to solar cells at the edge of the windows. It is based on a new combination of existing technologies because of it uses mature, mass-produced components - solar cells - as well as nanocomposite particles that are embedded inside the light-guide plate. They are integrated using an inexpensive and widely used method for making building windows. The result is an inexpensive, strong, stable, view quality-preserving solar energy-harvesting window that has no close competition. The diffusive solar cell window does not suffer from aging, and products that are made using diffusive solar cell window technology will be new entries to the solar power generation window market.

A transparent solar cell window module based on the integration of traditional silicon solar cells and organic–inorganic nanocomposite material was designed and fabricated. The transparent solar cell window module was composed of a nanocomposite light-guide plate and traditional silicon solar cells. The preparation of the nanocomposite light-guide plate is easy without modification of the traditional casting process, the nanoparticles sol can be added directly to the polymethyl methacrylate (PMMA) monomer syrup during the process. The solar energy collected by this window can be used to power up small household electrical appliances.

A yellow flexible top-emission polymer light-emitting diode (TOPLED) was fabricated on cyclic olefin copolymer (COC) substrate. The light-emitting material was phenyl-substituted (p-phenylene vinylene) (HYPPV) polymer. The structure of TOPLED was COC/Ag/PEDOT:PSS/HYPPV/Ca/Ag. The Ag on COC was used as anode and the Ag on Ca was used as cathode. After anode Ag was thermally evaporated on COC substrate, the ultraviolet-ozone (UV-ozone) was treated on surface of anode Ag. The treating time was varied. The optimal treated time was 3 minutes. The luminous efficiency of TOPLED increased 42% with 3 minutes UV-ozone treatment.

Building integrated photovoltaics (BIPV) are an important application of future solar energy development. The incorporation of solar cells into windows must not only maintain indoor natural lighting but also generate electrical power at the same time. In our continuing effort to improve the design of diffusion solar window, a more fundamental and efficient three-layer structure—glass/EVA with TiO2nanoparticles embedded/glass—was proposed. In this work, a well-established ASAP ray-tracing model for a diffusive solar cell window was implemented to validate the outperformance of three-layer structure over primitive five-layer structure. Optical simulations were also implemented to perform its primary design for the determination of the optimal design parameters, such as the glass thickness, the EVA thickness, and the weight concentration of TiO2nanoparticles. Based on the simulation results, an optimal design for a three-layer diffusive solar cell window prototype was proposed. And the influence of both EVA thickness and glass thickness on the power edge-exitance (solar cell power generation efficiency) of a DSCW was thoroughly investigated.

A more efficient OLED device with blue emission characteristic of terfluorene has been achieved by using a novel molecular doping strategy, in which 4,5-diazafluorene was incorporated as the substitution group of terfluorene to facilitate electron injection from the metal cathode yet without altering emission characteristics.

In this paper, we added CdSe/ZnS core/shell quantum dots (QDs) into anthracene-contained polymer. The photoluminescent (PL) characteristic of polymer/QD composite film could identify the energy transitions of anthracene-contained polymer and QDs. Furthermore, the electroluminescent (EL) characteristic of hybrid LED also identifies emission peaks of blue polymer and QDs. The maximum luminescence of the device is 970 cd/m(2) with 9.1 wt.% QD hybrid emitter. The maximum luminous efficiency is 2.08 cd/A for the same device.