A hybrid receiver composed of a concentrator photovoltaic (CPV) module and a thermal receiver is developed for a photovoltaic-solar thermal (CPV/T) cogeneration system. The receiver has the appearance of a flower and is referred to as a sunflower receiver. The unique nature of this design uses both waste heat from the CPV cells and intentional spillage of a large fraction of the concentrated solar energy to generate very high temperature thermal output (up to 250°C) from a single heat transfer fluid, while the temperature of the cells is maintained below 110°C as they convert part of the solar spectrum into electricity. The exit temperature of the heat transfer fluid is adjustable according to the requirements of commercial or industrial process heat application. Early prototype results are discussed.

A spectrum-splitting photovoltaic module is developed for hybrid photovoltaic-solar thermal energy conversion using direct fluid cooling (DFC) of partially transmissive concentrator photovoltaic cells. The waste heat generated in photovoltaic cells can be more efficiently extracted by flowing a heat transfer fluid in direct contact with both sides of the cells. The module also acts as a beam splitter, dividing the incident light into two parts. Photons with higher energy than the bandgap of the cells are absorbed in cells, while photons with lower energy are passed through the infrared-transmissive module to a thermal receiver. Optical modeling (experimental) shows 63.2% (34.3%) out-of-band transmittance through the cell regions and 90.4% (89.0%) full spectrum transmittance through the surrounding bypass region. Thermal modelling verifies the direct cooling fluid method is an effective way to maintain cell temperature <; 110°C. Electrical power conversion efficiency in a first prototype module is 79% of the bare cell efficiency. Fluid flow characterization shows laminar flow. The modules are currently undergoing field testing.

Two-dimensional semiconductors, such as MoS2, are leading candidates for the production of next-generation optoelectronic devices such as ultrathin photodetectors and photovoltaics. However, the commercial application of 2D semiconductors is hindered by growth techniques requiring hours of heating and cooling cycles to produce large-area 2D materials. We present here a growth technique that leverages high-intensity optical irradiation of a solution-processed (NH4)2MoS4 precursor to synthesize MoS2 in one-tenth the time of typical furnace-based CVD. From start to finish, the technique produces uniform 2D MoS2 across 4-in. wafers within 15 min. Raman spectroscopy, in-plane XRD, and XPS show a 2H MoS2 crystal structure with a stoichiometry of 1.8:1 S:Mo. AFM scans show that the films are 2.0 nm thick MoS2 with a roughness of 0.68 nm. Photoluminescence spectroscopy reveals the characteristic 1.85 eV bandgap. The as-grown films were used to make field-effect transistors with a mobility of 0.022 cm2 V−1 s−1 and photodetectors with a responsivity of 300 mA/W and an external quantum efficiency of 0.016%, demonstrating their potential for optoelectronic device development. This rapid thermal processing growth technique reduces MoS2 synthesis time by an order of magnitude relative to comparable techniques and enables greater accessibility to 2D semiconductors for researchers and developers.