Solar cells absorb incoming sunlight and convert a part of photon energy into electricity. The remainder of photon energy is dissipated as heat. Although the idea is rather counter-intuitive, 'reverse solar cell' systems can also generate electric power by emitting rather than absorbing photons. Such systems - known as thermoradiative cells - generate voltage and electric power via non-equilibrium thermal radiation of infrared photons. Thermoradiative cells offer an opportunity to generate clean energy by harvesting radiation from largely untapped terrestrial thermal emission sources, potentially including the Earth itself.
Newly developed nanocomposites possess efficient photothermic properties for highly targeted interfacial phase transition reactions that are synergistically favorable for seawater catalysis and desalination. The nanocomposites are seawater and photostable for practical solar conversion of seawater to simultaneously produce clean energy and water. This work defines the forefront of plasmonic photothermic technology, which is vastly untapped and has broad implications in other fields.
Although developed only recently, inorganic halide perovskite quantum dot systems have exhibited comparable and even better performances than traditional quantum dots in many fields. They are expected to be applied in display and lighting technologies. Researchers now have reported an interesting cyclable surface dissolution and recrystallization phenomenon of inorganic perovskite crystals. This allows them to freely change size between nanometer and micrometer scales, and can be used to healing the defects inside perovskite films and hence improve the performances of optoelectronic devices.
The development of perovskite solar cells, first reported in 2009 (and with a record power conversion efficiency of 20.1 percent so far), is a possible route towards high efficiency photovoltaics that are also cost-effectiveness, owing to to their easy-processing from solution. Question marks have however remained on their stability. Now, researchers report the world's first nanorod-based perovskite solar module. In addition to high efficiency, these perovskite solar modules also show remarkable and improved shelf life.
Researchers have integrated a biocompatible silk fibroin with a mesh of silver nanowires to achieve a flexible, transparent, and biodegradable substrate for efficient plastic solar cell. The most common flexible substrates used for flexible solar cells so far have been synthetic polymers such as PET and PEN. However, if organic solar cells are to be applied onto clothes and other soft surfaces, some of which come into direct contact with skin, they are required to be human-compatible, non-toxic and non-irritable.
In recent years, polymer solar cells have drawn considerable research interest due to their attractive features including flexibility, semi-transparency, and manufacturability using cost-effective continuous printing processes. However, one challenge limiting their commercialization is the relatively low power conversion efficiency when compared to inorganic solar cells. New work shows that low bandgap polymer solar cells with high efficiency of 5.5% can be fabricated using nanoimprint lithography.
A large part of low-energy photons, such as in the deep-red and infrared, are lost during conventional photovoltaic or photochemical processes. However, about half of all the solar energy reaching the Earth's surface can be found in these wavelengths.
Harvesting this light more efficiently is possible thanks to a process called photon energy upconversion. Researchers now have successfully synthesized a bioinspired upconverting solid-state-like film using nanocellulose.
Researchers present an efficient design for a triple-junction organic tandem solar cell featuring a configuration of bandgap energies designed to maximize the tandem photocurrent output. The key innovation in this study is the demonstration of organic materials being able to mimic the record-setting efficiency of triple-junction structures in III-V solar cells. The team set out to determine a practical combination of bandgap energies for triple junctions to develop an efficient organic tandem solar cell structure.