Browsing all articles tagged with solar cells

Quantum entanglement in real biological system

green plantsThe future of clean green solar power may well hinge on scientists being able to unravel the mysteries of photosynthesis, the process by which green plants convert sunlight into electrochemical energy. To this end, researchers at the Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UC) have recorded the first observation and characterization of a critical physical phenomenon behind photosynthesis known as quantum entanglement.

Previous experiments led by Graham Fleming, a physical chemist, pointed to quantum mechanical effects as the key to the ability of green plants, through photosynthesis, to almost instantaneously transfer solar energy from molecules in light harvesting complexes to molecules in electrochemical reaction centres. Now a new collaborative team that includes Fleming have identified entanglement as a natural feature of these quantum effects. Their work is published in the Nature Physics journal. When two quantum-sized particles, for example a pair of electrons, are entangled, any change to one will be instantly reflected in the other, no matter how far apart they might be. Though physically separated, the two particles act as a single entity.

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New prospects for solar cells

new solar cellsThe most efficient solar cells, composed of a semiconductor material such as silicon, have been developed in Switzerland in the early 90s. As in the case of conventional electrochemical batteries, solar cells consist of a cathode, a platinum-based catalyst, and an anode, a porous layer formed from titanium dioxide nanoparticles and coated with a dye absorbs sunlight. A conductive liquid, the electrolyte is placed between two electrodes.

Despite the use of materials for the most inexpensive, easy to manufacture and flexible, large-scale commercialization of these batteries confronts two major obstacles. The electrolyte is very corrosive, causing a deficiency in sustainability. It is also very colorful, preventing light from entering and effectively limiting the photo-voltage of 0.7 volts. Moreover, platinum is an expensive material, non-transparent and rare.

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