Swiss Federal Institute of Technology in Lausanne, Photonics and interfaces laboratory chemist by Professor Michael Guerra Hazel photoelectric led scientists to mimic plant photosynthesis invented dye-sensitized solar cells, they also developed the decomposition of water by the sun such as hydrogen and other fuels.
Beijing time on September 29 message, the Science Daily reported, and now scientists are looking for ways to optimize the amount of solar energy. Silicon photovoltaic electricity panels, dye-sensitized solar cells, solar panels and concentrated solar thermal power plants are pursuing the same goal: To get the maximum amount of electrons from sunlight. These electrons can be converted into electricity, lighting and provide energy for the realization of the refrigerator and other purposes.
Swiss Federal Institute of Technology in Lausanne (EPFL) Laboratory of Photonics and interface, by photoelectric chemist Michael Guerra Hazelle (Michael Gr? Tzel) scientists led by Professor mimic plant photosynthesis invented dye-sensitized solar cells, they also developed the decomposition of water by the sun and other fuels such as hydrogen.
To achieve this, they either have to use the exposure to sunlight can split water into hydrogen and oxygen directly photocatalytic hydrogen batteries, or they will combine battery power and decomposition of water molecules in the electrolyser. By using the second method, Glasgow Hazel PhD student Luo Jingshan (Jingshan Luo) and his colleagues received a surprising result, this achievement has been published in the journal “Science”. Perovskite solar panel, 12.3% of their equipment will diffuse solar energy is converted to hydrogen, the compounds of this material in the laboratory can be obtained by conventional, such as those used in the conventional materials in a car battery, thereby reducing for the production of hydrogen fuel needed to use the rare earth metals.
This efficiency leads to fierce competition exists between other solar energy conversion technologies, but this latest method there are other advantages: “perovskite battery in use, as well as a catalyst composed of nickel and iron electrodes, what is needed is the Earth and inexpensive resources abound, “Luo explained. “In addition, we often use the performance of the electrode and the more expensive platinum based on the model as well.”
On the other hand, the conversion of solar energy to hydrogen so that it becomes possible to store, it emphasizes one of the biggest problems faced by the renewable power – generating the request when it must be used. “Once you have hydrogen, you can store it in a bottle and use when you need to,” Graham said Hazel. This gas can indeed burning in a boiler or engine, and it will only produce water vapor. It can be placed in the fuel cell and generate the required power. Currently 12.3% conversion efficiency of the Swiss Federal Institute of Technology in Lausanne, obtained “in the future will be higher,” Guerra said Hazel.
Such a high conversion efficiency is based on a characteristic of the perovskite cell: they produce an open circuit voltage greater than one volt (silicon cell can produce compared to 0.7 volts). “Electrolysis requires even higher voltage 1.7 volts, which can be used to get gas,” Luo said. To achieve this goal, at least three or more silicon cells, however, requires the use of only the perovskite cell 2. Therefore, consideration of the desired light absorption surface, the higher the efficiency of the perovskite cell. “This is our first time using only two batteries can obtain hydrogen by electrolysis.” When the solar cell is exposed to sunlight, and soon electrode produces a large number of bubbles, the facts speak for themselves: the combination of sun and water indicates that R & D energy future very promising and very exciting new ways.