Development and production of dye-sensitized solar cells

Development and production of dye-sensitized solar cells

Research funded by the U.S. Research Science and Technology Fund advances innovation at Solar Power. This innovative green dye solar cell is expected to cut production costs by 90% compared to conventional silicon-based solar cells, and can work efficiently in low light conditions, even on cloudy days. Photosensitive dye solar cells are 20.

Since the beginning of the 1970s, the application of silicon-based solar cells has been another new approach in the field of solar energy utilization. Green makes the photosynthetic efficiency of leaves reach 30% to 40%, and the green dye used to make new solar photovoltaic facilities is synthetic chlorophyll obtained from light plants. The dye molecules coat fine metal oxide particles, which are fused in the thin film. Green dye molecules capture light energy in the spectrum and release electrons, and the particles act like electronic nanowires, which transport electrons into circuits. The metal used in this solar cell is titanium dioxide, an abundant, nontoxic, white mineral that has applications in many consumer products and even toothpaste and cosmetics. The first green dye solar cells were introduced in 2008. click here to open to learn more about batteries with us.

Researchers at Ohio State University in the United States have developed a new technology that uses solar energy, and a pale yellow pigment is expected to become a new technology for greening. Scientists are said to have developed new photosensitive dye solar cells, which are made from a mixture of red dyes and white metal oxide powders to produce pale yellow materials that trap light. This new class of yellowish-colored materials is now half as efficient at converting light into electricity as commercial silicon-based solar cells, but at a quarter of the cost of light-sensitive dye solar cells, the researchers believe. The efficiency will reach levels comparable to that of any solar cell in the future. The main advantage of DSSC is its low cost, which is also the charm of speeding up research. Pale yellow is a typical color of DSSC. Most of the nail-containing dyes used are red pigments, and the metal oxide powders are mostly a mixture of titanium oxide or zinc oxide, both of which are white.

However, the materials developed by the researchers are novel materials that use a variety of metals and are made into different particle shapes to increase the amount of electricity generated. Traditional solar cells look blue because of the use of anti-reflective coatings. The coating increases the absorption of green light, the strongest light in the solar spectrum. The materials studied above did not contain antireflection coatings. British scientists led by Durham University announced in mid-January 2008 the launch of one of the UK’s largest research projects to study new materials for photovoltaic solar energy. The $12.3 million, four-year “PV-21” research program focuses on the fabrication of thin-film light-absorbing cells from sustainably available and economical materials for use in solar panels. Launched in April 2008, the project involves researchers from eight UK universities (Durham, Bangor, Bath, Cranfie1d, Edinburgh, Northumbria, Southampton and Imperial College London). Together with 9 industrial partners, these scientists will conduct mid- to long-term research on the utilization of solar energy with better competitiveness and sustainable availability. Currently, solar cells are made of some key components such as rare earth metal steel, which is priced at about 300 USD/lb. To reduce costs, the researchers will investigate reducing the thickness of the battery. Researchers will also use nanotechnology and dyes on ultrathin silicon to harvest more energy from sunlight. The project is funded by the UK Engineering and Physical Sciences Research Council.

Chinese scientists announced at the end of March 2008 that the conversion efficiency of solvent-free dye-sensitized solar cells exceeded 8.2%. This efficiency has broken through the absence of volatile organic solvents, so that dye-sensitized solar cells can be mass-produced and light-weight. , Inexpensive, flexible dye-sensitized solar cell thin films put into practical applications.

Dye-sensitized solar cells adapt to different lighting conditions
Dye-sensitized solar cells adapt to different lighting conditions

Wang Peng, a researcher from the State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, and Swiss scientists have made important progress in the research of dye-sensitized solar cells. The relevant results were published online on June 29, 2008 in the internationally renowned In the scientific journal Nature Materials, the current power conversion efficiency of dye-sensitized solar cells has reached 11.1% under the air mass 1.5G test condition, but this device uses highly volatile and highly toxic acetonitrile electrolyte, which greatly hinders the its utilisation process. Non-volatile room temperature ionic liquids provide an important solution to this problem, but the efficiency of the obtained devices is not high enough due to the high viscosity of ionic liquids. Wang Peng and his collaborators achieved room temperature ionic liquids by mixing a variety of solid salts to achieve the time-increase of the solid-liquid phase transition of the system (China Patent Application No.: 200710306662.1). This eutectic salt concept greatly broadens the material options for room temperature ionic liquids.

More importantly, liquid eutectic salts based on these high-lattice-energy solid-state ionic materials have lower viscosity and higher electrical conductivity than conventional room-temperature ionic liquids. The power conversion efficiency of solar cells prepared with eutectic room temperature ionic liquids reached 8.2%, setting a new world record for solvent-free dye-sensitized solar cells. The device showed excellent stability under accelerated aging test conditions. They also corrected the classical Stokes-Einstein equation by correlating ion mobility with system viscosity, clarifying that the transport of triiodide in ionic liquids involves physical diffusion coupled with electron exchange in addition to traditional physical diffusion Mechanisms. Additionally, they observed for the first time that electron transport in mesoporous conductors is affected by cation relaxation.

This research will greatly promote the commercialization of flexible dye-sensitized solar cells and provide new energy for portable electronic devices (such as mobile phones, walkmans, digital cameras, notebook computers, etc.) meaningful work”.

After more than three years of experiments and explorations, researchers from East China Normal University have successfully fabricated artificial “chloroplasts”, namely dye-sensitized solar cells, using nanomaterials in the laboratory, realizing low-cost photoelectric power generation. With the support of the Shanghai Nano Special Fund, the photoelectric conversion efficiency of bionic solar cells has exceeded 10%, which is close to the world’s highest level of 11%. According to reports, this new type of solar cell has a “sandwich” structure, in which a layer of nanometer “sandwich” is sandwiched between insulating glass. The “sandwich” formula functions as the dye as a light catcher, while the nano-titanium dioxide acts as a photoelectric converter.

As the third generation of solar cells, dye-sensitized cells are characterized by cheap raw materials and simple fabrication processes. It is estimated that the cost of dye-sensitized cells is only 1/10 of that of silicon panels. At the same time, it does not require high lighting conditions, and its photoelectric conversion rate will not be greatly affected even in a room with insufficient sunlight. . In addition, it can be used for a variety of purposes, such as replacing glass “plywood” with plastic, which can be used to make bendable and flexible batteries. It can be made into a display, which can generate electricity and emit light at the same time, so as to achieve energy self-sufficiency. It is understood that in order to promote the large-scale application of dye-sensitized solar cells, it is also necessary to solve the problems such as the reduction of cell efficiency with the enlargement of the area and the prolongation of service life.

Shanghai Jiao Tong University stated in February 2009 that the research on dye-sensitized solar cells by researchers at the school inspired by butterfly wings provides innovative thinking and realization possibilities for solving bottlenecks such as solar cell photoelectric conversion efficiency. Inspired by the structure of butterfly wings, the Legacy Materials Research Group of the School of Materials Science and Engineering, Shanghai Jiaotong University designed a new photoanode component for solar cells with high light harvesting efficiency, and conducted research and verification. The scientific research team is the first in the world to propose that TiO2 light harvesting devices for dye-sensitized solar cells can be prepared by using finely graded spiral fins as templates. Compared with ordinary TiO2 thin films, the light absorption rate of TiO2 with butterfly-fin structure can be increased by more than 2 times. Using this as a photoanode can greatly improve the light collection efficiency, which is expected to improve the photoelectric conversion efficiency of such solar cells. Following silicon-based solar cells, dye-sensitized cells have attracted much attention due to their low cost and green preparation process. However, problems such as low photoelectric conversion efficiency of dye-sensitized cells hinder their wide application. The material and structure of efficient sunlight harvesting ability have become a difficult problem for scientists from all over the world.

The Changchun Institute of Applied Chemistry, Chinese Academy of Sciences announced at the end of March 2009 that important progress has been made in the research of organic dye-sensitized solar cells, and an organic dye C217 with high absorption coefficient has been developed. The dye is used in devices using acetonitrile as the electrolyte solvent. A photoelectric conversion efficiency of 9.8% is achieved in the solar cell; combined with a solvent-free ionic liquid electrolyte, a long-term photothermally stable dye-sensitized solar cell with a photoelectric conversion efficiency of 8.1% can be produced. These two indicators represent the best performance of organic dye-sensitized solar cells. Its properties are already very close to nail dyes. This research achievement will further promote the development and application of pure organic dye-sensitized solar cells with broad spectrum, high efficiency and low cost.

The Changchun Institute of Applied Chemistry of the Chinese Academy of Sciences announced on April 16, 2009 that it has developed a cheaper and more efficient dye-sensitized solar cell (DSSC) by modifying the dye composition. The cost of dye-sensitized solar cells is lower than that of traditional silicon solar cells. , and are easier to print on soft surfaces, but making these kinds of high-efficiency batteries requires dyes made from precious metal pegs and volatile electrolytes.

Dye-sensitized solar cells (DSSCs) are very likely to be used in unmanned aircraft in the next few years due to their good photoelectric conversion efficiency and good scalability. , so that the aircraft can fly longer without refueling. Dr. Staia of the University of Washington’s Multidisciplinary Research Unit (MURI) is conducting research on transparent flexible solar cells for aircraft applications. According to reports, DSSCs have a different structure from conventional silicon-based solar cells in that the dyes on the nanosemiconductor surface can capture photons and convert them into electrons.

This solar cell has better photoelectric conversion efficiency and good expansion performance, and is easier to promote in terms of price. The team used the technique on the wing of a toy plane a few years ago. The solar cell successfully drove the propeller of the toy plane, but the glass base was too heavy to complete the take-off. After many experiments, the researchers finally adopted the thin-film battery technology, and the test plane using the light-weight thin-film solar cell finally flew successfully. Currently, the group is working to develop larger-area, more efficient, and more flexible DSSCs coatings for use on U.S. Air Force unmanned aircraft. But generally speaking, as the area increases, the conversion efficiency of solar cells will gradually decay. To solve this problem, the team used a metal grid technology that changes the resistance of the surface of the solar cell’s thin film and accelerates current transfer, thereby ensuring that the conversion efficiency is not affected while the area is increased. But Staja said that drones have very strict requirements for battery durability and weight, and the technology will face many problems before it matures.

China’s first dye-sensitized solar cell industrialization project with a total investment of 150 million yuan was settled in Hebei Youdan Development Zone at the end of December 2009, marking a new generation of solar cells independently developed by China – the industry of dye-sensitized solar cells The process of transformation has reached a new level. According to reports, the production technology of dye-sensitized solar cells has completely independent intellectual property rights, and the technical level is synchronized with the world, breaking the foreign technology monopoly.

South Korea started mass production of commercial window solar panels in 2010, a national laboratory in South Korea announced. The move contributes to massive reductions in electricity use in buildings, vehicles and electronic equipment. South Korea’s Dongjin Corporation purchased the manufacturing technology patent for dye-sensitized solar cells developed by the institution. This technology can be applied to the manufacture of colored windows, etc. According to the Korea Institute of Science and Technology, “this new type of solar cell works similar to the photosynthesis of plants and can convert more light into energy.” Although dye-sensitized solar cells are not as energy efficient, they are cheaper. . After 10 years of research and development, the energy efficiency of this solar panel has reached 11%,

But its cost is only one-fifth of the silicon solar panels that are widely used today. The average energy efficiency of traditional solar panels is 12% to 15%, and this new type of solar cell is expected to work for more than 20 years, which is similar to the life cycle of traditional silicon solar cells. Experts predict that the demand for various solar cells in the global market will reach 120 trillion won (about 118.9 billion US dollars) by 2015, of which more than 30% of the solar cells will be dye-sensitized solar cells and other related products.

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