Scientists use solar energy to break water into hydrogen and oxygen
 |
Scientists have made many major breakthroughs in finding cheap, clean energy: they use crude algae to make crude oil in a matter of minutes, use plastic shopping bags to make diesel, and discover edible oil microbes. Power generation is no longer the only way to convert daylight into usable energy. The sun can also promote chemical reactions and produce chemical fuels such as hydrogen.
The difficulty in producing solar fuels is that both the semiconductors used to obtain solar energy and the fuel-producing catalysts are costly. The most effective materials are too expensive, leading to the production of fuel that cannot compete with gasoline on price.
However, some researchers have now found a way to use solar energy to split water into hydrogen and oxygen with a conversion rate of up to 1.7%, which is the highest conversion rate in oxygen-based photoelectrode systems.
Kyoung-Shin Choi, professor of chemistry at the University of Wisconsin-Madison, used yttrium vanadate to create a solar cell that uses the principle of electrodeposition. The surface area per gram of yttrium vanadate can reach 32 square meters.
To speed up the energy production of bismuth vanadate, you need to use catalysts. Although many research teams are dedicated to the development of electrodeposited semiconductors, many teams are developing water-decomposing catalysts, but according to Choi, not many people are concerned about the combination of semiconductors and catalysts.
Moreover, researchers have said that plastic shopping bags can be converted into diesel, natural gas and other useful petroleum products.
The energy generated by this conversion far exceeds the energy required for the conversion process, which can produce diesel and other transportation fuels, which can be mixed with existing ultra-low sulphur diesel and biodiesel. Other products, such as natural gas, petroleum spirits, gasoline, paraffin and lubricating oil, can also be produced in shopping bags. This production process is called pyrolysis and the plastic bags are heated in an oxygen-free room. According to Brajendra Kumar Sharma, a senior researcher at the Illinois Center for Sustainable Technology who led the study, this production method has other uses.
At the same time, engineers at the U.S. Department of Energy’s Pacific Northwest National Laboratory (PNNL) have developed a continuous chemical process that dumps seaweed into place and produces crude oil in a matter of minutes.
Genifuel, a biofuels company based in Utah, has a patent for this technology and is now working with an industry partner to build a lab to take advantage of this technology.
In this process developed by PNNL, the front end of the chemical reactor in the algae mucus is poured in. After the system is started up, crude oil can be produced in less than an hour. At the same time, water and a phosphorus-containing by-product can also be produced, which can be recycled to grow seaweed.
After additional conventional refining, crude oil produced from seaweed can be converted into aviation fuel, gasoline, or diesel. Wastewater from this process can also be further processed to produce combustible gases, potassium, nitrogen, and other substances that can be mixed with purified water to grow seaweed.
Duke's research team found a better way to make artificial cartilage in joints. Professor Farshid Guilak, an orthopedic surgeon, and Xuanhe Zhao, an assistant professor of medical engineering and materials science, combined the two innovative technologies to find a way to create artificial tissue that combines the strength and softness of natural cartilage. Cartilage is located in the joints of the body and, over time, can be damaged due to injury or excessive use, causing pain and no longer being flexible. Natural cartilage is both tough and weight-bearing. It is both smooth and soft. It is very difficult to replace it with artificial materials.
Salinary bacteria is a very adaptable bacteria. They can tolerate the heat, salt, oxygen, darkness, and high-pressure environment that would kill most other creatures. This allows them to survive deep in the sandstone, which is conducive to hydrocarbon extraction and carbon sequestration.
At the same time, algae has been considered as a potential source of biofuels, and several companies are studying the use of seaweed to make fuel, but the cost is quite high. PNNL's technology effectively exploits the potential of algae and uses several methods to reduce the cost of producing fuel from seaweed.
PNNL scientists and engineers have integrated several chemical steps into one continuous process that simplifies the use of seaweed to produce fuel. The most important cost reduction measure is that the production process uses wet seaweed. Most existing processes require the drying of algae, which consumes energy and increases costs. This new process uses seaweed mixture, of which 80% to 90% are water.
Although there are still some teams that are trying to make biofuels in a similar way, most of them are finished one batch at a time. The PNNL's system is continuously operating. In the equipment used in the laboratory, 1.5 liters of seaweed mixture can be processed per hour. Although this does not seem to be much, it is already very close to the requirements of large-scale commercial production.
The PNNL system also eliminates the steps that are now common in the seaweed process, which uses solvents such as ethane to extract energy-rich oil from the algal residue. Instead, the PNNL team uses all the seaweeds, places them under high temperature and pressure, and converts most of their biomass into liquid and gaseous fuels.
The products of this system include:
· Crude oil can be converted into aviation fuel, gasoline or diesel. According to the team's experience, about 50% of the carbon in seaweed can be converted to energy in crude oil - sometimes up to 70%.
· Purified water can be recycled to grow more seaweed.
· Fuel gas, which can be burned to generate electricity or purified to produce natural gas for automobiles.
· Nitrogen, phosphorus, potassium, and other nutrients - are also key nutrients required for seagrass cultivation.
An analysis of microbial metabolism found that these bacteria can use iron and nitrogen in their environment and recycle rare nutrients to meet their metabolic needs.
Perhaps most importantly, the team found that these microbes living deep in the rocks can metabolize the aromatic compounds common in oil.
Electronic Locks,Cylinder Locks,Stainless Steel Locks,Stainless Steel Door Lock
Ningbo Hengchieh Locking Technology Co., Ltd. , https://www.hengchieh.com