Scientists discover a process that could enhance our ability to harvest energy from the Sun for electricity and fuels.
A process to enhance the performance of solar technologies such as solar cells and photocatalysts, and potentially make their production cheaper, has been discovered by scientists.
Solar cells take energy from the Sun and convert it into electricity. But energy from the Sun can also be harnessed to create other fuels such as hydrogen, which could be used for example in cars. These ‘solar fuels’ are produced by mimicking photosynthesis, the process used by plants to create energy from sunlight.
Solar fuels could help tackle climate change, as they can be created without producing carbon dioxide, a greenhouse gas. They could also directly replace fossil fuels in many applications.
However, photosynthesis is complicated process, and there are several challenges to its replication. One of these challenges is that catalysts – materials that help the reaction proceed – are often expensive and inefficient, preventing the process from being easily scaled up.
In a new study, published in the journal Advanced Materials last week, researchers from Imperial College London and Queen Mary University of London (QMUL) demonstrate that a unique property of the material barium titanate could lead to more efficient solar cells and catalyst systems.
The toxic and expensive phosphors used widely in fluorescent lighting could be eliminated thanks to a new study conducted by a materials scientist at Queen Mary University of London (QMUL).
Writing in the journal Nature Materials, the international group of scientists modified a mineral called zeolite, more commonly found in washing powder, to incorporate tiny clusters of silver atoms.
At this very small scale (less than 10 atoms), the silver clusters act very differently and can even emit light.
Lead author Dr Oliver Fenwick from QMUL’s School of Engineering and Materials Science, said: “We’ve shown that silver atoms can be assembled in the porous framework of minerals known as zeolites with a level of control not reported previously. This has allowed us to tailor very precisely the properties of the silver clusters to meet our needs – in this case an efficient phosphor.
“The high efficiency of the materials along with cheap, scalable synthesis makes them very attractive as next generation emitters for fluorescent lamps, LEDs and for biological imaging, for example for highlighting tumours or cell division.”
Queen Mary University of London (officially abbreviated QMUL, informally known as QM) is a public research university located in London, United Kingdom, and a constituent college of the federal University of London.
With roots dating back to the founding of the London Hospital Medical College in 1785, Queen Mary College was admitted to the University of London in 1915, named after Mary of Teck, Queen of the United Kingdom. In 1989 Queen Mary College merged with Westfield College to form Queen Mary and Westfield College. In 1995, Queen Mary and Westfield College merged with two distinguished medical colleges, St Bartholomew’s Hospital Medical College, established in 1843, and the London Hospital Medical College, England’s first medical school, founded in 1785. In 2013, the legal name of Queen Mary and Westfield College, University of London was officially changed to Queen Mary University of London to reflect common usage.
Queen Mary’s main campus is located in the Mile End area of the East End of London, with other campuses in Holborn, Smithfield and Whitechapel. It has around 17,000 full-time students and 4,000 staff and an annual turnover of £350 million, of which around £100 million is from research grants and contracts. Queen Mary is organised into three faculties – the Faculty of Humanities and Social Sciences, the Faculty of Science and Engineering and Barts and The London School of Medicine and Dentistry – within which there are 21 academic departments and institutes. It is one of the largest colleges of the University of London.
Queen Mary is a member of the Russell Group of leading British research universities, the Association of Commonwealth Universities and Universities UK. Queen Mary is a major centre for medical teaching and research and is part of UCL Partners, the world’s largest academic health science centre. It has a strategic partnership with the University of Warwick, including research collaboration and joint teaching of English, history and computer science undergraduates. Queen Mary also collaborates with Royal Holloway, University of London to run programmes at the University of London Institute in Paris. There are five Nobel Laureates amongst Queen Mary’s alumni and current and former staff.
The Latest Updated Research News:
Queen Mary University of London research articles from Innovation Toronto
- The toxic and expensive phosphors used widely in fluorescent lighting could be eliminated – June 9, 2016
- ‘Pee power’ turns urine into sustainable power source for electronic devices – April 20, 2016
- Modified flu virus can ‘resensitize’ resistant pancreatic cancer cells to chemotherapy – April 15, 2016
- Smaller, Cheaper Microbial Fuel Cells Turn Urine into Electricity – March 17, 2016
- Just When You Thought the Universe Was Safe: General Relativity Could Break Down – February 22, 2016
- Self-assembling material that grows and changes shape could lead to artificial arteries – September 30, 2015
- Understanding of complex networks could help unify gravity and quantum mechanics – September 11, 2015
- Most internet anonymity software leaks users’ details – July 1, 2015
- Cheap solar cells made from shrimp shells – March 2, 2015
- New ‘microcapsules’ have potential to repair damage caused by osteoarthritis – January 26, 2015
- Revolutionary device found to lower blood pressure – January 24, 2015
- Study reveals text messages prevent 1 in 6 patients from failing to take medicine – December 8, 2014
- Magic tricks created using artificial intelligence for the first time – November 17, 2014
- Mobile phones come alive with the sound of music – August 19, 2014
- Criminal profiling technique targets killer diseases – June 24, 2014
- Big beats bolster solar cell efficiency
- Accidental nanoparticle discovery could hail revolution in manufacturing
- Synthetic polymer could stop the spread of HIV
A new design could help produce sustainable energy in developing countries
A new kind of fuel cell that can turn urine into electricity could revolutionize the way we produce bioenergy, particularly in developing countries. The research, published in Electrochimica Acta, describes a new design of microbial fuel cell that’s smaller, cheaper and more powerful than traditional ones.
The world’s supply of fossil fuels is being depleted, and there is increasing pressure to develop new renewable sources of energy. Bioenergy is one such source, and microbial fuel cells can produce it.
In their study, researchers from University of Bath, Queen Mary University of London and the Bristol Robotics Laboratory describe a new design of microbial fuel cell that overcomes two limitations of standard microbial fuel cells: their cost and low power production.
“Microbial fuel cells have real potential to produce renewable bioenergy out of waste matter like urine,” said Dr. Mirella Di Lorenzo, corresponding author of the study from the University of Bath. “The world produces huge volumes of urine and if we can harness the potential power of that waste using microbial fuel cells, we could revolutionize the way we make electricity.”
Microbial fuel cells are devices that use the natural processes of certain bacteria to turn organic matter into electricity. There are other ways of producing bioenergy, including anaerobic digestion, fermentation and gasification. But microbial fuel cells have the advantage of working at room temperature and pressure. They’re efficient, relatively cheap to run and produce less waste than the other methods.
There are, however, some limitations. Microbial fuel cells can be quite expensive to manufacture. The electrodes are usually made of cost-effective materials, but the cathode often contains platinum to speed up the reactions that create the electricity. Also, microbial fuel cells tend to produce less power than the other methods of bioenergy production.
The new miniature microbial fuel cell uses no expensive materials for the cathode; instead it’s made of carbon cloth and titanium wire. To speed up the reaction and create more power, it uses a catalyst that’s made of glucose and ovalbumin, a protein found in egg white. These are typical constituents of food waste.
“We aim to test and prove the use of carbon catalysts derived from various food wastes as a renewable and low-cost alternative to platinum at the cathode,” said corresponding author Dr. Mirella Di Lorenzo from the University of Bath.
They then tweaked the design to see what would produce more power. Doubling the length of the electrodes, from 4mm to 8mm, increased the power output tenfold. By stacking up three of the miniature microbial fuel cells, the researchers were able to increase the power tenfold compared to the output of individual cells.
“Microbial fuel cells could be a great source of energy in developing countries, particularly in impoverished and rural areas,” said Jon Chouler, lead author of the study from the University of Bath. “Our new design is cheaper and more powerful than traditional models. Devices like this that can produce electricity from urine could make a real difference by producing sustainable energy from waste.”
“We have shown that the cell design has an incidence on performance and we want to further investigate the relevance of electrode surface area to volume ratio on performance. Our aim is to be able to effectively miniaturize the MFC and scale-up power production by generating compact batteries of multiple miniature units,” added Dr. Di Lorenzo.
Researchers at the University of Bath have developed an innovative miniature fuel cell that can generate electricity from urine, creating an affordable, renewable and carbon-neutral way of generating power.
In the near future this device could provide a means of generating much needed electricity to remote areas at very little cost, each device costs just £1-£2. With growing global pressures to reduce reliance on fossil fuels and the associated greenhouse gas emissions, microbial fuel cells could be an exciting alternative.
A microbial fuel cell is a device that uses natural biological processes of ‘electric’ bacteria to turn organic matter, such as urine, into electricity. These fuel cells are efficient and relatively cheap to run, and produce nearly zero waste compared to other methods of electricity generation.
In practice, urine will pass through the microbial fuel cell for the reaction to happen. From here, electricity is generated by the bacteria which can then be stored or used to directly power electrical devices.
The research team from the University’s Department of Chemical Engineering, Department of Chemistry and the Centre for Sustainable Chemical Technologies (CSCT), have worked with Queen Mary University of London and the Bristol Bioenergy Centre, to devise this new kind of microbial fuel cell that is smaller, more powerful and cheaper than other similar devices.
This novel fuel cell developed by the researchers, measures one inch squared in size and uses a carbon catalyst at the cathode which is derived from glucose and ovalbumin, a protein found in egg white. This biomass-derived catalyst is a renewable and much cheaper alternative to platinum, commonly used in other microbial fuel cells.
The researchers worked on the cell’s design to maximize the power that could be generated. By increasing the cell’s electrodes from 4mm to 8mm, the power output was increased tenfold. Furthermore, by stacking multiple units together, the power was proportionally increased.
Currently, a single microbial fuel cell can generate 2 Watts per cubic metre, enough to power a device such as a mobile phone. Whilst this value is not comparable with other alternative technologies such as hydrogen or solar fuel cells and other methods of bioenergy digesters, the significant advantage of this technology is its extremely cheap production cost and its use of waste as a fuel, a fuel that will never run out and does not produce harmful gasses.
The research team is now looking at ways of improving the power output of the microbial fuel cell and is confident that by optimising the design of the cell, they will be able to increase the cell’s performance.
Lecturer in the University of Bath’s Department of Chemical Engineering and corresponding author, Dr Mirella Di Lorenzo, said: “If we can harness the potential power of this human waste, we could revolutionise how electricity is generated.
“Microbial fuel cells can play an important role in addressing the triple challenge of finding solutions that support secure, affordable, and environmentally sensitive energy, known as the ‘energy trilemma’.
“There is no single solution to this ‘energy trilemma’ apart from taking full advantage of available indigenous resources, which include urine.”
Lead author and CSCT PhD student, Jon Chouler said: “Microbial fuel cells could be a great source of energy in developing countries, particularly in impoverished and rural areas.
“To have created technology that can potentially transform the lives of poor people who don’t have access to, or cannot afford electricity, is an exciting prospect. I hope this will enable those in need to enjoy a better quality of life as a result of our research.”
Researchers have successfully simulated how a ring-shaped black hole could cause general relativity to break down: assuming the universe contains at least five dimensions, that is.
As long as singularities stay hidden behind an event horizon, they do not cause trouble and general relativity holds
Researchers have shown how a bizarrely shaped black hole could cause Einstein’s general theory of relativity, a foundation of modern physics, to break down. However, such an object could only exist in a universe with five or more dimensions.
The researchers, from the University of Cambridge and Queen Mary University of London, have successfully simulated a black hole shaped like a very thin ring, which gives rise to a series of ‘bulges’ connected by strings that become thinner over time. These strings eventually become so thin that they pinch off into a series of miniature black holes, similar to how a thin stream of water from a tap breaks up into droplets.
Ring-shaped black holes were ‘discovered’ by theoretical physicists in 2002, but this is the first time that their dynamics have been successfully simulated using supercomputers. Should this type of black hole form, it would lead to the appearance of a ‘naked singularity’, which would cause the equations behind general relativity to break down. The results are published in the journal Physical Review Letters.
General relativity underpins our current understanding of gravity: everything from the estimation of the age of the stars in the universe, to the GPS signals we rely on to help us navigate, is based on Einstein’s equations. In part, the theory tells us that matter warps its surrounding spacetime, and what we call gravity is the effect of that warp. In the 100 years since it was published, general relativity has passed every test that has been thrown at it, but one of its limitations is the existence of singularities.
A singularity is a point where gravity is so intense that space, time, and the laws of physics, break down. General relativity predicts that singularities exist at the centre of black holes, and that they are surrounded by an event horizon – the ‘point of no return’, where the gravitational pull becomes so strong that escape is impossible, meaning that they cannot be observed from the outside.
“As long as singularities stay hidden behind an event horizon, they do not cause trouble and general relativity holds – the ‘cosmic censorship conjecture’ says that this is always the case,” said study co-author Markus Kunesch, a PhD student at Cambridge’s Department of Applied Mathematics and Theoretical Physics (DAMTP). “As long as the cosmic censorship conjecture is valid, we can safely predict the future outside of black holes. Because ultimately, what we’re trying to do in physics is to predict the future given knowledge about the state of the universe now.”
But what if a singularity existed outside of an event horizon? If it did, not only would it be visible from the outside, but it would represent an object that has collapsed to an infinite density, a state which causes the laws of physics to break down. Theoretical physicists have hypothesised that such a thing, called a naked singularity, might exist in higher dimensions.
“If naked singularities exist, general relativity breaks down,” said co-author Saran Tunyasuvunakool, also a PhD student from DAMTP. “And if general relativity breaks down, it would throw everything upside down, because it would no longer have any predictive power – it could no longer be considered as a standalone theory to explain the universe.”
We think of the universe as existing in three dimensions, plus the fourth dimension of time, which together are referred to as spacetime. But, in branches of theoretical physics such as string theory, the universe could be made up of as many as 11 dimensions. Additional dimensions could be large and expansive, or they could be curled up, tiny, and hard to detect. Since humans can only directly perceive three dimensions, the existence of extra dimensions can only be inferred through very high energy experiments, such as those conducted at the Large Hadron Collider.
Einstein’s theory itself does not state how many dimensions there are in the universe, so theoretical physicists have been studying general relativity in higher dimensions to see if cosmic censorship still holds. The discovery of ring-shaped black holes in five dimensions led researchers to hypothesise that they could break up and give rise to a naked singularity.
What the Cambridge researchers, along with their co-author Pau Figueras from Queen Mary University of London, have found is that if the ring is thin enough, it can lead to the formation of naked singularities.