Graphene solar cells can achieve 60% of the photoelectric conversion rate?

More than 150 years ago, since the advent of lead-acid batteries, the bold idea of ​​innovative battery technologies has always existed. Recently, the University of Manchester in the United Kingdom published a new study in the journal Nature, graphene film can be used to extract atmospheric hydrogen, its application to the field of fuel cells will be possible for the air power generation technology. The scientific community said this is the most revolutionary advance in battery technology. "This study is easy to use and has great potential for growth," said Professor ShengHu, a postdoctoral researcher on the project. "Nowadays, graphene can be produced into a square meter sheet and its application in commercial fuel cells It is not too late. " In 2004, at the University of Manchester's laboratory, research teams led by Andrew Geim and Kostya Novoselov successfully isolated graphene from graphite and proved that graphene can stand alone. As a result, they both won the 2010 Nobel Prize in Physics. Since then, graphene has always been regarded as a reversal of the world of science and technology. The core of this research lies in the excellent physical properties of graphene, which has the same atomic structure as graphite in ordinary pencils. As the first two-dimensional crystal discovered by the scientific community, graphene is the thinnest and hardest substance. It has only one carbon atom and is 100 million times thinner than human hair. It is harder than diamond, breaking strength is 200 times that of steel. At the same time its flexibility and ductility is also very good color, the stretch can reach 20% of its size, graphene is almost transparent, with superior superconductivity of copper. The physical properties of graphene are pioneering in all aspects and are bound to set off a technological revolution that encompasses everything from smartphones and wearable technologies to green technology and healthcare. A nitrogen dioxide molecule is separated on the outside of a single layer of graphene. High barrier properties of graphene have been well established Known for its high barrier properties, graphene films have long been considered as capable of isolating any molecule or atom. Researchers at the University of Manchester have found that graphene "opens the net" to protons and that protons can easily pass through this ultra-thin crystal. In the case of a continuously increasing temperature and the use of a platinum-based catalyst, the effect is better. This characteristic graphene may become a new ideal material for proton conducting membranes in fuel cells. At present, the most common fuel cell uses oxygen and hydrogen as fuel, and converts the input chemical energy directly into electricity. Proton conductive membranes are the core technology of modern fuel cells. However, the proton conductive membranes currently used in fuel cells are relatively inefficient and prone to fuel infiltration, leading to contamination. "When you understand the working principle of a graphene membrane, it's really easy to set up, as long as it releases a small current to collect pure hydrogen in a hydrogen-containing environment and then the collected hydrogen burns in the fuel cell to generate electricity." Professor ShengHu said . The molecular structure of a graphene crystal that is collecting hydrogen gas, each (blue) carbon atom is attached to a (red) hydrogen atom. The graphene proton-conducting membrane can only pass through protons and thus efficiently collects in the atmosphere Hydrogen, and the purity is very high, significantly improve power generation efficiency and durability. Today's fuel cells use hydrogen as fuel for their fuels, and graphene-based fuel cells require only hydrogen in the air as raw materials to build a mobile, zero-pollution air-conditioner that is not far from us. At present, scientists use only small graphene films to do research, so the successful inflow of hydrogen is still very small. This study is still in its infancy, which has given the scientific community insight into the current landscape of graphene films and further work is required to build a practical hydrogen collection machine. In addition to making air-power technology a reality, there are other new uses for graphene. The excellent elasticity and ductility of graphene make it the ideal candidate for solar cells. Recent research at a photonic science institute in Spain shows that graphene can convert electricity more efficiently than silicon. Silicon absorbs only one photon each can produce a current electron, and graphene can produce multiple electrons. Although the current application of graphene in the solar cell field is still in the theoretical stage, its potential is staggering. Graphene solar cells can achieve 60% of the photoelectric conversion rate, is currently twice the maximum efficiency of crystalline silicon solar cells. Graphene thin and hard properties can provide better production materials for car, aircraft manufacturers, transport made of graphene will greatly reduce fuel consumption; studies have shown that graphene can be delivered to specific locations in the body, in the treatment Brain diseases are promising; graphene membranes can also be used to filter seawater, extract salt and other impurities, and purify drinking water.