For Earth ,Bulb use graphene?

In the course of several years of LED's entry into the public view, the progress of technology and the improvement of human's demand have played a major role. Even if the home is not damaged by the traditional lighting, but also gradually replaced by white LED. Because the white LED devices have a huge advantage in power consumption and lighting effects. Although the popularity of LED products to such a point, but still facing this huge problem, is the production of LED raw materials, rare earth elements. In order to solve this problem, researchers are studying a new type of LED, which is made up of rare earth elements and is used to rewrite the white LED technology. The current white LED, also known as white light diode, its white light mainly by the single crystal, polycrystalline two ways to achieve. Polycrystalline mean by LED package of different colors together, through the complementary color display white light. The single way is simple, with a single blue LED and yellow phosphor on the surface of the yellow and blue light LED hybrid phosphor for white light, visual effect. The above two kinds of technology, can not avoid the use of rare earth elements. Recently, researchers at the National Tsinghua University in the "Nano ACS" published an article, which pointed out that the use of rare earth elements in the study of the use of LED products can be made of white light. This LED based on alkali metal strontium, built a metal organic framework (MOF), in combination with the MOF up and down the graphene and other materials, which can directly emit white light LED.MOF is a very promising material, which is formed by the coordination of metal ions and organic materials. In the past 20 years, widely used in chemical separators, drug delivery, gas storage, catalysis and other fields. But it is very difficult to see this material in the field of optoelectronics, because MOF is generally porous, poor conductivity. In the early stage of the study, the MOF of white light can be emitted by different kinds of rare earth elements. In order to solve the above problems, we should switch to better conductive elements, but at the same time, this element can also be used to stimulate the emission of the sub bands of light. With the change of organic ligands, the use of alkaline earth metal strontium preparation of MOF materials.On the MOF surface, the graphene is added to the transparent electrode to improve the carrier mobility, and it will not affect the optical properties. Due to the excellent thermal conductivity of graphene, the thermal conductivity of the new white light emitting diode is better. On the periphery of the MOF material, the researchers also combined the graphene, silicon dioxide, Zinc Oxide. So that it can emit light in the electric drive. The use of MOF materials to manufacture light-emitting devices, gave people a new way of thinking.The test results show that as the light emitting device, display range is very close to the natural light (green point map), as a semiconductor device, its stability is better, during the two months of testing, there is almost no performance degradation. In the performance, the more important the material environmental significance, due to the new LED without the use of a large number of rare elements, to reduce the amount of rare earth elements, rare earth elements and less now, reduce the use of rare earth elements are very important. At the same time, it can reduce the environmental pollution caused by rare earth elements. New material emitted by the light and natural light is very close, there will not be a strong blue light appears. The luminous efficiency can be greatly improved due to the light of other colors are not covered. Reduce the power consumption, greenhouse gas emissions will also be reduced. From the LCD panel more common bulbs to electronic equipment in the equipment to start using LED as light source, no matter from the protection of resources, or from the protection of the environment, the emergence of new white LED technology are excellent.