On February 7, 2002, Nature 415, 599 (2002) published the work of Gao Yihua: the world's first study of the expansion properties of nanoscale liquid substances, and the use of Ga-filled carbon nanotubes to develop the world's "smallest thermometer." On September 30, 2005, Gao Yihua and his two leaders: Prof. Yoshio Bando (team leader) and Prof. Dmitri Golberg (deputy team leader), won the 16th International Prize for the development of new nanotubes and the invention of nanothermometers. The prestigious Tsukuba Prize for Outstanding Scientists in Japan [Tsukuba Prize] was awarded by Professor Leo Esaki, who won the Nobel Prize in Physics in 1973; at the press conference, Professor Leo Esaki, who won the Nobel Prize in Chemistry in 2000 Professor Hideki Shirakawa and others accompanied the three TsukubaPrize winners to take commemorative photos].
Gao Yihua has also achieved a series of representative results as described below.
Integrating basic physical principles and concepts such as thermal dynamic balance, force balance and electrical balance, a new anomalous large expansion effect was discovered - the Ga microspheres in the SiO2-wrapped microsphere shell and nanotube composite structure Electrohydraulic expansion effect [Appl.Phys.Lett. 99, 083112(2011)].
Through a simple chemical vapor deposition method, an alloyed GaxZn1-xO nanowire array is prepared on a p-type GaN substrate to form a GaxZn1-xO nanowire/p-GaN substrate LED device, achieving a band gap Based on the recombination of interface electron-hole pairs, the electroluminescence wavelength is red-shifted from the ZnO ultraviolet wavelength of 382 nm ~100nm to 480nm in the visible light region, which solves the problem that the existing ZnO doping energy band adjustment wavelength is too narrow (only 50nm) [Laser PhotonicsRev.8, 429–435(2014)]. By regulating the energy band of p-type doping of ZnO nanoarray Sb, a white light LED without ultraviolet emission is obtained, which solves the problem that existing GaN-like white light LEDs must be adjusted with the help of phosphors to emit white light [Adv.Funct.Mater.DOI :10.1002/adfm.201404316].
Conduct research on light-to-electricity conversion of woven energy devices. Based on the importance of using simple methods to improve the electron transmission efficiency and photon capture efficiency to achieve high conversion efficiency of knitted solar cells, a one-step hydrothermal method was used to grow a length of several times on Ti wires with a diameter of 0.5 mm. The trunk-like TiO2 nanowires on the order of ten microns and the dense TiO2 nanobranching on the trunk overcome the shortcomings of cumbersome existing research steps, simply construct long-distance electron transmission channels and increase the large specific surface area for light absorption, and develop a conversion efficiency of up to 6.32 fiber dye-sensitized solar cells [Sci. Rep. 4, 4420 (2014)].
Carry out preliminary research work on solar energy storage - research on high-performance solid-state flexible supercapacitors: Research on solid-state flexible supercapacitors with polypyrrole-manganese dioxide-micron carbon fiber composite structures that can drive micro devices [body Capacitance density 69.3F/cm2, Sci.Rep.3, 2286 (2013)], cotton thread-based three-dimensional multi-level nanostructure supercapacitor for portable energy storage [Adv.Mater.25, 4925 (2013), surface capacitance Density 1.49F/cm2] and high-capacity polypyrrole-manganese dioxide asymmetric supercapacitor with hierarchical nanostructure [Nanoscale6, 2922 (2014), surface capacitance density 1.41F/cm2, energy density 0.63mWh/cm2, power density 0.9 mW/cm2] research. Energy storage units composed of these flexible supercapacitors have successfully driven commercial small LCD screens, LEDs, motors and toy electric vehicles.
These works provide direct microscopic evidence that nanostructured manganese dioxide is susceptible to corrosion in acidic electrolytes and a solution to this problem. By developing asymmetric electrodes, the operating voltage is increased. Cleverly coating with organic conductive materials not only solves the corrosion resistance problem of the active material manganese dioxide, ensuring the full play of its electrochemical performance, but also increases the transmission channels for electrons and ions in the electrochemical process, further improving the performance of the device. capacitive performance. These studies have important reference value for the application of organic-inorganic composite materials in supercapacitors.
So far, Gao Yihua*** has obtained 2 Chinese patents, 2 U.S. patents and 6 Japanese patents, and is applying for 9 Chinese patents. Currently engaged in research on energy conversion, storage and detection of nanomaterials and devices, which is divided into three main directions: 1. LED research and light detection research on nano-oxide arrays; 2. Light-to-electricity conversion and electrical energy storage of woven solar cells Research; 3. Research on electrical-mechanical conversion and thermal detection of metallic liquid-filled nanotubes.