Nano-Optoelectronic Materials and Devices

Molecular Beam Epitaxial Growth of III-Nitride Nanostructures

We study the epitaxial growth and characterization of high quality III-nitride nanowires on both Si, sapphire and other substrates for optoelectronic devices including light-emitting diodes (LEDs), lasers diodes, solar cells, solar-fuel cells, and photodetectors.

   InGaN/GaN nanowires on Si      

InGaN/AlGaN multi-quantum well core-shell nanowires


Full-color InGaN/GaN LEDs on Transparent/Metal Substrates for Flexible Electronics

We develop the integrations of LEDs in which LEDs can be fabricated on a flexible platforms for conformal indoor lighting, flexible displays, and integrated water purification systems.

Nanowire LEDs on Cu substrate


III-V Nanowire Solar Cells

We are developing single- and multi-junction InGaN nanowire solar cells on a Si platform. Nanowires will be grown directly on Si substrates under nitrogen rich conditions by MBE. By varying the indium and gallium compositions in the nanowire, the nanowire bandgap, or the absorption spectra, can be optimized to achieve solar cells with improved efficiency.

Single (left) and multi-junction (right) solar cells using InGaN/GaN nanowire heterostructures


Photoelctrochemical (PEC) Water Splitting and Hydrogen Generation Using III-Nitride Nanowire Arrays

We study the design, epitaxial growth, and characterization of multi-band InGaN nanowire heterostructures and the solar power driven photocatalytic reaction. PEC water splitting is recognized as one of the key sustainable technologies to provide environmentally friendly solution to the worldwide energy crisis since it directly converts solar energy into hydrogen: a carbon-free, affordable and sustainable source of energy.

III-nitride nanowires for solar-to-hydrogen experiment