Plasmon-Induced Hot-Electron and Energy Transfer in Nano-Photoanodes for Efficient Photoelectrochemical Water Oxidation
Physical Sciences : Materials and Compounds
Available for licensing
- Yuebing Zheng, Ph.D. , Mech Engineering
- Jiayong Gan , University of Texas at Austin
Photoelectrochemical (PEC) cells are a promising energy conversion technology. The cells split water into hydrogen and oxygen, which are environment-friendly and are promising for the clean energy provision. PEC cells have the capability of integrating energy capture, conversion, and storage in a single integrated system, and can be widely used to produce renewable energies in a large scale. However, the full implementation of PEC cells requires the development of new electrode materials with higher solar energy conversion efficiency than current technology.
Nanostructures of semiconductors as photoanodes for PEC cells have been intensely explored to improve charge separation yield and energy conversion efficiency. Recently, plasmonic metal nanostructures, which can localize optical energy and control the charge carrier generation with surface plasmon resonances (SPR), are emerging to further enhance energy conversion efficiency in PEC cells. However, the design of composite photoanodes has relied on a trial-and-error approach, leading to only moderate performance enhancement.
Researchers at The University of Texas at Austin have developed a nanoporous Bismuth Vanadate (BiVO4) substrate with plasmonic Au nanoparticles as the photoanode material for PEC cells. The specific materials developed for this purpose are unique in their form as nanoporous arrays synthesized in an electrochemical deposition process. Furthermore, the plasmonic effects of Au nanoparticles in the photoanodes have been decoupled. The anode system achieves the maximum power point for solar water oxidation with long-term stability.
This invention paves the way towards the first-principle design of plasmon-enhanced nanostructured photoanodes based on deep mechanistic studies that decouple the plasmonic enhancement mechanisms in PEC cells. These robust and simple electrochemical methods enable the low-cost and large-scale fabrication of the Au-BiVO4 and other related photoanodes. With high performance through the optimization of each of the enhancement mechanisms, the Au-BiVO4 nanostructures represent the next-generation photoanode materials in a practical water splitting system.
- High-efficiency solar water splitting
- Simple fabrication and high stability of devices
- Potential for low-cost and large-scale implementation
- Facile and robust fabrication of photoanodes with high performance
- Plasmonic enhancement mechanisms are decoupled and optimized individually
- Large bandwidth of solar irradiation is effectively utilized
- Scalable to industrial process conditions
- Performance comparable to state-of-the-art techniques
Industrial gas providers, solar cell fabricators, and clean energy companies could be interested in this technology.
The global fuel cell market is expected to grow from an estimated $2.61 billion in 2014 to $5.20 billion by 2019, with a CAGR of 14.7% from 2014 to 2019.