Summary:
UCLA researchers in the Department of Materials Science and Engineering have developed a novel photo-responsive polymer that can in real-time detect, track, modulate, and harvest incident optical signals and a broad range of energetic emissions at high accuracy and fast response rate.
Background:
The capability to efficiently and simultaneously detect, track and harvest or modulate signals (e.g. optical, electromagnetic, and acoustic) are vital for a broad range of optics, photonics, optoelectronics and also national-security technologies. Current state of the art relies on tuning the physical properties of the surface materials or employing electronics and computer programmed systems, which lack the ability to adaptively interact and engage with the signals. Waveguides can direct the signals but are normally cm-scale, rigid and heavy, as they are made of metallic materials. Current dominant technology that can both detect and follow the signal uses MEMS-based or pre-programmed electronics to lift and tilt the entire heavy photo-detecting panel or fold the electromagnetic-receiving antenna towards the incident signals, combining the discrete processes of sensing and actuation at high fabrication and operation costs. There is a need for an efficient, affordable and operationally simple method to detect and harvest electromagnetic signals for a wide array of applications.
Innovation:
UCLA researchers have created a novel soft, light-weighted and micron-scale artificial phototropic material. This technology is inspired by living plants' ability to orient their leaves towards sunlight, known as phototropism, which improves their photosynthesis capabilities. It utilizes a photo-responsive polymer which detects, tracks, modulates, and harvests incident optical signals in real time with high accuracy. By incorporating a variety of components and absorbers, the system can induce a wide range of response behaviors and can be utilized for a versatile set of applications. For example, the efficiency of pure water production from wastewater or seawater has outperformed the reported solar vapor generation-based water distillation technologies to date. This material system has significantly enhanced the water evaporation efficiency in desalinization and distillated water generation applications. This solution presents a next-generation, high-efficiency water purification technology. In addition, remarkably high efficiency in solar energy harvesting at various incident angles have been achieved. This is due to the material's effective ability of minimizing the incident angle-induced energy loss as the sun moves across the sky during the day. The applications of this innovation are vast, ranging from water sanitation and clean energy generation.
Demonstration Videos:
Video: SunBOT Tracking Light of Variable Incident Angles
Video: SunBOT Omnidirectional Continuous Tracking
Patent:
Materials for autonomous tracking, guiding, modulating, and harvesting of energetic emissions (US11572470B2)
Applications:
- Maximizing photon harvesting in low light condition for solar panel or fuel cells
- Light control in smart window
- Detectors capable of working at low light conditions
- Absorbers with selected response frequency ranges
- Soft variable-angle micro-waveguides and/or modulators
- Angular-definitive, self-adaptive photonic absorber/selective filter
- Self-adaptive, wavelength-independent, and polarization-independent optical diode
- Detectors for various signals if different components incorporated (e.g. acoustic/magnetic-electro-mechanically responsive)
Advantages:
- Fully autonomous and high energy efficiency
- Integratable, easy and low-cost fabrication
- Fast response (at the time scale of 0.5-60 seconds)
- High-accuracy, real-time tracking, harvesting, and directing of optical or other signals
- μm-mm level, soft, light weighted
Featured By:
1. Nature Nanotechnology: News and Views: Actuating Smart
2. ScienceNews: The first artificial material that follows sunlight may upgrade solar panels
3. NewScientist: Tiny artificial sunflowers could be used to harvest solar energy
4. Tweeter: Nature Research
5. Daily Bruin: Researchers create solar energy system inspired by flowers’ light-finding ability