Gold Nanorod Plasmonic Layers for Selective Near-IR Blocking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional technologies for controlling light transmission and absorption in devices, such as electrochromic windows and displays, face limitations in efficiently managing near-IR radiation while maintaining visible light transmission, often resulting in energy wastage and high costs due to the use of thin metal and dielectric layers.
Innovation Solution
The development of nanoengineered devices incorporating noble metal nanoparticles, specifically gold nanorods, which are deposited in a multilayer structure with dielectric layers to adjust light absorption and transmission, allowing for selective blocking of near-IR radiation without obstructing visible light, using techniques like seed-assisted and electrochemical methods for fabrication.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If thin metal and dielectric layers are used to control light transmission, then light transmission control is achieved, but energy wastage and cost increase
Solution Approach 1:
The patent changes the physical parameters by using noble metal nanoparticles with specific sizes (10-100 nm) and shapes (spheres, rods, prisms, cubes) that exhibit surface plasmon resonance at different wavelengths. By adjusting nanoparticle size, shape, and composition, the optical properties are tuned to achieve selective near-IR blocking while maintaining visible light transmission, eliminating the need for thick metal and dielectric layers that cause energy wastage.
Solution Approach 2:
The patent employs composite structures combining noble metal nanoparticles with dielectric materials (such as silicon dioxide, titanium dioxide, or zinc oxide) deposited in multilayer configurations. These composite materials leverage the plasmonic properties of metal nanoparticles for selective light absorption and the dielectric layers for structural stability and additional optical control, achieving superior energy management compared to conventional single-material approaches.
2Object-affected harmful factors
If conventional electrochromic windows are used to block near-IR radiation, then radiation blocking is achieved, but visible light transmission is obstructed
Solution Approach 1:
The patent applies local quality by designing nanoparticles with specific shapes and sizes that target particular wavelength ranges. For example, gold nanorods with aspect ratios of 2-4 resonate in the near-IR region, while smaller gold nanospheres resonate in the visible range. This allows the window to selectively block near-IR radiation while maintaining high visible light transmission, as each nanoparticle type is optimized for its specific wavelength target.
Solution Approach 2:
By changing the optical parameters through nanoparticle selection, the patent achieves wavelength-selective absorption. The surface plasmon resonance frequency is tuned by adjusting nanoparticle size and shape parameters, enabling the material to absorb harmful near-IR radiation at specific resonant frequencies while remaining transparent to visible light wavelengths that do not match the nanoparticle resonance conditions.
3Illumination intensity
If noble metal nanoparticles are used to control light absorption, then selective wavelength control is improved, but manufacturing complexity increases
Solution Approach 1:
The patent segments the optical control function into discrete nanoparticle components, each responsible for specific wavelength absorption. Different nanoparticle types (gold spheres for visible, gold nanorods for near-IR, silver nanoparticles for UV) are independently synthesized and then deposited in controlled layers. This segmentation allows for modular manufacturing where each layer can be optimized and controlled separately, reducing overall manufacturing complexity despite the advanced functionality.
Solution Approach 2:
The patent replaces complex mechanical or electronic control systems with passive optical properties of nanoparticles. Instead of using active electrochromic materials that require electrical control mechanisms, the invention uses the inherent surface plasmon resonance properties of metal nanoparticles to achieve automatic wavelength-selective absorption based on the incident light wavelength, significantly simplifying the manufacturing and operation of the device.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enables efficient control of light absorption and transmission across various wavelengths, reducing energy wastage and costs by using gold nanorods in close proximity to enhance surface plasmon interactions, achieving adjustable optical density and sharp cut-off wavelengths, thus optimizing energy management in residential and commercial settings.
Implementation Method 1
Noble metal nanoparticles such as gold nanospheres and nanorods have been of great research interest and have become very promising nanomaterials in applications such as photothermal cancer therapeutics, biological imaging in the near-infrared region, surface-enhanced Raman scattering sites
Data Source
AI summary
This invention provides application of noble metal nanoparticles for devices with controlled light transmission, absorption and detection. Particularly described is the use of noble metal nanoparticles in photoconductive detectors, optical filters, optical switches, pixel arrays, and electrochromic windows for controlling the transmission and absorption of incident and transmitted light. In addition, the use of noble metal nanoparticles in an electrochromic display is described in which color of the transmitted light from a nanoparticle-based pixel is adjusted and controlled.