Plasmonic Metal Nitride Ohmic Junctions for Hot Carrier Collection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing plasmonic nanostructures using noble metals face inefficiencies due to the formation of Schottky barriers with titanium oxide photocatalysts, hindering the transfer of photo-excited hot carriers and reducing system efficiency in plasmon-assisted catalysis.
Innovation Solution
The use of plasmonic metal nitride and transparent conducting oxide core materials forming ohmic junctions with semiconductor elements, such as titanium oxide, to enhance the collection of photo-excited carriers, overcoming the barrier issue and improving efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If noble metals are used to form plasmonic nanostructures, then plasmonic resonance and field enhancement are achieved, but Schottky barriers form with titanium oxide photocatalysts, reducing carrier transfer efficiency
Solution Approach 1:
The patent changes the material parameter from noble metals to transition metal nitrides, which fundamentally alters the electronic structure and eliminates the Schottky barrier formation while preserving plasmonic resonance capabilities in the visible and near-infrared regions
Solution Approach 2:
The patent creates a composite system where transition metal nitride plasmonic nanostructures are integrated with titanium oxide photocatalysts, forming an ohmic junction that enables efficient carrier transfer while maintaining plasmonic field enhancement
2Productivity
If noble metals are used for plasmonic catalysis, then catalytic activity enhancement is achieved, but system efficiency is reduced due to Schottky barrier formation
Solution Approach 1:
The patent changes the material composition from noble metals to transition metal nitrides, which modifies the electronic properties to enable ohmic contact with photocatalysts, thereby reducing energy loss at the interface while maintaining catalytic activity enhancement
Solution Approach 2:
The transition metal nitride acts as an intermediary material that bridges the plasmonic excitation and the photocatalytic reaction, facilitating efficient hot carrier transfer through ohmic junctions while maintaining catalytic functionality
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 collection and utilization of hot carriers, enhancing catalytic activity and system efficiency in applications like solar harvesting and catalytic processes, while maintaining durability at high temperatures.
Implementation Method 1
Plasmonic nanostructures exhibit resonances when illuminated with electromagnetic radiation in the visible and infrared regions of the spectrum. Due to resonant oscillations of electrons, the enhanced optical cross-sections of the subwavelength nanostructures enable localization of the incident electromagnetic energy
Implementation Method 2
Surface plasmons excited by the incoming electromagnetic radiation decay in time and generate hot carriers in the nanostructure
Implementation Method 3
The plasmonic nanostructured elements form ohmic junctions at the surface of the semiconductor material or at close proximity with the semiconductor material elements
Data Source
AI summary
A nanostructured material system for efficient collection of photo-excited carriers is provided. They system comprises a plurality of plasmonic metal nitride core material elements coupled to a plurality of semiconductor material elements. The plasmonic nanostructured elements form ohmic junctions at the surface of the semiconductor material or at close proximity with the semiconductor material elements. A nanostructured material system for efficient collection of photo-excited carriers is also provided, comprising a plurality of plasmonic transparent conducting oxide core material elements coupled to a plurality of semiconductor material elements. The field enhancement, local temperature increase and energized hot carriers produced by nanostructures of these plasmonic material systems play enabling roles in various chemical processes. They induce, enhance, or mediate catalytic activities in the neighborhood when excited near the resonance frequencies.