Rb2CuX3 Copper Halide Perovskites for Lead-Free Blue Emission

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The development of efficient blue-emitting light-emitting diodes (LEDs) has been hindered by the toxicity and instability of lead-based halides, and existing oxide materials are costly due to rare-earth element dependence and high-temperature synthesis methods.

Innovation Solution

The development of non-lead, thermally stable, and high-efficiency blue-emitting all-inorganic halides using Group 1A elements like K, Rb, and Cs, specifically Rb2CuX3 compounds with a one-dimensional crystal structure, which exhibit record-high photoluminescence quantum yields and can be prepared at room temperature with low toxicity elements.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Power

If lead-based halides are used for blue emission, then emission efficiency is improved, but toxicity and stability worsen

Engineering Contradiction:
Improveemission efficiencyVSAvoidtoxicity
Core Design Contradiction:
PowerVSObject-affected harmful factors

Solution Approach 1:

The patent replaces toxic lead-based materials with inexpensive, non-toxic copper halide perovskites that can be synthesized at room temperature. The use of abundant elements (Cu, Cl, Br, I) instead of rare and toxic lead eliminates environmental harm while maintaining optoelectronic performance for blue emission applications.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

Solution Approach 2:

The patent changes the chemical composition parameters by substituting lead (Pb) with copper (Cu) and adjusting the halide ratio (Cl, Br, I) to tune the bandgap and emission wavelength. This compositional parameter change achieves blue emission (450-480 nm) while eliminating toxicity, resolving the contradiction between emission efficiency and harmful factors.

Inventive Principle:
Principle #35Parameter changes

2Illumination intensity

If oxide materials with rare-earth elements are used, then luminescence performance is improved, but cost increases

Engineering Contradiction:
Improveluminescence performanceVSAvoidcost
Core Design Contradiction:
Illumination intensityVSQuantity of substance

Solution Approach 1:

The patent replaces expensive rare-earth element oxides (e.g., Ce-doped YAG) with inexpensive copper halide perovskites composed of abundant elements. The room-temperature synthesis further reduces manufacturing costs, achieving high luminescence performance without rare-earth dependence and making the material economically viable for commercial applications.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

Solution Approach 2:

The patent extracts and eliminates rare-earth elements from the luminescent material composition, replacing them with common, inexpensive elements like copper and halides. This extraction of expensive components while maintaining luminescence functionality directly addresses the cost problem.

Inventive Principle:
Principle #2Taking out (Extraction)

3Manufacturing precision

If high-temperature synthesis methods are used for oxide materials, then material quality is improved, but manufacturing cost and energy consumption increase

Engineering Contradiction:
Improvematerial qualityVSAvoidsynthesis energy consumption
Core Design Contradiction:
Manufacturing precisionVSUse of energy by stationary object

Solution Approach 1:

The patent changes the synthesis temperature parameter from high-temperature (typically >1000°C for oxides) to room temperature or mild heating conditions for copper halide perovskites. This parameter change maintains crystalline quality and optoelectronic performance while dramatically reducing energy consumption and manufacturing complexity.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent replaces the high-temperature thermal processing mechanism with room-temperature solution-based synthesis or mild annealing. This substitution of the synthesis mechanism eliminates the need for energy-intensive furnaces and high-temperature equipment, reducing both cost and energy consumption while producing high-quality materials.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

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

These materials provide efficient, cost-effective, and environmentally friendly blue emitters with enhanced charge localization and excitonic properties, overcoming the limitations of lead-based halides and oxide materials, suitable for low-cost optoelectronic devices.

Implementation Method 1

exhibit record-high photoluminescence quantum yields

Methodology Applied
Scientific EffectPhotoluminescence: Photoluminescence

Data Source

PatentUS11591516B2Luminescent group 1A copper halides and uses thereof
Publication Date: 2023.02.28 THE BOARD OF RGT UNIV OF OKLAHOMA

AI summary

High photoluminescence, high stability, inorganic perovskite compounds comprising an alkali metal selected from potassium (K), rubidium (Rb), and cesium (Cs); copper (Cu); and at least one halogen selected from chlorine (Cl), bromine (Br), and iodine (I). The perovskites may be free of lead (Pb). The inorganic perovskite compound may be used in an optoelectronic device. The optoelectronic device optionally contains a phosphor such as a blue-emitting phosphor. The inorganic perovskite compound may be used as an anti-counterfeiting nanotaggant applied on or within an object that susceptible to counterfeiting to enable confirmation of an authentic object.