Silver-Zirconium Oxide Porous Clusters for Alkaline Electrode Stability

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Silver catalysts used in alkaline electrolyte systems face significant dissolution issues due to the formation of silver oxides, leading to reduced electrode performance and stability, especially in air or oxygen electrodes for batteries and fuel cells.

Innovation Solution

The development of silver-based catalysts with porous clusters of silver particles promoted by zirconium oxide, where crystalline ZrO2 particles are integrated into the pores of silver primary particles, enhancing stability and resistance to dissolution.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If silver catalyst is used in alkaline electrolyte systems, then catalytic activity for oxygen electrodes is achieved, but dissolution occurs due to silver oxide formation reducing stability and performance

Engineering Contradiction:
Improvecatalyst stabilityVSAvoidsilver dissolution
Core Design Contradiction:
ReliabilityVSLoss of substance

Solution Approach 1:

Zirconium oxide serves as a protective intermediary layer that coats the silver catalyst particles, preventing direct contact between silver and the alkaline electrolyte. This intermediary layer blocks the oxidation pathway while allowing catalytic function to proceed, thereby preventing silver dissolution without compromising catalytic activity.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The invention creates a composite catalyst structure combining silver with zirconium oxide, where the two materials work synergistically. The silver provides catalytic activity for oxygen reduction/evolution reactions, while the zirconium oxide component provides chemical stability and resistance to dissolution in alkaline environments.

Inventive Principle:
Principle #40Composite materials

2Productivity

If silver oxide forms during anodic oxidation, then electrochemical reactions proceed, but catalyst surface area decreases due to precipitation and roughening

Engineering Contradiction:
Improveelectrochemical reaction rateVSAvoidcatalyst surface area
Core Design Contradiction:
ProductivityVSArea of stationary object

Solution Approach 1:

The zirconium oxide coating is applied in advance to prevent the harmful formation of silver oxide and subsequent precipitation. By establishing this protective barrier before electrochemical reactions begin, the system prevents the roughening and surface area loss that would otherwise occur during anodic oxidation cycles.

Inventive Principle:
Principle #9Preliminary anti-action

Solution Approach 2:

The invention converts the potential harm of silver oxidation into a benefit by using zirconium oxide to control the oxidation process. Instead of allowing uncontrolled silver oxide formation that leads to precipitation and surface degradation, the zirconium oxide mediates the electrochemical reactions while maintaining surface integrity.

Inventive Principle:
Principle #22Blessing in disguise (Convert harm into benefit)

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

The silver-zirconium oxide catalysts demonstrate improved stability, maintaining surface area and performance under open circuit voltage and bi-functional mode operations, leading to longer-lasting and more robust electrodes in alkaline electrolyte systems.

Implementation Method 1

crystalline particles of zirconium oxide (ZrO2), wherein at least a portion of the crystalline particles of ZrO2 is located in pores formed by a surface of the plurality of primary particles

Methodology Applied
Scientific EffectPrecipitation: Precipitation

Implementation Method 2

porous clusters of silver particles, each cluster of the clusters including: (a) a plurality of primary particles of silver

Methodology Applied
Scientific EffectAdsorption: Adsorption

Data Source

PatentEP2684602B1Porous clusters of silver powder promoted by zirconium oxide for use as a catalyst in gas diffusion electrodes, and uses thereof
Publication Date: 2016.06.01 BAR ILAN UNIV
  • EP2684602B1 patent drawingFigure 1~2
  • EP2684602B1 patent drawingFigure 3A~3B
  • EP2684602B1 patent drawingFigure 4

AI summary

An air electrode comprising a catalyst comprising a plurality of porous clusters of silver particles, each cluster including a plurality of primary particles of silver and crystalline particles of zirconium oxide (ZrO2), wherein at least a portion of said crystalline particles of ZrO2 is located in pores formed by a surface of said plurality of primary particles; a water-repellant polymer; a silver-coated current collector; and a porous hydrophobic film, wherein said catalyst, said water-repellent polymer and said current collector are located on a single broad face of said porous hydrophobic film.