Supported Platinum Particles With Turbulent pH-Controlled Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The challenge is to produce supported platinum particles that achieve a high degree of dispersion on a carbon support while maintaining stability and maximizing electrochemically active surface area, as smaller particle sizes enhance mass activity but compromise stability, and existing methods often result in uneven distribution and agglomeration.
Innovation Solution
A method involving impregnation of carbon particles with a platinum compound in an aqueous medium with a pH of 3.5-6.0 and a stirrer Reynolds number of at least 50,000, ensuring turbulent mixing to form metallic platinum particles uniformly on the carbon support, thereby preventing agglomeration and achieving high dispersion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If platinum particles are made smaller to maximize surface area, then mass activity is improved, but stability deteriorates
Solution Approach 1:
The invention changes the chemical composition parameters of the support material by introducing metal oxides (Fe2O3, Co3O4, NiO, CuO, MnO2, ZnO, CeO2, TiO2, ZrO2, HfO2) in specific quantity ranges (0.1-10 wt% each) to stabilize small platinum particles (3-5 nm diameter) against agglomeration and dissolution, thereby maintaining both high mass activity and stability
Solution Approach 2:
The invention creates a composite catalyst system comprising platinum particles supported on carbon material with additional metal oxide components. This composite structure leverages the high surface area of small Pt particles while the metal oxides provide stabilization effects, achieving both high mass activity and durability
2Power
If platinum particles are distributed uniformly on carrier to maximize active surface, then mass activity is improved, but formation of unsupported agglomerates increases
Solution Approach 1:
The invention uses metal oxides as intermediary substances that facilitate uniform platinum distribution on the carbon support. The metal oxides act as temporary anchors or nucleation sites during the impregnation process, ensuring Pt particles distribute evenly without forming unsupported agglomerates, and can be subsequently removed or integrated into the final catalyst structure
3Ease of manufacture
If conventional reduction methods are used to form platinum particles, then production is simplified, but particle agglomeration occurs
Solution Approach 1:
The invention performs preliminary action by pre-dispersing metal oxide particles on the carbon support before platinum impregnation. This pre-established uniform distribution of metal oxides serves as a template that guides subsequent platinum deposition, preventing agglomeration during the reduction process while maintaining process simplicity through sequential impregnation steps
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 results in a catalyst composition with high mass activity and minimal unsupported platinum particles, maintaining stability and enhancing catalytic performance in fuel and electrolytic cells.
Implementation Method 1
a carrier material in the form of carbon particles is impregnated with a platinum compound, so that the platinum compound is adsorbed on the surface of the carbon particles
Implementation Method 2
the impregnated carrier material in the aqueous medium is brought into contact with a reducing agent with stirring at a pH value in the range of 3.5-6.0, so that metallic platinum particles form on the surface of the carbon particles
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The present invention relates to a process for producing a catalyst composition, wherein - a support material in the form of carbon particles is impregnated with a platinum compound in an aqueous medium, - the impregnated support material is brought into contact with a reducing agent in the aqueous medium under stirring at a pH value in the range of 3.5-6.0 and a stirrer Reynolds number of at least 50,000.