Decoupling Intrinsic Metal Ion Reduction Rates from Structural Outcomes in Multimetallic Nanoparticles
Jacob H Smith1, Qi Luo1, Shelby L Millheim1
1Department of Chemistry, University of Pittsburgh, 219 Parkman Avenue, Pittsburgh, Pennsylvania 15260, United States.
Journal of the American Chemical Society
|December 9, 2024
Summary
Synthesizing multimetallic nanoparticles with controlled structure and composition is now possible by manipulating precursor concentrations. This method overcomes challenges posed by differing metal reduction rates, enabling precise nanoparticle design.
Area of Science:
- Materials Science
- Nanotechnology
- Chemistry
Background:
- Controlling stoichiometry and atom arrangement in multimetallic nanoparticles is difficult, especially with precursors having varied reduction kinetics.
- Traditional methods often result in phase-segregated structures due to intrinsic differences in metal precursor reduction rates.
Purpose of the Study:
- To demonstrate a method for manipulating relative metal precursor reduction kinetics independently of their intrinsic rates.
- To develop a quantitative model predicting optimal conditions for synthesizing multimetallic nanoparticles with controlled outcomes.
- To achieve precise stoichiometric and structural control in nanoparticle synthesis.
Main Methods:
- Modulating instantaneous metal cation precursor concentrations by adjusting precursor addition rates.
- Developing and applying a quantitative model to predict metal ion reduction rates based on precursor addition rates.
- Experimentally synthesizing core@shell and alloyed nanoparticles in bimetallic (Au-Pd, Au-Pt) and quinary (Co, Ni, Cu, Pd, Pt) systems.
Main Results:
- Demonstrated independent control over relative reduction kinetics by adjusting precursor addition rates.
- Successfully synthesized multimetallic nanoparticles with precise stoichiometric and structural control.
- Validated the predictive model across various bimetallic and quinary systems.
Conclusions:
- The developed approach enables the design of nanoparticle architectures irrespective of intrinsic metal ion reduction potential differences.
- Precise stoichiometric and structural control can be achieved in multimetallic nanoparticle synthesis.
- This method offers a versatile strategy for creating advanced nanomaterials.
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