The field of nanotechnology has shown immense potential in various applications, including catalysis, optics, electronics, and biomedicine. Bimetallic nanoparticles have garnered attention due to their superior properties compared to single-component nanoparticles. The ability to precisely control the size, shape, composition, and spatial arrangement of these nanoparticles is crucial for optimizing their performance in specific applications.
However, the vast parameter space, including the size, structure, and composition of nanoparticles, presents significant challenges in discovering the optimal nanoparticles for sensitive reactions. High-throughput synthesis methods that can control the composition and spatial arrangement of nanoparticles are highly desirable to accelerate the discovery of new materials.
Current approaches to synthesizing bimetallic nanoparticles face several limitations. Conventional methods, such as combinatorial sputtering, optical ablation, and dip-pen nanolithography, often lack the ability to provide precise spatial control over the nanoparticles on the electrode. Additionally, these methods require multistep processes or the preparation of precursor solutions with specific mole fractions, limiting on-demand control of the alloy composition at specific locations. Furthermore, the use of ligands to stabilize nanoparticles can block active sites, reducing their effectiveness as electrocatalysts.
Electrodeposition offers a promising alternative, allowing real-time control over the nucleation and growth processes. However, challenges such as the stochastic nature of nucleation and low throughput hinder its effectiveness.
Scanning electrochemical cell microscopy (SECCM) has emerged as a potential solution, offering high spatial resolution and precise control over nanoparticle synthesis, yet it still faces hurdles in achieving continuous compositional control and high-throughput synthesis.
The technology described involves a novel methodology for synthesizing bimetallic alloy nanoparticle arrays with precise control over their composition and spatial arrangement. Utilizing a dual-channel nanopipette, the process allows for fine-tuning of the electrodeposition rate of each element within the nanoparticle, ensuring accurate control over the final composition.
The technique is validated through finite element simulation, electrochemical, and elemental analyses. The scope of nanoparticles that can be synthesized includes combinations such as Cu−Ag, Cu−Pt, Au−Pt, Cu−Pb, and Co−Ni. Additionally, the method enables surface patterning with precise control over the location and composition of each pixel. Integration of this synthesis method with scanning electrochemical cell microscopy (SECCM) allows for rapid screening of electrocatalysts, making it broadly applicable for synthesizing metal nanoparticles that can be electrodeposited, which is crucial for developing automated synthesis and screening systems for accelerated material discovery in electrocatalysis.
This technology differentiates itself through its high precision and control in nanoparticle synthesis, addressing the complexities associated with the large parameter space of size, structure, composition, and spatial arrangement.
Traditional methods often lack the ability to control the spatial positioning of nanoparticles on the electrode or require multistep processes and specific precursor preparations, limiting on-demand composition control. In contrast, the dual-channel nanopipette method allows for real-time, in-situ control of the nanoparticle composition by adjusting the solution composition in the SECCM droplet cell via migration and electroosmotic flow.
This approach not only simplifies the synthesis process but also enhances the homogeneity and uniformity of the nanoparticles, even at non-equilibrium states. The ability to create detailed surface patterns and the potential for high-throughput synthesis and screening of electrocatalysts further underscore its utility in accelerating materials discovery and advancing applications in catalysis, optics, electronics, and biomedicine.
PCT application serial number US2024/029566, “Nanoparticle Array and Method for the Manufacture and Use Thereof.” https://worldwide.espacenet.com/patent/search?q=pn%3DWO2024249089A2