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Abstract Hierarchical plasmonic biomaterials constructed from small nanoparticles (NPs) that combine into larger micron‐sized structures exhibit unique properties that can be harnessed for various applications. Using diffusion‐limited aggregation (DLA) and defined peptide sequences, we developed fractal silver biomaterials with a Brownian tree structure. This method avoids complex redox chemistry and allows precise control of interparticle distance and material morphology through peptide design and concentration. Our systematic investigation revealed how peptide charge, length, and sequence impact biomaterial morphology, confirming that peptides act as bridging motifs between particles and induce coalescence. Characterization through spectroscopy and microscopy demonstrated that arginine‐based peptides are optimal for fractal assembly based on both quantitative and qualitative measurements. Additionally, our study of diffusion behavior confirmed the effect of particle size, temperature, and medium viscosity on nanoparticle mobility. This work also provides insights into the facet distribution in silver NPs and their assembly mechanisms, offering potential advancements in the design of materials for medical, environmental, and electronic applications.
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Investigating Particle Size‐Dependent Redox Kinetics and Charge Distribution in Disordered Rocksalt Cathodes
Abstract Understanding how various redox activities evolve and distribute in disordered rocksalt oxides (DRX) can advance insights into manipulating materials properties for achieving stable, high‐energy batteries. Herein, the authors present how the reaction kinetics and spatial distribution of redox activities are governed by the particle size of DRX materials. The size‐dependent electrochemical performance is attributed to the distinct cationic and anionic reaction kinetics at different sizes, which can be tailored to achieve optimal capacity and stability. Overall, the local charged domains in DRX particles display random heterogeneity caused by the isotropic delithiation pathways. Owing to the kinetic limitation, the micron‐sized particles exhibit a holistic “core‐shell” charge distribution, whereas sub‐micron particles show more uniform redox reactions throughout the particles and ensembles. Sub‐micron DRX particles exhibit increasing anionic redox activities yet inferior cycling stability. In summary, engineering particle size can effectively modulate how cationic and anionic redox activities evolve and distribute in DRX materials.
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- Award ID(s):
- 2045570
- PAR ID:
- 10366668
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 32
- Issue:
- 17
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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