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Abstract Porous noble metal nanoparticles have received particular attention recently for their unique optical, thermal, and catalytic functions in biomedicine. However, limited progress has been made to synthesize such porous metallic nanostructures with large mesopores (≥25 nm). Here, a green yet facile synthesis strategy using biocompatible liposomes as templates to mediate the formation of mesoporous metallic nanostructures in a controllable fashion is reported. Various monodispersed nanostructures with well‐defined mesoporous shape and large mesopores (≈ 40 nm) are successfully synthesized from mono‐ (Au, Pd, and Pt), bi‐ (AuPd, AuPt, AuRh, PtRh, and PdPt), and tri‐noble metals (AuPdRh, AuPtRh, and AuPdPt). Along with a successful demonstration of its effectiveness in synthesis of various mesoporous nanostructures, the possible mechanism of liposome‐guided formation of such nanostructures via time sectioning of the synthesis process (monitoring time‐resolved growth of mesoporous structures) and computational quantum molecular modeling (analyzing chemical interaction energy between metallic cations and liposomes at the enthalpy level) is also revealed. These mesoporous metallic nanostructures exhibit a strong photothermal effect in the near‐infrared region, effective catalytic activities in hydrogen peroxide decomposition reaction, and high drug loading capacity. Thus, the liposome‐templated method provides an inspiring and robust avenue to synthesize mesoporous noble metal‐based nanostructures for versatile biomedical applications.
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Oriented Attachment: A Unique Mechanism for the Colloidal Synthesis of Metal Nanostructures
Abstract Rational synthesis of nanostructures with desired properties critically depends on our understanding of the growth mechanism. In addition to the traditional mechanism involving atomic addition, oriented attachment (OA) has received increasing attention in recent years. Employing nanocrystallites as building blocks, OA offers an important route to anisotropic growth, inclusion of defects, and formation of nanostructures with branched morphology. With a focus on metals, here we offer a brief account of recent progress in understanding OA and how it can be adapted for the colloidal synthesis of nanostructures with diverse compositions and morphologies. We start with a discussion on the current understanding of OA based on computational simulations and experimental studies, followed by typical examples of metal nanostructures produced through OA. Finally, we showcase the catalytic and plasmonic applications enabled by those nanostructures, together with perspectives on the challenges and opportunities.
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- Award ID(s):
- 1804970
- PAR ID:
- 10363742
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemNanoMat
- Volume:
- 8
- Issue:
- 3
- ISSN:
- 2199-692X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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