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Spontaneous formation of gold nanostructures in aqueous microdroplets.

ABSTRACT: The synthesis of gold nanostructures has received widespread attention owing to many important applications. We report the accelerated synthesis of gold nanoparticles (AuNPs), as well as the reducing-agent-free and template-free synthesis of gold nanoparticles and nanowires in aerosol microdroplets. At first, the AuNP synthesis are carried out by fusing two aqueous microdroplet streams containing chloroauric acid and sodium borohydride. The AuNPs (~7?nm in diameter) are produced within 60?µs at the rate of 0.24?nm?µs-1. Compared to bulk solution, microdroplets enhance the size and the growth rate of AuNPs by factors of about 2.1 and 1.2?×?105, respectively. Later, we find that gold nanoparticles and nanowires (~7?nm wide and >2000?nm long) are also formed in microdroplets in the absence of any added reducing agent, template, or externally applied charge. Thus, water microdroplets not only accelerate the synthesis of AuNPs by orders of magnitude, but they also cause spontaneous formation of gold nanostructures.

SUBMITTER: Lee JK

PROVIDER: S-EPMC5908806 | biostudies-other | 2018 Apr

REPOSITORIES: biostudies-other

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Spontaneous formation of gold nanostructures in aqueous microdroplets.

Lee Jae Kyoo JK Samanta Devleena D Nam Hong Gil HG Zare Richard N RN

Nature communications 20180419 1

The synthesis of gold nanostructures has received widespread attention owing to many important applications. We report the accelerated synthesis of gold nanoparticles (AuNPs), as well as the reducing-agent-free and template-free synthesis of gold nanoparticles and nanowires in aerosol microdroplets. At first, the AuNP synthesis are carried out by fusing two aqueous microdroplet streams containing chloroauric acid and sodium borohydride. The AuNPs (~7 nm in diameter) are produced within 60 µs at ...[more]

PMID: 29674623

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