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Surfactant-free synthesis of porous Au by a urea complex.

ABSTRACT: We report a facile surfactant-free synthetic method to obtain porous and hollow Au nanoparticles using only urea and HAuCl₄·4H₂O as precursors at 200 °C. The formation mechanism was investigated through X-ray diffraction, scanning electron microscopy, and high-resolution transmission electron microscopy. Moreover, the prepared Au nanocrystals present superior catalytic performance for the reduction of 4-nitrophenol in comparison with solid Au nanoparticles. The catalytic efficiency of porous and hollow Au was nearly 6 times higher than that of Au nanoparticles. Furthermore, the porous and hollow Au maintained excellent stability even after 10 catalytic cycles. Therefore, the as-synthesized porous Au nanoparticles will have potential applications in organic catalysis, biosensing, drug delivery, water pollutant removal, and so on.

SUBMITTER: Zhang Q

PROVIDER: S-EPMC9067248 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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Surfactant-free synthesis of porous Au by a urea complex.

Zhang Qiang Q Zang Biao B Wang Shaozhen S

RSC advances 20190726 40

We report a facile surfactant-free synthetic method to obtain porous and hollow Au nanoparticles using only urea and HAuCl<sub>4</sub>·4H<sub>2</sub>O as precursors at 200 °C. The formation mechanism was investigated through X-ray diffraction, scanning electron microscopy, and high-resolution transmission electron microscopy. Moreover, the prepared Au nanocrystals present superior catalytic performance for the reduction of 4-nitrophenol in comparison with solid Au nanoparticles. The catalytic ef ...[more]

PMID: 35514500

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