title: Reduction-resistant and reduction-catalytic double-crown nickel nanoclusters.
abstract: In this work, an attempt to synthesize zero-valent Ni nanoclusters using the Brust method resulted in an unexpected material, Ni₆(SCH₂CH₂Ph)₁₂, which is a nanoscale Ni(ii)-phenylethanethiolate complex and a hexameric, double-crown-like structure, as determined by a series of characterizations, including mass spectrometry (MS), thermal gravimetric analysis (TGA), single-crystal X-ray diffraction (XRD), and X-ray photoelectron spectrometry (XPS). An interesting finding is that this complex is resistant to aqueous BH4(-). Investigations into other metal-phenylethanethiolate and Ni-thiolate complexes reveal that this property is not universal and appears only in complexes with a double-crown-like structure, indicating the correlation between this interesting property and the complexes' special structure. Another interesting finding is that the reduction-resistant Ni₆(SCH₂CH₂Ph)₁₂ exhibits remarkably higher catalytic activity than a well-known catalyst, Au₂₅(SCH₂₂Ph)₁₈, toward the reduction of 4-nitrophenol at low temperature (e.g., 0 °C). This work will help stimulate more research on the properties and applications of less noble metal nanoclusters.
authors.affiliation: Key Laboratory of Materials Physics, Anhui Key Laboratory of Nanomaterials and Nanostructures, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei, 230031, China. zkwu@issp.ac.cn.
authors.forename: Min
authors.initials: M
authors.lastname: Zhu
authors.forename: Shiming
authors.initials: S
authors.lastname: Zhou
authors.forename: Chuanhao
authors.initials: C
authors.lastname: Yao
authors.forename: Lingwen
authors.initials: L
authors.lastname: Liao
authors.forename: Zhikun
authors.initials: Z
authors.lastname: Wu