Shuang-Yuan Zhang

Janus Au‐TiO2 Photocatalysts with Strong Localization of Plasmonic Near‐Fields for Efficient Visible‐Light Hydrogen Generation

The first use of non-centrosymmetric Janus Au-TiO(2) photocatalysts in efficient, plasmon-enhanced visible-light hydrogen generation is demonstrated. The intense localization of plasmonic near-fields close to the Au-TiO(2) interface, coupled with optical transitions involving localized electronic states in amorphous TiO(2) brings about enhanced optical absorption and the generation of electron-hole pairs for photocatalysis.

Protein Induces Layer-by-Layer Exfoliation of Transition Metal Dichalcogenides

Here, we report a general and facile method for effective layer-by-layer exfoliation of transition metal dichalcogenides (TMDs) and graphite in water by using protein, bovine serum albumin (BSA) to produce single-layer nanosheets, which cannot be achieved using other commonly used bio- and synthetic polymers. Besides serving as an effective exfoliating agent, BSA can also function as a strong stabilizing agent against reaggregation of single-layer nanosheets for greatly improving their biocompatibility in biomedical applications. With significantly increased surface area, single-layer MoS2 nanosheets also exhibit a much higher binding capacity to pesticides and a much larger specific capacitance. The protein exfoliation process is carefully investigated with various control experiments and density functional theory simulations. It is interesting to find that the nonpolar groups of protein can firmly bind to TMD layers or graphene to expose polar groups in water, facilitating the effective exfoliation of single-layer nanosheets in aqueous solution. The present work will enable to optimize the fabrication of various 2D materials at high yield and large scale, and bring more opportunities to investigate the unique properties of 2D materials and exploit their novel applications.

Synthesis and multiple reuse of eccentric Au@TiO2 nanostructures as catalysts.

In this work, we have synthesized eccentric Au@TiO(2) core-shell nanostructures and demonstrated their multiple reuse in the catalytic reduction of 4-nitrophenol.

Disproportionation for Growing Copper Nanowires and their Controlled Self‐Assembly Facilitated by Ligand Exchange

The coating makes the wire bundle: High-quality free-standing copper nanowires have been successfully produced by disproportionation of Cu(+) in oleylamine. This provides an effective way to prepare high-quality copper nanowires, but also enriches synthetic routes to other nanostructures. These copper nanowires can self-assemble by surface ligand exchange of oleylamine with trioctylphosphine.

Intrinsically Colored and Luminescent Silk

A IO N Silk has been a highly prized material since its discovery a few thousand years ago, with a current annual industrial output of approximately 30 billion US dollars in China alone. [ 1 , 2 ] In silk industry, the outer layer of silk (sericin) needs to be removed in order to use the core of silk (fi broin) that has excellent mechanical properties combined with luster, smoothness, and comfort. To impart color to the fi nished products, silk fi broin is subjected to the dyeing process including steps to remove excess dye molecules and to restore the properties of silk that are altered due to the harsh conditions involved in the process. [ 3 ] Here, we demonstrate an in vivo uptake of dyes into domesticated silkworms, leading to the direct production of intrinsically colored silk by the silkworms. The biological incorporation of dyes into silk fi broin is a greener method of producing colored silk because it eliminates the need for an external dyeing process, along with the resources (water, energy, additional chemicals) and post-treatments associated with it. A series of fl uorescent dyes were successfully used as model compounds to investigate and understand their selective uptake into fi broin or sericin through fl uorescence imaging and spectroscopic quantifi cation. A better understanding of the molecular factors that determine the uptake of substances into silk fi broin was established to select and design appropriate molecules for producing intrinsically colored and luminescent silk fi broin, i.e., by controlling the structure-dependent hydrophobicity and self-assembly capability of these molecules. In addition to the production of intrinsically colored silk for textile applications, the current work also results in a biocompatible and luminescent silk scaffold that allows better visualization of cells and monitoring of the scaffold performance over time. When applied to other compounds with similar molecular properties, this process can potentially lead to functional silk for various biomedical applications including tissue engineering and bioelectronic, bio-optic, and biomicrofl uidic devices. [ 4–6 ]

Temperature and chemical bonding-directed self-assembly of cobalt phosphide nanowires in reaction solutions into vertical and horizontal alignments.

The preparation of vertically or horizontally aligned self-assemblies of CoP nanowires is demonstrated for the first time by aging them in the reaction solution for a sufficient time at 20 or 0 °C. This strategy opens up a way for exploring the controlled self-assembly of various highly anisotropic nanostructures into long-range ordered structures with collective properties.

Ternary cobalt-iron phosphide nanocrystals with controlled compositions, properties, and morphologies from nanorods and nanorice to split nanostructures.

Structural phase-controlled formation of binary Co(2)P and CoP nanocrystals is achieved by reacting cobalt(II) oleate with trioctylphosphine. In the absence of oleylamine, Co(2)P nanowires are formed at both 290 and 320 °C. In the presence of oleylamine, Co(2)P nanorods are formed at 290 °C, and CoP nanorods are formed at 320 °C. With the simultaneous reaction of iron(III) oleate and cobalt(II) oleate with trioctylphosphine in the presence of oleylamine, ternary Co(2)P-type cobalt-iron phosphide nanostructures are produced at both 290 and 320 °C, corresponding to rice-shaped Co(1.5)Fe(0.5)P nanorods and split Co(1.7)Fe(0.3)P nanostructures, respectively. The controlled incorporation of iron into cobalt phosphide can alter the magnetic properties from paramagnetic binary Co(2)P to ferromagnetic Co(2)P-type ternary cobalt-iron phosphide nanostructures. Meanwhile, the time-dependent morphological evolution from small nanodots/nanorods, through seeded growth to unique split nanostructures is demonstrated in one-pot reaction at 320 °C.

Convenient purification of gold clusters by co-precipitation for improved sensing of hydrogen peroxide, mercury ions and pesticides

An effective separation process is developed to remove free protein from the protein-protected gold clusters via co-precipitation with zinc hydroxide on their surface. After dialysis, the purified clusters exhibit an enhanced fluorescence for improved sensitive detection and selective visualization.

Destabilization of Gold Clusters for Controlled Nanosynthesis: From Clusters to Polyhedra

A precisely controlled destabilization of gold thiolate clusters is demonstrated to grow 12 {110}-faceted gold dodecahedra with greatly enhanced catalytic capability, and reveal the growth mechanism by DFT simulations. This greatly advances our understanding of nanocrystal growth and opens a new window for controlling the dissociation of clusters to produce nanocrystals with specific shapes.

Optimized production of copper nanostructures with high yields for efficient use as thermal conductivity-enhancing PCM dopant

Copper nanostructures with a high yield are synthesized by a controlled disproportionation of CuCl in oleylamine reaction medium without the involvement of strong reducing agents adopted in conventional approaches. The highest copper yield (50%), a maximum theoretical value, is obtained by optimizing both the initial amount of CuCl added to the reaction medium and the reaction temperature. A potential use of the copper nanostructures in greatly enhancing thermal conductivity of a hydrated CaCl2·6H2O salt phase change material (PCM) is further demonstrated. A high thermal conductivity enhancement of the PCM (>50%) is achieved by doping a small amount (<0.2 wt%) of the copper nanostructures. The great enhancement with the use of a very small amount of the copper nanostructures makes the doping cost-effective for practical thermal energy storage applications.