One-dimensional (1D) boron nanostructures are very potential for nanoscale electronic devices since their physical properties including electric transport and field emission have been found very ...promising as compared to other well-developed 1D nanomaterials. In this article, we review the current progress that has been made on 1D boron nanostructures in terms of theoretical prediction, synthetic techniques, characterizations and potential applications. To date, the synthesis of 1D boron nanostructures has been well-developed. The popular structures include nanowires, nanobelts, and nanocones. Some of these 1D nanostructures exhibited improved electric transport properties over bulk boron materials as well as promising field emission properties. By current experimental findings, 1D boron nanostructures are promising to be one of core materials for future nanodevices. More efforts are expected to be made in future on the controlled growth of 1D boron nanostructures and tailoring their physical properties.
We review the current progress that has been made on novel 1D boron crystalline nanostructures including theoretical prediction, synthetic techniques, characterizations, and potential applications.
Two-dimensional (2D) materials with defects are desired for catalysis after the adsorption of monodispersed noble metal atoms. High-performance catalysts with the absolute value of Gibbs free energy ...(∣∆
G
H
∣) close to zero, is one of the ultimate goals in the catalytic field. Here, we report the formation of monolayer titanium selenide (TiSe
2
) with line defects. The low-temperature scanning tunneling microscopy/spectroscopy (STM/S) measurements revealed the structure and electronic states of the line defect. Density functional theory (DFT) calculation results confirmed that the line defects were induced by selenium vacancies and the STM simulation was in good agreement with the experimental results. Further, DFT calculations show that monolayer TiSe
2
with line defects have good catalytic activity for hydrogen evolution reaction (HER). If the defects are decorated with single Pt atom, the HER catalytic activity will be enhanced dramatically (∣∆
G
H
∣ = 0.006 eV), which is much better than Pt metal (∣∆
G
H
∣ = 0.09 eV). Line defects in monolayer TiSe
2
/Au(111) provide a wonderful platform for the design of high-performance catalysts.
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•Vertically standing graphene sheets were grown on indium tin oxide glass.•The lateral size of the graphene sheets was affected by the growth temperature.•The effect of graphene sheet ...size to the field-emission behavior was investigated.
Vertically standing graphene sheets (VSGs) were successfully grown on indium tin oxide (ITO) glass through plasma enhanced chemical vapor deposition system. The lateral size of the graphene sheets was evidently affected by the growth temperature. The VSGs with smaller sheet size were obtained at 600°C than at 500°C. The dependence of the field-emission behavior of VSGs grown on ITO glass (VSGs/ITO) on the sheet size was investigated. The VSGs/ITO films with smaller sheet size possessed a higher field-enhancement factor and a lower turn-on field, which was proposed to be attributed to more field-emission sites and better electrical conductivity.
Doping graphene with boron has been difficult because of high reaction barriers. Here, we describe a low-energy reaction route derived from first-principles calculations and validated by experiments. ...We find that a boron atom on graphene on a ruthenium(0001) substrate can replace a carbon by pushing it through, with substrate attraction helping to reduce the barrier to only 0.1 eV, implying that the doping can take place at room temperature. High-quality graphene is grown on a Ru(0001) surface and exposed to B2H6. Scanning tunneling microscopy/spectroscopy and X-ray photoelectron spectroscopy confirmed that boron is indeed incorporated substitutionally without disturbing the graphene lattice.
Abstract
Water electrolysis is a promising technique for carbon neutral hydrogen production. A great challenge remains at developing robust and low‐cost anode catalysts. Many pre‐catalysts are found ...to undergo surface reconstruction to give high intrinsic activity in the oxygen evolution reaction (OER). The reconstructed oxyhydroxides on the surface are active species and most of them outperform directly synthesized oxyhydroxides. The reason for the high intrinsic activity remains to be explored. Here, a study is reported to showcase the unique reconstruction behaviors of a pre‐catalyst, thiospinel CoFe
2
S
4
, and its reconstruction chemistry for a high OER activity. The reconstruction of CoFe
2
S
4
gives a mixture with both Fe–S component and active oxyhydroxide (Co(Fe)O
x
H
y
) because Co is more inclined to reconstruct as oxyhydroxide, while the Fe is more stable in Fe–S component in a major form of Fe
3
S
4
. The interface spin channel is demonstrated in the reconstructed CoFe
2
S
4
, which optimizes the energetics of OER steps on Co(Fe)O
x
H
y
species and facilitates the spin sensitive electron transfer to reduce the kinetic barrier of O–O coupling. The advantage is also demonstrated in a membrane electrode assembly (MEA) electrolyzer. This work introduces the feasibility of engineering the reconstruction chemistry of the precatalyst for high performance and durable MEA electrolyzers.
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