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The influences of synthesis parameters on the mean diameter and diameter distribution of as-grown single-wall carbon nanotubes (SWCNTs) with chemical vapor deposition (CVD) using the mist flow method have been investigated in detail with Raman spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). We found that CVD reaction temperature and flow rate play an essential role in controlling the mean diameter and the quality of as-grown SWCNTs. Furthermore, we found that the carbon supply kinetics can be a dominant factor to determine the diameter of as-grown SWCNTs in the present mist flow method. Under a different combination of various parameters, the mean diameter of SWCNTs can be varied from 0.9 nm to 1.5 nm controllably.

Antimony-based materials possess high theoretical capacities and suitable potential, which could be promising anode materials for sodium-ion batteries (SIB). However, poor stabilities and sluggish kinetics are drawbacks. Building heterojunction is an ideal method to solve these issues. Its unique structure develops internal electric fields spontaneously to boost the charge transport and relieve stress. Nevertheless, the controllable preparation of face-to-face (2D) heterojunctions is still hard-pressed. Herein, ${\mathrm{\text{Sb}}}_2{\mathrm{\text{Te}}}_3$–$\mathrm{\text{Te}}$ nanoheterojunctions, which consist of two-dimensional ${\mathrm{\text{Sb}}}_2{\mathrm{\text{Te}}}_3$–$\mathrm{\text{Te}}$ nanoblades attached to a one-dimensional Te nanorod, are fabricated through a two-step solvothermal method. Among that, the density of nanoblades is adjustable through the engineering feed ratio. When employed as anodes for SIBs, ${\mathrm{\text{Sb}}}_2{\mathrm{\text{Te}}}_3$–$\mathrm{\text{Te}}$ nanoheterojunctions display a reversible capacity of 463.2mAhg${}^{-1}$ at 100mAg${}^{-1}$. Even a capacity of 305.5mAhg${}^{-1}$ remains after 1000 cycles under a high current of 1.5Ag${}^{-1}$. Moreover, the density functional theory (DFT) calculations also identify the high conductivity of heterojunction. This work offers an effective way to design the structures and properties of heterojunctions, further expanding their application range.

Nowadays, nanogap-nanopore devices have attracted widely concerns for its potential application in the third generation DNA sequencing. However, an effective universal method to fabricate nanogap-nanopore device is still needed to overcome the low efficiency problem in fabrication technology. In this paper, wafer-lever Au nanogap-nanopore was fabricated by NEMS technology successfully. Suspended sandwich structure (SiN-Au nanowire-SiO₂, 100nm/20nm/200nm thick) was demonstrated, which can isolate Au nanowire and salt solution effectively. Moreover, this thin nano structure made Au nanogap-nanopore milling much easier with the help of focused ion beam (FIB) in a controllable way. Since the whole manufacture process was achieved in wafer-lever, this method made Au nanogap-nanopore in DNA sequencing more convenient.