Applications of the non-line-of-sight vapor deposition techniques, such as chemical vapor deposition (CVD) and atomic layer deposition (ALD), offer unique opportunities to produce well-defined high ...surface area current collectors, thin films or various nanostructures of active (ion-storage) materials, protective coatings, solid electrolytes and improved separators. These features hold significant promise for solving emerging issues in advanced LiBs and supercapacitors. This paper reviews recent developments and applications of CVD and ALD for these energy storage devices, providing selected examples and outlining critical challenges for further exploration.
Large-scale graphene electronics requires lithographic patterning of narrow graphene nanoribbons for device integration. However, conventional lithography can only reliably pattern approximately ...20-nm-wide GNR arrays limited by lithography resolution, while sub-5-nm GNRs are desirable for high on/off ratio field-effect transistors at room temperature. Here, we devised a gas phase chemical approach to etch graphene from the edges without damaging its basal plane. The reaction involved high temperature oxidation of graphene in a slightly reducing environment in the presence of ammonia to afford controlled etch rate (less than or approximately 1 nm min(-1)). We fabricated approximately 20-30-nm-wide graphene nanoribbon arrays lithographically, and used the gas phase etching chemistry to narrow the ribbons down to <10 nm. For the first time, a high on/off ratio up to approximately 10(4) was achieved at room temperature for field-effect transistors built with sub-5-nm-wide graphene nanoribbon semiconductors derived from lithographic patterning and narrowing. Our controlled etching method opens up a chemical way to control the size of various graphene nano-structures beyond the capability of top-down lithography.
Heteroatom-doped carbon materials (HDCMs) have been widely studied as some of the most prominent material candidates for use in a wide range of applications, such as batteries, supercapacitors (SCs), ...and the oxygen reduction reaction (ORR). Over the past few years, various metal-free heteroatom-doped carbon composites have been developed
via
integrating different heteroatoms into carbon with different nanostructures, from single-atom doping (N, P, B, S,
etc.
) to multiple heteroatom doping (N/P/S, N/S/B,
etc.
). For the first time, this review comprehensively analyzes the relevant features of HDCMs used in batteries, SCs, and the ORR, and provides guidance for the design of more efficient materials. By controlling the content and types of heteroatom-containing reagents, not only the physical and chemical properties of the material can be adjusted, but also the specific surface area and pore volume can be increased
via
controlling the morphology, thereby enhancing the electrochemical performance of the material. Subsequently, this review summarizes the developments and the history of HDCMs, including synthesis methods, the relationship between doping (doping position and content) and performance, reaction mechanisms, and evaluations of systems. In addition, the important role of oxygen doping is raised and discussed, to remind researchers not to ignore the role of oxygen in improving material properties. Finally, future developments and challenges relating to key technologies in this thriving field are also discussed in this report.
Heteroatom-doped carbon materials (HDCMs) have been widely studied as some of the most prominent material candidates for use in a wide range of applications, such as batteries, supercapacitors (SCs), and the oxygen reduction reaction (ORR).
Dilated convolutions support expanding receptive field without parameter exploration or resolution loss, which turn out to be suitable for pixel-level prediction problems. In this paper, we propose ...multiscale single image super-resolution (SR) based on dilated convolutions. We adopt dilated convolutions to expand the receptive field size without incurring additional computational complexity. We mix standard convolutions and dilated convolutions in each layer, called mixed convolutions, i.e., in the mixed convolutional layer, and the feature extracted by dilated convolutions and standard convolutions are concatenated. We theoretically analyze the receptive field and intensity of mixed convolutions to discover their role in SR. Mixed convolutions remove blind spots and capture the correlation between low-resolution (LR) and high-resolution (HR) image pairs successfully, thus achieving good generalization ability. We verify those properties of mixed convolutions by training 5-layer and 10-layer networks. We also train a 20-layer deep network to compare the performance of the proposed method with those of the state-of-the-art ones. Moreover, we jointly learn maps with different scales from a LR image to its HR one in a single network. Experimental results demonstrate that the proposed method outperforms the state-of-the-art ones in terms of PSNR and SSIM, especially for a large-scale factor.
Triple-negative breast cancer (TNBC), a complex and highly aggressive subtype of breast cancer, generally has the poorest clinical outcome, there is a pressing need for more effective therapeutic ...strategies. Immune checkpoint inhibitors against programmed death 1/programmed death ligand 1 (PD1/PDL1) have revolutionized treatment of several solid tumours, such as non-small cell lung carcinoma (NSCLC), renal, malignant melanoma. However, no checkpoint inhibitors were previously approved for the treatment of TNBC. So far, very limited data have reported PDL1 (SP142) expression and its relationship with clinicopathological behaviors and survival in TNBC.
PD-L1(SP142) immunohistochemistry was performed on 223 TNBC cases and assessed in tumour cells(TC) as well as tumor-infiltrating lymphocytes(TILs).The relationships between PD-L1 expression and clinicopathological characteristic both in TC and TILs. Futhermore,we also explored the effect of PD-L1 expression on prognosis as illustrated by overall survival(OS).
PD-L1 expression was detected in both tumor cells and TILs at a ratio of 8.5 % and 25.1 % respectively. PD-L1 expression in TILs was related to histological grade and abundance of TILs. Tumor cell expression of PD-L1 was not associated with outcome. While PD-L1 expression in TILs and lymphnode transfer were associated with a poor outcome, and PD-L1 expression was an independently prognostic of overall survival (OS) (HR = 0.867, P = 0.029).
PD-L1 expression in TILs, but not in tumor cells, was a poor prognostic factor in TNBC. These data provide further impetus for assessing immunotherapy in TNBC, in view of the clinical significance of the expression of PD-L1 (SP142) in TNBC.
Mimicking human skin's functions to develop electronic skins has inspired tremendous efforts in design and synthesis of novel soft materials with simplified fabrication methods. However, it still ...remains a great challenge to develop electronically conductive materials that are both stretchable and self‐healable. Here it is demonstrated that a ternary polymer composite comprised of polyaniline, polyacrylic acid, and phytic acid can exhibit high stretchability (≈500%) and excellent self‐healing properties. The polymer composite with optimized composition shows an electrical conductivity of 0.12 S cm−1. On rupture, both electrical and mechanical properties can be restored with ≈99% efficiency in a 24 h period, which is enabled by the dynamic hydrogen bonding and electrostatic interactions. It is further shown that this composite is both strain and pressure sensitive, and therefore can be used for fabricating strain and pressure sensors to detect a variety of mechanical deformations with ultrahigh sensitivity. The sensitivity and sensing range are the highest among all of the reported self‐healable piezoresistive pressure sensors and even surpass most flexible mechanical sensors. Notably, this composite is prepared via a solution casting process, which potentially allows for large‐area, low‐cost fabrication electronic skins.
Artificial skin: mimicking human skin's functions to develop skin‐like electronics has inspired tremendous efforts in developing novel soft materials. It is shown that a ternary polymer composite comprised of polyaniline, polyacrylic acid, and phytic acid can exhibit high stretchability (≈500%) and excellent self‐healing properties for electronic skin applications with ultrahigh sensitivity.
We developed a chemical route to produce graphene nanoribbons (GNR) with width below 10 nanometers, as well as single ribbons with varying widths along their lengths or containing lattice-defined ...graphene junctions for potential molecular electronics. The GNRs were solution-phase-derived, stably suspended in solvents with noncovalent polymer functionalization, and exhibited ultrasmooth edges with possibly well-defined zigzag or armchair-edge structures. Electrical transport experiments showed that, unlike single-walled carbon nanotubes, all of the sub-10-nanometer GNRs produced were semiconductors and afforded graphene field effect transistors with on-off ratios of about 10⁷ at room temperature.
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•The paper based microfluidic platform provided a simple, robust and user-friendly way for multiplexed detection Cu2+ and Hg2+ ions.•This method can realize the liquid phase of ...QDs@IIPs being transferred to the solid glass fiber paper and improve the portability of the device.•The real samples were successfully analyzed with good sensitivity, selectivity and reliability.
In this study, a novel three-dimensional (3D) origami ion imprinted polymers microfluidic paper-based chip device for specific, sensitive and multiplexed detection of Cu2+ and Hg2+ ions has been proposed. In this device, the surface of the paper was activated by grafting with CdTe QDs through amino processing and formation of Cu2+ or Hg2+ IIPs and CdTe QDs complex that led to fluorescence quenching of QDs because the photo luminescent energy of QDs could be delivered to the complex. This method can realize the liquid phase of QDs@IIPs being transferred to the solid glass fiber paper and improve the portability of the device. Moreover, this platform allows to simultaneous detection of Cu2+ and Hg2+ ions with good selectivity and sensitivity. The proposed method reveals that the copper ion imprinted fluorescent sensor demonstrated a good linearity from 0.11 to 58.0μg/L with the detection limit of 0.035μg/L and the mercury ion linear range is 0.26–34.0μg/L with detection limit of 0.056μg/L. Importantly, this device can provide quantitative information conveniently and show great potential to be further extended to the detection of other metal ions for environmental monitoring and food safety field.
Graphene nanoribbons have attracted attention because of their novel electronic and spin transport properties, and also because nanoribbons less than 10 nm wide have a bandgap that can be used to ...make field-effect transistors. However, producing nanoribbons of very high quality, or in high volumes, remains a challenge. Here, we show that pristine few-layer nanoribbons can be produced by unzipping mildly gas-phase oxidized multiwalled carbon nanotubes using mechanical sonication in an organic solvent. The nanoribbons are of very high quality, with smooth edges (as seen by high-resolution transmission electron microscopy), low ratios of disorder to graphitic Raman bands, and the highest electrical conductance and mobility reported so far (up to 5e(2)/h and 1,500 cm(2) V(-1) s(-1) for ribbons 10-20 nm in width). Furthermore, at low temperatures, the nanoribbons show phase-coherent transport and Fabry-Perot interference, suggesting minimal defects and edge roughness. The yield of nanoribbons is approximately 2% of the starting raw nanotube soot material, significantly higher than previous methods capable of producing high-quality narrow nanoribbons. The relatively high-yield synthesis of pristine graphene nanoribbons will make these materials easily accessible for a wide range of fundamental and practical applications.
Graphene nanoribbons (GNRs) are materials with properties distinct from those of other carbon allotropes. The all-semiconducting nature of sub-10-nm GNRs could bypass the problem of the extreme ...chirality dependence of the metal or semiconductor nature of carbon nanotubes (CNTs) in future electronics. Currently, making GNRs using lithographic, chemical or sonochemical methods is challenging. It is difficult to obtain GNRs with smooth edges and controllable widths at high yields. Here we show an approach to making GNRs by unzipping multiwalled carbon nanotubes by plasma etching of nanotubes partly embedded in a polymer film. The GNRs have smooth edges and a narrow width distribution (10-20 nm). Raman spectroscopy and electrical transport measurements reveal the high quality of the GNRs. Unzipping CNTs with well-defined structures in an array will allow the production of GNRs with controlled widths, edge structures, placement and alignment in a scalable fashion for device integration.
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