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Two-dimensional (2D) borophene has attracted tremendous interest due to its fascinating properties, which have potential applications in catalysts, energy storage devices, and high-speed transistors. In the past few years, borophene was theoretically predicted as an ideal electrode material for lithium-sulfur (Li-S) batteries because of its low-density, metallic conductivity, high Li-ion surface mobility, and strong interface bonding energy to polysulfide. But until now, borophene-based Li-S batteries have not yet been achieved in experiments due to the absence of a large-scale synthetic method of freestanding borophene nanostructures with a high enough structural stability, conductivity, and uniformity. Herein, we developed a low-temperature liquid exfoliation (LTLE) method to synthesize freestanding few-layer β12-borophene single-crystalline sheets with a P6¯m2 symmetry in tens of milligrams. The as-synthesized 2D sheets were used as the polysulfide immobilizers and electrocatalysts of Li-S batteries. The resulting borophene-based Li-S battery delivered an extralarge areal capacity of 5.2 mAh cm-2 at a high sulfur loading of 7.8 mg cm-2, an excellent rate performance of 8 C (@721 mAh g-1), and an ultralow capacity fading rate of 0.039% in 1000 cycles, outperforming commercial Li-ion batteries and many other 2D material-based Li-S batteries. Based on the density functional theory model, the excellent electrochemical performances of the borophene-based Li-S batteries should originate from the enormous enhancement of β12-borophene sheets for both the surface migration of the Li-ions and the adsorption energy of Li2Sn clusters. Our results thus demonstrate a great potential for scalable production of freestanding β12-borophene single-crystalline sheets in future high-performance Li-S batteries.

Two-dimensional (2D) borophene has attracted tremendous interest due to its fascinating properties, which have potential applications in catalysts, energy storage devices, and high-speed transistors. In the past few years, borophene was theoretically predicted as an ideal electrode material for lithium-sulfur (Li-S) batteries because of its low-density, metallic conductivity, high Li-ion surface mobility, and strong interface bonding energy to polysulfide. But until now, borophene-based Li-S batteries have not yet been achieved in experiments due to the absence of a large-scale synthetic method of freestanding borophene nanostructures with a high enough structural stability, conductivity, and uniformity. Herein, we developed a low-temperature liquid exfoliation (LTLE) method to synthesize freestanding few-layer β

Two-dimensional (2D) borophene is predicted as an ideal electrode material for lithium sulfur (Li-S) batteries because of low-density, metallic conductivity, high Li-ion surface mobility and strong interface bonding energy to polysulfide. But until now, 2D borophene-based Li-S batteries have not yet been achieved due to the absence of massive synthesis method. Herein, we developed a novel low-temperature liquid exfoliation (LTLE) method for scalable synthesis of single crystalline 2D few-layer β12-borophene sheets with a \(P\stackrel{-}{6}m2\) symmetry. The as-synthesized 2D sheets were used as the polysulfide immobilizers and electrocatalysts of Li-S batteries for the first time. The resulting Li-S cells employing borophene sheets delivered a strikingly high areal capacity of 5.2 mAh cm− 2 at a high sulfur loading of 7.8 mg cm− 2 with an ultralow capacity fading rate (0.039 % per cycle) in 1000 cycles, outperforming most of the Li-S batteries employing other 2D materials. Under the help of few-layer β12-borophene, their high-activity behaviors should be attributed to the significant enhancement of both the Li-ion’s surface migration and the adsorption energy for Li2Sn clusters based on density functional theory (DFT) models. Our research reveals great potential of 2D β12-borophene sheets in future high-performance Li-S batteries.

Background Aging is one of the dominant factors contributing to erectile dysfunction (ED), and effective treatments for age-associated ED are urgently demanded. In this study, the therapeutic efficiency of bone marrow-derived mesenchymal stem cells (BMSCs) overexpressing microRNA-145 (miR-145) was evaluated in ED. Methods Sixty male Sprague-Dawley rats (24 months old) were randomly divided into 4 treatment groups (n = 15/group): PBS (control), BMSCs, BMSCs transfected with a blank vector (vector-BMSCs), and BMSCs transfected with a lentivirus overexpressing miR-145 (OE-miR-145-BMSCs). Fourteen days after transplantation of BMSCs, erectile function was evaluated by measuring intra-cavernous pressure (ICP) and mean arterial pressure (MAP). Subsequently, penile erectile tissues were harvested and subjected to Masson staining, qRT-PCR, immunofluorescence staining, dual luciferase assay, and Western blot analysis. Results Fourteen days after transplantation, the ICP/MAP was 0.79 ± 0.05 in the OE-miR-145-BMSC group, 0.61 ± 0.06 in the BMSC group, 0.57 ± 0.06 in the vector-BMSC group, and 0.3 ± 0.01 in the PBS group. Treatment with OE-miR-145-BMSCs significantly improved ED (P P P P Conclusions MicroRNA-145 engineered BMSCs effectively attenuate age-related ED. Transplantation of miR-145-overexpressing BMSCs may provide a promising novel avenue for age-associated ED therapy.

Based on the morphology characteristics, low-dimensional (LD) nanostructures with high aspect ratio can be usually divided into nanowire, nanocone, nanotube, nanorod, nanoribbon, nanobelt and so on. Among numerous LD nanostructures, boron-based nanostructures attracted much interest in recent years because they have high melting-point, large electric and thermal conductivity, and low work function. Compared to traditional thermal emission, field emission (FE) has notable advantages, such as lower power dissipation, longer working life, room-temperature operation, higher brightness and faster switching speed. Most studies reveal they have lower turn-on and threshold fields as well as high current density, which are believed as ideal cold cathode nanomaterials. In this review, we will firstly introduce the growth methods of LD boron-based nanostructures (boron monoelement and rare-earth metal hexaboride). Then, we will discuss their FE properties and applications. At last, the conclusions and outlook will be summarized based on the above studies.

Transition metal dichalcogenides (TMDCs) have been intensively researched during the past decade in consequence of their fascinating properties, such as tunable bandgap, high carrier mobility, and extraordinary luminescent efficiency. But compared with their bulk counterparts, atomically thin two-dimensional (2D) TMDCs have an intrinsic lower light absorption (∼5%), preventing them from further applications in optoelectronic area. Commonly, fabrication of high-performance TMDC nanodevices not only requires complicated or expensive process, but also is hard to simultaneously realize significant and uniform enhancement for large-scale planar integrated device applications. Herein, we provided an asymmetric Fabry–Perot (F-P) cavity method to efficiently enhance the light absorption of the monolayer tungsten disulfide (ML WS2). By constructing the F-P cavity structure of WS2/SiO2/Au with an optimal thickness of SiO2 spacer, the visible-light absorptivity of ML WS2 dramatically increased from 5% to 49%. To further testify the enhancement effect of the F-P cavity, this hybrid structure was integrated into photoconductive device and compared with pristine WS2 device. The results showed that the photoresponsivity of the hybrid F-P cavity structure (8.3 A W−1) was found to be 2 orders higher than that of pristine WS2 (0.028 A W−1). Moreover, this hybrid structure exhibited a more remarkable and uniform light-field enhancement than pristine WS2 under 532-nm excitation, attributing to the formation of the constructive interference in F-P resonance cavity. This novel F-P cavity structure can shed new light on substantially and uniformly improving the low absorptivity of 2D nanomaterials for future developments.

It’s not easy to discriminate dried wild-growing Lentinus edodes (WL) and cultivated Lentinus edodes (CL) by conventional method based on the morphological inspection of fruiting bodies. In this paper, fruiting body samples of WL and CL are discriminated by a tri-step IR spectroscopy method, including Fourier transform infrared (FT-IR) spectroscopy, second derivatives infrared (SD-IR) spectroscopy and two-dimensional correlation infrared (2D-IR) spectroscopy under thermal perturbation. The results show that the FT-IR spectra of WL and CL are similar in holistic spectral profile. More significant differences are exhibited in their SD-IR spectra in the range of 1700 - 900 cm -1 . Furthermore, more evident differences have been observed in their synchronous 2D-IR spectra in the range of 2970 - 2900, 1678 - 1390, 1250 -1104 and 1090 - 1030 cm -1 . The CL has thirteen auto-peaks at 2958, 2921, 1649, 1563, 1450, 1218, 1192, 1161, 1140, 1110, 1082, 1065 and 1047 cm -1 , in which the four strongest auto-peaks are at 2921, 1563, 1192 and 1082 cm -1 . The WL shows fifteen auto-peaks at 2960, 2937, 2921, 1650, 1615, 1555, 1458, 1219, 1190, 1138, 1111, 1084, 1068, 1048 and 1033 cm -1 , in which the four strongest auto-peaks are at 2921, 1650, 1190 and 1068 cm -1 . This study shows the potential of FT-IR spectroscopy and 2D correlation analysis in a simple and quick distinction of wild-growing and cultivated mushrooms.

Inorganic boron-based nanostructures have great potential for field emission (FE), flexible displays, superconductors, and energy storage because of their high melting point, low density, extreme hardness, and good chemical stability. Until now, most researchers have been focused on one-dimensional (1D) boron-based nanostructures (rare-earth boride (REB6) nanowires, boron nanowires, and nanotubes). Currently, two-dimensional (2D) borophene attracts most of the attention, due to its unique physical and chemical properties, which make it quite different from its corresponding bulk counterpart. Here, we offer a comprehensive review on the synthesis methods and optoelectronics properties of inorganic boron-based nanostructures, which are mainly concentrated on 1D rare-earth boride nanowires, boron monoelement nanowires, and nanotubes, as well as 2D borophene and borophane. This review paper is organized as follows. In Section I, the synthesis methods of inorganic boron-based nanostructures are systematically introduced. In Section II, we classify their optical and electrical transport properties (field emission, optical absorption, and photoconductive properties). In the last section, we evaluate the optoelectronic behaviors of the known inorganic boron-based nanostructures and propose their future applications.

Being a typical Kondo topological insulator, samarium hexaboride (SmB6) attracts much interest in condensed physics and material sciences in recent years. In comparison with their bulk counterparts, SmB6 nanostructures have more abundant surface electron states due to larger specific surface area, which are believed as idea platforms for studying surface quantum properties and physic mechanism. Through chemical vapor deposition (CVD), SmB6 nanobelt and nanowire films were respectively prepared on Si substrate. Both SmB6 nanowires and nanobelts are proven as the cubic single crystals, and their growth directions are, along [100] and [110], respectively. Field emission (FE) results show that SmB6 nanobelts have a turn-on field of 3.24 V/μm and their maximum current density arrives at 466.16 µA/cm 2, which are better than SmB6 nanowires. Considering that SmB6 nanostructures have lower electron affinity, higher electron conductivity and more abundant surface states, they are regarded as excellent cold cathode nanomaterials if their FE performances can be further improved.