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Purpose: PI3K and STAT3 are frequently activated in cancer progression. However, little is known about the underlying mechanisms by which PI3K and STAT3 regulate head and neck squamous cell cancer (HNSCC) growth. The lncRNA HOX transcript antisense RNA (HOTAIR) was found to modulate the progression of HNSCC. In this study, we attempted to establish the correlation of PI3K/STAT3/HOTAIR signaling with the progression of HNSCC and its sensitivity toward platinum-based and targeted anti-EGFR combination therapy.Experimental Design: We first analyzed the STAT3/HOTAIR and PI3K/AKT level in human HNSCC samples. We then activated or suppressed STAT3/HOTAIR and determined the effects on HNSCC cell proliferation in vitro and the growth of UM1 xenograft tumor, an orthotopic model of HNSCC. The sensitivity of HNSCC cells toward cisplatin and cetuximab was determined by in vitro assays.Results: HNSCC samples showed significantly robust expression/activation of STAT3, HOTAIR, PI3K, and AKT, compared with normal squamous epithelium. STAT3 inhibition with WP1066 decreased HOTAIR level and sensitized HNSCC to cisplatin or cetuximab. STAT3 promoted HOTAIR transcription and its interaction with pEZH2-S21, resulting in enhanced growth of HNSCC cells. In addition, overexpression of HOTAIR promoted the growth of UM1 xenograft tumors in vivo.Conclusions: Our results suggest that STAT3 signaling promotes HNSCC progression via regulating HOTAIR and pEZH2-S21 in HNSCC with PI3K overexpression/activation. These findings provide a rationale to target the STAT3/HOTAIR/pEZH2-S21 regulatory axis for treating patients with HNSCC. Clin Cancer Res; 24(11); 2665–77. ©2018 AACR.

Strong metal-support interactions characteristic of the encapsulation of metal particles by oxide overlayers have been widely observed on large metal nanoparticles, but scarcely occur on small nanoclusters (2 nm) for which the metal-support interactions remain elusive. Herein, we study the structural evolution of Pt nanoclusters (1.5 nm) supported on anatase TiO

Esophageal cancer is one of the most common human malignancies and ranks sixth for global mortality; the major histological type is esophageal squamous cell carcinoma (ESCC). Here we assessed the effect of long non-coding (lnc) RNA OIP5-AS1 on the miR-30a-5p/Forkhead box protein D1 (FOXD1) axis in ESCC and investigated the underlying mechanism involving the ERK1/2 signaling pathway. lnc RNA OIP5-AS1 was highly expressed in human ESCC tissues and cells, targeted miR-30a-5p, and inhibited miR-30a-5p expression. Additionally, in human ESCC tissues, miR-30a-5p was poorly expressed, whereas FOXD1 mRNA and protein were highly expressed, with a negative correlation between miR-30a-5p and FOXD1 expression. miR-30a-5p targeted and inhibited FOXD1 expression. FOXD1 promoted the proliferation and invasion of ESCC and was related to the ERK1/2 signaling pathway; ERK1/2 inhibitors (LY-3214996) reversed the biological function of FOXD1. miR-30a-5p combined with FOXD1 regulated ERK1/2 expression and inhibited tumor growth in vivo. In this study, micro- and nano-particles were used as carriers to construct Nanocapsules carrying miR-30a-5p mimics and miR-30a-5p inhibitor through self-assembly method, so as to realize an efficient Nanocapsules delivery system of miR-30a-5p to esophageal cancer cells. It provides insights into targeted drug therapy and the development of micro- and nano-particles carriers.

Despite acknowledgment of structural reconstruction of materials following oxygen evolution reaction (OER) reaction, the role of support during the reconstruction process has been ignored. Given this, we directly in situ transform the residual iron present in raw single-walled carbon nanotubes (SWCNT) into Fe2O3 and thus build Fe2O3-CNT as the model system. Intriguingly, an anomalous self-optimization occurred on SWCNT and the derived components show satisfactory electrochemical performance. Soft X-ray absorption spectroscopy (sXAS) analysis and theory calculation correspondingly indicate that self-optimization yields stronger interaction between SWCNT and Fe2O3 nanoparticles, where the electrons migrate from Fe2O3 to optimized SWCNT. Such polarization will generate a positive charge center and thus boost the OER activity. This finding directly observes the self-optimization of support effect, providing a new perspective for OER and related electrochemical reactions.

The ambiguous mechanism of electrocatalysts for the oxygen evolution reaction (OER) greatly hinders their industrial applications toward renewable and clean energy conversion. Here, we elaborately prepared a cobalt sulfide catalyst to perform a comprehensive study of the OER performance under neutral/alkaline conditions. The combination of synchrotron-based operando X-ray spectroscopic investigations and electron microscopy observations captured a chameleon-like structural self-optimization on the cobalt sulfide oxygen evolution electrocatalyst in both neutral and alkaline electrolytes. Driven by the actual working conditions (pH gradient, electrical potential, etc.), distinct catalytic sites could be activated dramatically. In particular, the CoOOH supported on a single-walled carbon nanotube (CoOOH-SWCNT) with residual S species was identified as the true catalyst under alkaline conditions rather than the entirely transformed CoOOH-SWCNT, while the oxygenated CoS-SWCNT (O-CoS-SWCNT) was formed as the true catalyst under neutral conditions. Undoubtedly, such a mechanism of opening different locks with different keys and its microstructural advantages together guarantee the high catalytic activity in different electrolytes. This work provides a promising catalyst as well as sheds light on the very essence of the structural self-optimization process of catalysts. It makes a significant contribution to the advancement of OER relevant studies in the future while providing new ideas for the fields of chemistry and catalysis.

Revealing the substrate–molecule vibronic coupling enhancement, especially the photoinduced charge transfer (CT) process, is hugely important for understanding the surface-enhanced Raman spectroscopy (SERS) enhancement mechanism. In this work, oxygen atoms were extracted from anatase phase TiO2 nanosheets to form oxygen vacancies, and then Au nanoparticles were deposited on defect TiO2 nanosheets. Through this approach, the Raman scattering intensity of methylene blue (MB) had a remarkable enhancement with an enhancement factor (EF) of 1.7 × 108 at the 1621 cm−1 peak. The defect level located below the conduction band (CB) of anatase calculated by means of density functional theory (DFT) and the Fermi level of gold both generated new photoinduced charge transfer channels from metal through molecule to semiconductor when the incident laser energy was higher than the energy gap barriers. The CT contribution to the SERS enhancement using a parameter ρCT was calculated quantitatively, which showed that the CT process played a more important role in our system compared with the electromagnetic mechanism (EM). The charge transfer degrees of TiO2, defective TiO2 with oxygen vacancies and defective TiO2 deposited with gold nanoparticles decrease with increasing Raman enhancement (10−4 M MB), which confirm that the increase in the transition routes of the CT process was also responsible for the Raman scattering enhancement. The metal oxygen semiconductor intelligently adjusted by artificial control of the surface offer a simple and effective way to gain high EFs, which can expend the application of semiconductor SERS substrates.

Ischemia-reperfusion injury (IRI), which involves severe inflammation and edema, is an inevitable feature of the lung transplantation process and leads to primary graft dysfunction (PGD). The activation of aquaporin 1 (AQP1) modulates fluid transport in the alveolar space. The current study investigated the role of AQP1 in ischemia-reperfusion (IR)-induced lung injury.A mouse model of lung IR was established by clamping the left lung hilar for 1 h and released for reperfusion for 24 h. The AQP1 inhibitor acetazolamide (AZA) was administered 3 days before lung ischemia with a dose of 100 mg/kg per day via gavage. Lung injury was evaluated using the ratio of wet-to-dry weight, peripheral bronchial epithelial thickness, degree of angioedema, acute lung injury score, neutrophil infiltration, and cytokine concentrations in bronchoalveolar lavage fluid.Compared with sham treatment, ischemia with no reperfusion (IR 0h) and ischemia with reperfusion for 24 h (IR 24 h) significantly upregulated AQP1 expression, increased the wet/dry weight ratio, angioedema, neutrophil infiltration and cytokine production (interleukin -6 and tumor necrosis factor -α) and thickened the peripheral bronchial epithelium. AZA exacerbated inflammation and pulmonary edema.AQP1 may exert a protective effect against IR-induced lung injury, which could be attributed to alleviating pulmonary edema and inflammation. AQP1 upregulation might be a potential application to alleviate lung IRI and decrease the incidence of PGD.

Small cell lung cancer (SCLC) has a high degree of plasticity and is characterized by a remarkable response to chemotherapy followed by the development of resistance. Here, we use a mouse SCLC model to show that intratumoral heterogeneity of SCLC is progressively established during SCLC tumorigenesis. YAP/TAZ and Notch are required for the generation of non-neuroendocrine (Non-NE) SCLC tumor cells, but not for the initiation of SCLC. YAP signals through Notch-dependent and Notch-independent pathways to promote the fate conversion of SCLC from NE to Non-NE tumor cells by inducing Rest expression. In addition, YAP activation enhances the chemoresistance in NE SCLC tumor cells, while the inactivation of YAP in Non-NE SCLC tumor cells switches cell death induced by chemotherapy drugs from apoptosis to pyroptosis. Our study demonstrates that YAP plays critical roles in the establishment of intratumoral heterogeneity and highlights the potential of targeting YAP for chemoresistant SCLC.

Electrochemical water splitting is a promising strategy to generate highly purified molecular hydrogen (H2) without any pollutants, but several challenges have impeded its large-scale application b...

Rationally designing cheap and efficient electrocatalysts at the atomic level is highly desirable for the hydrogen evolution reaction (HER). Here, we demonstrate a metallic MoS2 electrocatalyst decorated with platinum single atoms. When combined with electron microscopy observations, our synchrotron X-ray characterizations and theoretical calculations clearly reveal that the doped Pt atoms bond to S atoms on the surface of MoS2. Notably, these Pt single atoms serve as critical active centers for the HER through capturing H+ from the solution. The optimized Pt-MoS2 catalysts achieve significantly enhanced HER performance due to the single-atom coordination effect. This finding is expected to facilitate further realization of hybridized catalysts through the monatomic riveting strategy.

Layered transition metal dichalcogenides (TMDs) belong to a versatile family of two-dimensional materials, having exceptional optical, electronic, physical, and chemical properties. In fact, the in...

Dispersing catalytically active metals as single atoms on supports represents the ultimate in metal utilization efficiency and is increasingly being used as a strategy to design hydrogen evolution reaction (HER) electrocatalysts. Although platinum (Pt) is highly active for HER, given its high cost it is desirable to find ways to improve performance further while minimizing the Pt loading. Here, we use onion-like nanospheres of carbon (OLC) to anchor stable atomically dispersed Pt to act as a catalyst (Pt1/OLC) for the HER. In acidic media, the performance of the Pt1/OLC catalyst (0.27 wt% Pt) in terms of a low overpotential (38 mV at 10 mA cm−2) and high turnover frequencies (40.78 H2 s−1 at 100 mV) is better than that of a graphene-supported single-atom catalyst with a similar Pt loading, and comparable to a commercial Pt/C catalyst with 20 wt% Pt. First-principle calculations suggest that a tip-enhanced local electric field at the Pt site on the curved support promotes the reaction kinetics for hydrogen evolution. Isolating metal atoms on supports is becoming an increasingly studied approach to design water splitting electrocatalysts. Here, the authors prepare a hydrogen evolution catalyst comprising atomically dispersed Pt atoms on curved carbon supports, which outperform similar catalysts where the support is flat.

Tungsten Disulfide (WS

Ruthenium (Ru)-based electrocatalysts as platinum (Pt) alternatives in catalyzing hydrogen evolution reaction (HER) are promising. However, achieving efficient reaction processes on Ru catalysts is still a challenge, especially in alkaline media. Here, the well-dispersed Ru nanoparticles with adjacent Ru single atoms on carbon substrate (Ru

Two-dimensional transition metal dichalcogenide (2D TMDs) alloys, consisting of three or more elements, offer a luxury variety of chemical and physical properties through elemental ratio alteration, thus may provide ideal candidate with tunable band gap for specific electrical applications. In this work, we demonstrate a high-quality layered MoSe

Aberrant signal transducer and activator of transcription 3 (STAT3) signaling is a critical factor that drives the invasion and metastasis of head and neck squamous cell carcinoma (HNSCC). However, the underlying mechanisms of STAT3 overexpression and regulation of HNSCC metastasis remain unknown. In the current study, we demonstrated that upregulated TGF-β may promote epithelial-mesenchymal transition (EMT) through STAT3 activation. In addition, we explored the contributions of STAT3 to HNSCC with a specific focus on its transcriptional regulation and its interaction with the long noncoding RNA (lncRNA) metastasis associated lung adenocarcinoma transcript 1 (malat1). Chromatin immunoprecipitation (ChIP) and luciferase reporter assays revealed that STAT3 could bind to the malat1 promoter region and transcriptionally activate malat1 expression; then, malat1 interacted reciprocally with miR-30a, inducing EMT and accelerating HNSCC metastasis. In summary, our discoveries illuminate how aberrant STAT3 activation confers an oncogenic function in HNSCC and therefore may provide a theoretical foundation for STAT3 as a therapeutic target in HNSCC.

Purpose: PI3K and STAT3 are frequently activated in cancer progression. However, little is known about the underlying mechanisms by which PI3K and STAT3 regulate head and neck squamous cell cancer (HNSCC) growth. The lncRNA HOX transcript antisense RNA (HOTAIR) was found to modulate the progression of HNSCC. In this study, we attempted to establish the correlation of PI3K/STAT3/HOTAIR signaling with the progression of HNSCC and its sensitivity toward platinum-based and targeted anti-EGFR combination therapy. Experimental Design: We first analyzed the STAT3/HOTAIR and PI3K/AKT level in human HNSCC samples. We then activated or suppressed STAT3/HOTAIR and determined the effects on HNSCC cell proliferation in vitro and the growth of UM1 xenograft tumor, an orthotopic model of HNSCC. The sensitivity of HNSCC cells toward cisplatin and cetuximab was determined by in vitro assays. Results: HNSCC samples showed significantly robust expression/activation of STAT3, HOTAIR, PI3K, and AKT, compared with normal squamous epithelium. STAT3 inhibition with WP1066 decreased HOTAIR level and sensitized HNSCC to cisplatin or cetuximab. STAT3 promoted HOTAIR transcription and its interaction with pEZH2-S21, resulting in enhanced growth of HNSCC cells. In addition, overexpression of HOTAIR promoted the growth of UM1 xenograft tumors in vivo. Conclusions: Our results suggest that STAT3 signaling promotes HNSCC progression via regulating HOTAIR and pEZH2-S21 in HNSCC with PI3K overexpression/activation. These findings provide a rationale to target the STAT3/HOTAIR/pEZH2-S21 regulatory axis for treating patients with HNSCC. Clin Cancer Res; 24(11); 2665–77. ©2018 AACR.

Because the reconstruction of catalysts is generally observed during oxidation reactions, understanding the intrinsic structure-related reconstruction ability of electrocatalysts is highly desirable but challenging. Herein, a controllable hydrolysis strategy is developed to obtain nickel hydroxide electrocatalysts with controllable nickel vacancy (VNi) concentrations, as confirmed by advanced spectroscopic characterization. Electrochemical measurements show that the reconstruction can be promoted with the increase of VNi concentration to generate true active components, thereby boosting activities for both oxygen evolution reaction (OER) and urea oxidation reaction (UOR). Density functional theory calculations confirm that the increased VNi concentration yields decreased formation energies of the true active components during reactions. This work provides fundamental understanding of the reconstruction ability of electrocatalysts in anodic oxidation reactions from the view of intrinsic defects.

Atomic intercalation in two-dimensional (2D) layered materials can be used to engineer the electronic structure at the atomic scale and generate tuneable physical and chemical properties which are quite distinct in comparison with the pristine material. Among them, electron-doped engineering induced by intercalation is an efficient route to modulate electronic states in 2D layers. Herein, we demonstrate a semiconducting to metallic phase transition in zirconium diselenide (ZrSe2) single crystals via controllable incorporation of copper (Cu) atoms. Our angle resolved photoemission spectroscopy (ARPES) measurements and first-principles density functional theory (DFT) calculations clearly revealed the emergence of conduction band dispersion at the M/L point of the Brillouin zone due to Cu-induced electron doping in ZrSe2 interlayers. Moreover, electrical measurements in ZrSe2 revealed semiconducting behavior, while the Cu-intercalated ZrSe2 exhibited a linear current–voltage curve with metallic character. The atomic intercalation approach may have high potential for realizing transparent electron-doping systems for many specific 2D-based nanoelectronic applications.

Atomically dispersed catalysts have attracted attention in energy conversion applications because their efficiency and chemoselectivity for special catalysis are superior to those of traditional catalysts. However, they have limitations owing to the extremely low metal-loading content on supports, difficulty in the precise control of the metal location and amount as well as low stability at high temperatures. We prepared a highly doped single metal atom hybrid via a single-step thermal pyrolysis of glucose, dicyandiamide, and inorganic metal salts. High-angle annular dark field-scanning transmission electron microscopy (HAADF-STEM) and X-ray absorption fine structure spectroscopy (XAFS) revealed that nitrogen atoms doped into the graphene matrix were pivotal for metal atom stabilization by generating a metal-Nx coordination structure. Due to the strong anchoring effect of the graphene matrix, the metal loading content was over 4 wt.% in the isolated atomic hybrid (the Pt content was as high as 9.26 wt.% in the Pt-doped hybrid). Furthermore, the single iron-doped hybrid (Fe@N-doped graphene) showed a remarkable electrocatalytic performance for the oxygen reduction reaction. The peak power density was ∼199 mW·cm−2 at a current density of 310 mA·cm−2 and superior to that of a commercial Pt/C catalyst when it was used as a cathode catalyst in assembled zinc-air batteries. This work offered a feasible approach to design and fabricate highly doped single metal atoms (SMAs) catalysts for potential energy applications.

Hierarchical microstructures assembled with nanostructures can effectively enhance the electrochemical performances of electrode materials for rechargeable Li/Na-ion batteries. Due to the large ionic radius of sodium, this kind of design and synthesis is more important for Na-battery cathodes, which represent a cost-effective alternative for energy storage applications. Here ball-in-ball hierarchical microspheres assembled with micron shaped flakes of the P2-type Na0.7Ni0.18Mn0.64Co0.18O2 have been designed and synthesized via hydrothermal reaction followed by stepwise calcination process. As a cathode material of the Na-ion battery, this novel and uniform hierarchical structure exhibits very high specific capacity and superior rate performance with discharge capacities of 208 mAh g−1 at 0.05 C and 46 mAh g−1 at 10 C, and an excellent cycling stability with about 78% capacity retention at 1 C after 50 cycles. These performances are better than any layered oxide cathode material for reversible Na-ion batteries reported in the literature, prepared via the conventional solid-state method. Combining ex-situ x-ray absorption spectroscopy characterization, x-ray diffraction, field emission scanning electron microscopy, scanning transmission electron microscopy and electrochemical characterization, we demonstrate that the superior performances can be attributed to the unique ball-in-ball hierarchical structure assembled with micron shaped flakes. This configuration could effectively reduce the path of Na ion diffusion, increases the contact area between electrodes and electrolyte and buffers the volume changes during the Na ion insertion/extraction processes.

The integration of active components and conductive supports forming free-standing electrodes is highly desirable for a series of energy storage and conversion devices. Herein, a facile hydrothermal method is developed to achieve the coupling of NiFe layered double hydroxide (LDH) and single-walled carbon nanotubes (SWNT) film, forming an integrated flexible electrode for oxygen evolution reaction (OER). The electrode requires a low overpotential of 250 mV to reach a current density of 10 mA cm–2 in 1 M KOH, and shows rapid reaction kinetics with a Tafel slope of 35 mV dec–1. Advanced soft X-ray absorption near-edge structure measurements efficiently indicate strong interfacial electron coupling between the LDH and SWNT, which authentically contributes to superior OER performance. This work provides a new strategy to design binder-free and flexile electrodes for practical application.

In most cases, layered transition metal dichalcogenides (LTMDs), containing metallic phases, show electrochemical behavior different from their semiconductor counterparts. Typically, two-dimensional layered metallic 1T-MoS2 demonstrates better electrocatalytic performance for water splitting compared to its 2H counterpart. However, the characteristics of low metallic phase concentration and poor stability limit its applications in some cases. Herein, we demonstrate a simple and efficient bottom-up wet-chemistry strategy for the large-scale synthesis of nanoscopic ultrathin Mo1–xWxS2 nanosheets with enlarged interlayer spacing and high metallic phase concentration. Our characterizations, including X-ray absorption fine structure spectroscopy (XAFS), high-angle annular dark-fieldscanning transmission electron microscopy (HAADF-STEM), and X-ray photoelectron spectroscopy (XPS) revealed that the metallic ultrathin ternary Mo1–xWxS2 nanosheets exhibited distorted metal–metal bonds and a tunable metallic phase concentration. As a proof of concept, this optimized catalyst, with the highest metallic phase concentration (greater than 90%), achieved a low overpotential of about–155 mV at a current density of –10 mA/cm2, a small Tafel slope of 67 mV/dec, and an increased turnover frequency (TOF) of 1.3 H2 per second at an overpotential of –300 mV (vs. reversible hydrogen electrode (RHE)), highlighting the importance of the metallic phase. More importantly, this study can lead to a facile solvothermal route to prepare stable and high-metallicphase-concentration transition-metal-based two-dimensional materials for future applications.

Rational design of bifunctional oxygen electrocatalysts with high activity and low cost is crucial but still challenging for the development of rechargeable energy storage devices. In this work, a novel bimetallic phosphide confined within P, N co-doped carbon layers is achieved through a space-confinement phosphorization strategy. Electrochemical measurements demonstrate that the obtained bimetallic phosphide nanoparticle-containing hybrid can serve as a highly efficient bifunctional oxygen reduction and evolution reaction (ORR/OER) catalyst. It delivers a small potential difference of 0.75 V in 0.1 M KOH solution along with long-term catalytic durability, superior to most of the non-precious metal catalysts reported to date. The detailed synchrotron-based spectra results combined with structural characterizations reveal that the constructed hierarchical structure endows the confined bimetallic phosphide catalyst with abundant catalytic sites and stable spatial structure, thereby achieving remarkable electrocatalytic performance. This work opens up a facile way to design effective and durable bifunctional oxygen electrocatalysts for practical applications in renewable energy production, especially in rechargeable metal–air batteries and regenerative fuel cells.

The oxygen evolution reaction (OER) involving multi-step electron transfer is a challenging approach for water-splitting due to its sluggish kinetics. It is desirable to explore more efficient electro-catalysts with earth-abundant elements. Herein, we employed a high-temperature polymerization method to develop a structure consisting of graphitic carbon nitride (g-C3N4) nanopatch enveloped carbon nanotubes (CNTs), where isolated Ni and Fe atoms were embedded into the tri-s-triazine units of g-C3N4 by forming a metal–Nx structure. The designed dual-metal catalyst exhibited remarkable OER performance with an extremely low overpotential (∼326 mV at 10 mA cm−2) and a small Tafel slope (67 mV per decade), which is superior to those of state-of-the-art electrocatalysts with metal–Nx coordination and the benchmark IrO2/C catalyst. In combination with atomic microscopy observations, our synchrotron-based X-ray absorption spectroscopy results revealed that, as compared to single-metal (Fe or Ni) doped hybrids, the electronic structures of both Ni and Fe atoms were reconfigured in the obtained dual-metal samples. Notably, increase of the oxidative state in Ni sites after multi-metal doping directly contributed to more active sites and favored the OER process, assisted by the porous structure and good electrical contacts between CNTs and g-C3N4. This investigation clearly demonstrated a unique synergistic effect in atomically dual-metal doped catalysts, thus it may provide a versatile route to regulate the electronic structures of single atomic catalysts through engineering of neighboring elements and coordination number.

Few-layer ternary FePS3 nanosheets, prepared via chemical vapor transport synthesis and ball-milling exfoliation, exhibit excellent electrocatalytic performance for the oxygen evolution reaction in an alkaline medium. Combined with first principles calculations, our X-ray spectroscopy and HRTEM results clearly reveal that the introduction of in-plane defects in FePS3 layers after exfoliation and formation of a FePS3-FeOOH heterostructure during the OER process largely contribute to the catalytic activity enhancement.

We present high quality WX2 (X = S, Se) single crystals synthesized via an improved chemical vapor transport technique. Morphological and structural characteristics of the as-grown layered single crystals were analyzed using SEM, TEM, XPS, Raman spectroscopy, XRD and UV visible spectroscopy characterization techniques. Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and charge-discharge analysis reveal the insights for WX2 single crystals to be used an as excellent material for electrochemical supercapacitors. Notably the obtained supercapacitor electrodes show excellent cycle stability and high capacitance retention of 80 and 99% for WS2 and WSe2 respectively after 20,000 cycles, suggesting their high potential in electrochemical energy storage applications.

Developing flexible electrode is essential for new generation wearable electronics and energy devices. Combining with membrane-assisted vacuum filtration, highly flexible and stable hybridized electrodes, containing of S-doped graphene, carbon nano-onion (OLC) and Ni3S2 composite (GCNi3S2) are obtained. X-ray absorption characterizations reveal the transfer of electrons from C to Ni atoms due to the tight interface between Ni3S2 and GO/OLC, indicating the synergistic effect on fast redox reaction and ultrashort ion diffusion pathway among the hybrid electrodes. The assembled flexible symmetrical all-solid-state supercapacitor exhibits high volumetric capacitance of 55.3 F cm−3, along with an outstanding energy density of 3.63 Wh cm−3 and excellent stability of 5000 cycles with 97.2% capacitance remaining. The bending tests further confirm outstanding flexible performance in the capacitor device. Moreover, the assembled micro supercapacitor with GCNi3S2 electrode indicates the advantage of this membrane-assisted assembled strategy for easily realizing various flexible films as multitype supercapacitor's electrode which is otherwise difficult for powder-like materials.

Tungsten Disulfide (WS2) films, as one of the most attractive members in the family of transition metal dichalcogenides, were synthesized typically on SiO2/Si sub-strate by confine-spaced chemical vapor deposition (CVD) method. The whole pro-cess could be controlled efficiently by precursor concentration and fast thermal pro-cess. To be priority, the effect of fast heating-up to cooling-down process and source ratio-dependent rule for WS2 structure have been systematically studied, leading to high-yield and fine structure of monolayer WS2 films with standard triangular mor-phology and average edge length of 92.4 μm. The growth time of the samples was regulated within 3 minutes, and the optimal source ratio of sulfur to tungsten oxide is about 200:3. The whole experimental duration was about 50 minutes, which is only about quarter in comparison to relevant reports. We assume one type of "multi-nucleation dynamic process" to provide a potential way for fast synthesis of the sam-ples. Finally, the good performance of as-fabricated field-effect transistor (FET) on WS2 film was achieved, which exhibits high electron mobility of 4.62 cm2V−1s−1, fast response rate of 42 ms, and remarkable photoresponsivity of 3.7×10-3A/W. Our work will provide a promising robust way for rapid synthesis of high-quality monolayer TMDs films and pave the way for the potential applications of TMDCs.

LiMn2O4 (LMO) spinel cathode materials are modified with MoO3 coating synthesized using a simple wet chemical method. The surface modified samples show much better capacity retention than pristine LMO. In specially, 3 wt% MoO3 coated sample (LMO/M3) exhibit superior rate specific capacity with 110, 90 and 75 mAhg−1 at 5, 7 and 10 C, respectively. In addition, after 900 cycles at a current of 2 C, a capacity retention of 69.1% was achieved for LMO/M3, which is higher than the 39.6% for the pristine LMO. The enhancements of the electrochemical performance can be largely attributed to the stabilization of the cathode structure by suppressing the manganese dissolution in the electrolyte and in favor for Li+ ion diffusion after MoO3 coating.

Rational design and facet-engineering of nanocrystal is an effective strategy to optimize the catalytic performance of abundant and economic semiconductor-based photocatalysts. In this study, we demonstrate a novel ternary Cu2MoS4 nanotube with the {010} facet exposed, synthesized via a hydrothermal method. Compared with two-dimensional Cu2MoS4 nanosheet with the {001} facet exposed, this one-dimensional nanotube exhibits highly enhanced performance of photodegradation and water splitting. Both theoretical calculations and experimental results suggest that the conduction band minimum (CBM) of the {010} facet crystal shows lower potential than that of the {001} facet. In particular, the up-shifted CBM in Cu2MoS4 nanotube is significantly beneficial for the absorption of dye molecules and reduction of H+ to H2. These results may open a new route for realizing high-efficiency photocatalysts based on Cu2MX4 by facet engineering.

Two-dimensional stable metallic 1T-MoSe2 with expanded interlayer spacing of 10.0 A in situ grown on SWCNTs film is fabricated via a one-step solvothermal method. Combined with X-ray absorption near-edge structures, our characterization reveals that such 1T-MoSe2 and single-walled carbon nanotubes (abbreviated as 1T-MoSe2/SWCNTs) hybridized structure can provide strong electrical and chemical coupling between 1T-MoSe2 nanosheets and SWCNT film in a form of C–O–Mo bonding, which significantly benefits a high-efficiency electron/ion transport pathway and structural stability, thus directly enabling high-performance lithium storage properties. In particular, as a flexible and binder-free Li-ion anode, the 1T-MoSe2/SWCNTs electrode exhibits excellent rate capacity, which delivers a capacity of 630 mAh/g at 3000 mA/g. Meanwhile, the strong C–O–Mo bonding of 1T-MoSe2/SWCNTs accommodates volume alteration during the repeated charge/discharge process, which gives rise to 89% capacity retention and a capacity of 9...

Spinel LiNi 0.5 Mn 1.5 O 4 (LNMO) is one of the most promising high voltage cathode materials for future application. Herein, we report a simple method to prepare nanoscale TiO 2 -coated LNMO composites (LNMO-T). The thin TiO 2 coating layer was pasted on the surface of host material, which favors Li + ions diffusions. Compared to the bare LNMO, the surface modified composites LNMO-T shows outstanding rate capability and excellent cycling ability. In particularly, a discharge capacity of 74.5 mAh/g can be still delivered at 15 C and about 88.5% capacity retention at 2 C after 500 cycles. These results suggest that the TiO 2 coating can not only suppress the dissolution of manganese in the electrolyte but also enhance the conductivity of cathode. This study demonstrates that the potential of developing high energy density cathode materials by surface modification with TiO 2 membrane at nanoscale for future applications.

Layered Cu2MoS4, consisting of earth-abundant elements, is regarded as a potential catalyst for the hydrogen evolution reaction (HER). Herein, we demonstrate a Cu2O-based template strategy to synthesise hierarchical hollow nanostructures of Cu2MoS4. The characterizations reveal that the electrochemically active surface of the hollow Cu2MoS4 is largely enhanced, in contrast to the nanosheet or nanoparticle structures. As the direct outcome, the designed hierarchical hollow structures display excellent HER activities with a low overvoltage and small Tafel slope. This study may provide new inspiration for the research of other ternary sulphide materials as well as subsequently accelerating their applications in the field of catalysis.

Layered transition metal disulfides are currently being widely studied for advanced energy generation and storage applications. Here we report a facile template-assisted solvothermal strategy to obtain a hierarchical nanotubular structure consisting of ultrathin MoS2 nanosheets with a metallic 1T phase. Synchrotron radiation based X-ray absorption fine structure (XAFS) and X-ray photoelectron spectroscopy (XPS) are used to investigate the structure and electronic properties of the 1T-MoS2, which are largely different from annealed samples. Its hierarchical structure makes the obtained nanotubular 1T-MoS2 an excellent electrode material for supercapacitors, with a high specific capacitance of 328.547 F g−1 at a current density of 1 A g−1 and 243.66 F g−1 at a current density of 15 A g−1. Moreover, the material displays excellent capacitance retention, retaining 98.4% capacity after 5000 cycles at a current density of 3 A g−1. Notably, a high specific capacitance of 250 F g−1 at 1 A g−1 is also achieved in a two-electrode symmetrical cell, suggesting its great potential for new-generation supercapacitors.