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Conventional single thermal nature of phase change materials (PCMs) seriously obstructs their frontier applications. Herein, we designed advanced carbon nanotube (CNT) bundles assembled flexible hierarchical framework based phase change material composites for high-performance thermotherapy of allergic rhinitis. Hierarchically interconnected 3D freestanding flexible CNT sponge was constructed via a facile organic solvent-free route using table salt as a sacrificial template. The resulting hierarchical CNT sponge serves as an ideal compatible supporting host and polyethylene glycol (PEG) serves as an excellent thermal energy guest. Subsequently, we designed advanced portable integrated functional mask consisting of outer air purification layer and inner thermal regulation layer for the thermotherapy of allergic rhinitis, in which pristine CNT sponge serves as an excellent particulate matter capturer and PEG-infiltrated CNT sponge serves as a superior thermal regulator. Strikingly, our uniquely constructed flexible CNT sponge-involved composite PCMs assisted by polyvinylidene fluoride (PVDF) harvest high-performance thermotherapy (~33 ​min of the plateau at ~43.5 ​°C). The corresponding medical results (HE staining and Wrights staining) further indicate that our designed thermotherapy mask can significantly reduce the inflammatory injury of nasal mucosa. Additionally, pristine hierarchical CNT sponge guarantees the inhaled air quality and enhances the thermotherapy effect. This synthetic strategy can be scaled up for large-scale production. This novel functional host-guest strategy creates an innovative platform for developing advanced multifunctional PCMs with multiple fascinating peculiarities and desired functional properties and teaches an old dog new tricks.

Owing to the high abundance, good conductivity and excellent tolerance to harsh environment, carbon host materials have recently attracted considerable research interest in the fields of electrochemical hydrogen evolution reaction (HER). However, the deficiency of intrinsic active sites within the carbon host materials substantially gives rise to an inferior HER performance. In this work, atomically dispersed ruthenium active sites are deliberately introduced into the carbon host structure by controlled pyrolysis of Ru-doped ZIF-8. With atomic Ru sites on a unique whisker-like secondary microstructure and a favorable porous texture, the optimal product exhibits a high intrinsic activity as well as robust durability, which especially outperforms the Pt/C benchmarking in alkaline media. A combination of control experiments and theoretical calculations demonstrates that atomically dispersed Ru sites within the carbon host matrix serve as the dominant catalytically active sites, and remarkably optimize the free energy of water molecule dissociation during the Volmer step, thus boosting the HER performance.

A novel controlled drug release system based on pH sensitive polyacrylonitrile (PAN) nanoflowers in different kinds of solvents was successfully prepared with azobisisobutyronitrile (AIBN) as the initiator and without any emulsifier or stabilizer by a one step static polymerization method. The composition and structure of the PAN nanoflowers were analyzed by FTIR, XRD, SEM, TEM, and laser particle size analysis. The polymer particles consisted of a number of lamellae, with a sheet thickness of about 10 nm, and were similar to the shape of flowers with a particle diameter of about 350 nm. The mechanism of the polymerization reaction and the formation were studied. Moreover, the effects of monomer ratio, initiator concentration, reaction time, dispersion medium and co-monomer on the morphology and particle size of the nanoflowers were also discussed. A relatively large specific surface area was formed during the formation of the nanoflowers, which favored drug adsorption. The results of the in vitro experiments revealed that PAN(TBP) nanoflowers, containing BSA in buffer solution of pH 7.4, demonstrated good sustained-release and the cumulative release rate was about 83% after 260 h. The results also showed that the sustained-release from the PAN(TBP) nanoflowers best fitted the Riger-Peppas model. This study indicated that PAN(TBP) nanoflowers provided a theoretical base for the development of carriers for sustainable drug-release.

A Sisal-Like TiO2/Graphene-Like Carbon Sheets (SL-TiO2/GLCSs) composite was fabricated via a facile one-pot self-assembling route at a two-phase interface. The ingenious P123 was introduced to serve a dual function of carbon precursor and structure-directing agent, which first assembled at the water/oil interfaces and subsequently was in situ carbonized to GLCSs. Then the sisal-like TiO2 grew gradually on the GLCSs along the preferred direction. This process shows several advantages such as simple processes, mild condition, low cost and good combination of SL-TiO2 and GLCSs. The combination of SL-TiO2 with GLCSs significantly helps the adsorption of substrates as well as promotes electron-hole pair separation, exhibiting good photocatalytic activity towards degradation of methylene blue (MB) compared to the pristine SL-TiO2 and commercial P25. This strategy opens up new perspectives for fabricating novel composites of nanooxides/GLCSs.

In this work, a core-shell structured upconversion nanoparticles@zeolitic imidazolate frameworks (ZIF-8) fluorescent nanoprobe (NaErF4:Tm@SiO2@ZIF-8) has been designed for the detection of gallic acid (GA). The mechanism is according to the 3, 3′, 5, 5′-tetramethylbenzidine (TMB) can be oxidized to oxidized TMB (oxTMB) by Ag+. Under 980 nm laser excitation, NaErF4:Tm@SiO2@ZIF-8 can emit red light at 652 nm, which have a good overlap with the absorption spectra of oxTMB, resulting in the fluorescence quenching at 652 nm. Continually adding GA into the above solution, oxTMB will restore to TMB, and the fluorescence intensity at 652 nm gradually recovers, which can realize the detection towards GA. The linear detection range of GA is from 0 to 30 μM, and the limit of detection (LOD) of GA is 0.35 μM. The ZIF-8 can largely enhance the sensitivity of the nanoprobe, due to the physical absorption and the electrostatic attraction between ZIF-8 and the oxTMB. More importantly, this is the first time to realize the detection of GA with high sensitivity by using upconversion fluorescence. Besides, we have realized the analysis of GA in real samples, which certify the feasible of the nanoprobe in potential applications.

Incorporating elemental selenium into parts of the micropores of a high surface area carbonaceous framework can simultaneously buffer volume variation and improve electronic conductivity of the resulting selenium/carbon composite for high-performance lithium-selenium (Li-Se) battery cathodes. In this paper, chitosan-derived porous carbon (CPC) framework has been constructed through a one-step carbonization/activation route, possessing oxygen- and nitrogen-containing functional groups and acquiring a high specific surface area of 2098.6 m2 g−1, a total pore volume of 1.04 cm3 g−1 and a micropore volume of 0.62 cm3 g−1. As a Li-Se battery cathode, at 0.1 C (1 C = 675 mA g−1) the composite cathode of Se-50.2/CPC (Se ∼ 50.2 wt%) delivers the ultrahigh discharge capacities of 801.2, 673.1 and 633.9 mAh g−1 in the 1st, 2nd and 100th cycles, respectively. The change of Se-loading amount proves the volume-buffering positive effect of residual voids on the cycling stability of Se-50.2/CPC composite cathode, and the galvanostatic cycling-dependent decrease of charge-transfer resistance interprets its high-capacity feature and good rate capability. In a word, a facile, low-cost and value-added transformation of chitosan into porous carbon framework may satisfy its potential application in Li-Se batteries.

In order to create realistic loop primitives suitable for the faster CAD of the flat-knitted fabric, we have performed research on the model of the loop as well as the variation of the loop surface. This paper proposes an interlacing point-based model for the loop center curve, and uses the cubic Bezier curve to fit the central curve of the regular loop, elongated loop, transfer loop, and irregular deformed loop. In this way, a general model for the central curve of the deformed loop is obtained. The obtained model is then utilized to perform texture mapping, texture interpolation, and brightness processing, simulating a clearly structured and lifelike deformed loop. The computer program LOOP is developed by using the algorithm. The deformed loop is simulated with different yarns, and the deformed loop is applied to design of a cable stitch, demonstrating feasibility of the proposed algorithm. This paper provides a loop primitive simulation method characterized by lifelikeness, yarn material variability, and deformation flexibility, and facilitates the loop-based fast computer-aided design (CAD) of the knitted fabric.

As one of the most abundant natural aromatic polymers with plentiful oxygen-containing groups in molecular backbones, commercial lignin can be regarded as a sustainable precursor to develop porous carbonaceous frameworks for the encapsulation of elemental selenium. In this paper, an initial combined carbonization/activation of commercial alkaline lignin and subsequent selenium-loading are adopted to fabricate serial composites of lignin-derived porous carbon (LPC) and elemental selenium (i.e., serial Se/LPC composites) for high-performance lithium-selenium (Li-Se) batteries. The high specific surface area, large pore volume and good electron conductivity of each LPC scaffold facilitate the reversible electrochemical reaction of selenium towards metallic Li, and at 0.5 C a Se/LPC composite electrode exhibits a reversible capacity of 596.4 mAh g −1 in the 2nd cycle and a capacity retention of 453.1 mAh g −1 over 300 cycles with an average decay of 0.08% per cycle. The facilely obtained microporous features of LPC scaffold, as well as the high-rate performance of corresponding Se/LPC composites (e.g., 363.2 mAh g −1 , 4 C), indicate that large-scale treatment of the biomass feedstock may find its potential application in renewable green energy sources.

Hierarchical α-Ni(OH)2 assembled of ultrathin nanosheets with the intercalation of diatomic alcohol molecules were synthesized via a facile one-step solvothermal process. The assembly structure avoided the agglomeration of ultrathin nanosheets while retaining their atomic-scale thickness and high surface area. The intercalation of the diatomic alcohol molecules into the transition-metal layers provided larger interlayer spacing and more exposed active sites, which guaranteed the high activity of the α-Ni(OH)2. The as-obtained hierarchical α-Ni(OH)2 exhibited excellent catalytic performance in the reduction of p-nitrophenol, with a maximum reaction rate constant (k) of 6.23 × 10–3 s–1 and a super high activity factor K (K = k/m) of 216.69 s–1 g–1. The layer spacing played the most important role in the reaction, and the catalytic efficiency increased greatly with the increase of the layer spacing of the α-Ni(OH)2. This design concept and synthetic method can also be extended to the production of a wide var...

This paper presents a detailed study of turn-on uniformity under electrostatic discharge events in single-finger and multi-finger traditional DDSCR devices. Since the structure of the multi-finger DDSCR device is not completely symmetrical, the electric field strength of each finger breakdown junction is different, resulting in different impact ionization rates. Therefore, each finger of device cannot be turned on at the same time, and the turned-on finger enters the snap back region and pull down the voltage of the device. If the ESD failure voltage Vt2 of the multi-finger device is less than the trigger voltage Vt1, then other fingers will not turn on until the device fails, and the ESD current can be only discharged through the partial area. The transmission line pulse (TLP) test results show that the failure currents It2 of the single-finger, 2-finger and 4-finger DDSCR devices are 6.22A, 11.83A and 13.33A, respectively, and the 4-finger device cannot be uniformly turned on.

Graphite anode (specific capacity is only 372 mA h g−1) for lithium-ion batteries (LIBs) is not enough for high energy and high power density demands. In this work, MOF-5 was used as a precursor to prepare a porous carbon material embedded with BN (Boron Nitride), while B and N elements will enhance the electron transport speed thus improving the conductivity simultaneously. A large specific surface area of 1790.19 m2 g−1 was provided with this material because of embedding of lamellar BN, therefore it caused excellent cycling stability and high capacity characteristics in LIBs. The capacity retention is 1290 mA h g−1 at 200 mA g−1 and 683 mA h g−1 at 2000 mA g−1. This material provides a solution for improving the performance of LIBs, and it can also be a reference for the development in other fields.

Hybridization of Metal-Organic frameworks (MOFs) with conductive materials has proven to be an efficient way to enhance their oxygen evolution reaction (OER) performance. Here we present a novel primer-induced in situ hybridization method to covalently link the nickel-based two-dimensional (2D) ultrathin MOFs nanosheets and graphene. By considering the energetically favorable anchoring process, thermodynamically prohibited self-polymerization side reaction and high delocalization of lowest unoccupied molecular orbitals (LUMO), the optimal phenylenebisboronic acid (PBA) primer were rapidly identified by screening thousands of primers via a high-throughput periodic density functional theory (DFT) workflow. Aided by the computational results, the PBA molecules were used to be covalently bonded to graphene successfully and then induce the in-situ growth of ultrathin Ni-MOFs nanosheets with terephthalic acid (TPA) as the ligand (denoted as Ni-HMOF@GE-PBA). The as-prepared Ni-HMOF@GE-PBA was demonstrated as a high-performance electrocatalyst for OER, delivering a much lower onset potential than that of simple blending of graphene and Ni-MOFs nanosheets by 150 mV. This design and construction strategy would pave an efficient pathway to rapid exploration and synthesis of new 2D–2D hybrid catalytic materials with excellent performance for OER.

Mesoporous CeO2-based oxides (CuO/CeO2, Fe2O3/CeO2 and La2O3/CeO2) were synthesized by a one-step hydrothermal method. CeO2-based oxides showed the undoped flower-like mesoporous microspheres of 2–6 μm in diameter with high BET surface areas. Copper, iron or lanthanum ions were each successfully doped into ceria and the dopants enhanced the amount of Ce3+ in cerium in all samples, which improved the oxygen mobility and the amount of surface active oxygen. The synthesized CeO2-based oxides showed significantly improved catalytic activity toward the oxidation of styrene, among which CuO/CeO2 exhibited the highest activity of 92.5% conversion. The catalytic activity of the composites was demonstrated to closely parallel their surface area and surface active oxygen atom sites.

Magnetic chitosan microspheres were prepared by the emulsification cross-linking technique in the presence of glutaraldehyde as cross-linking agent, liquid paraffin as dispersant, and Span-80 as emulsifier. The optimal cross-linking time and Co0.5Ni0.5Fe2O4: chitosan ratio were determined. The morphology of particles was studied by different techniques. The adsorption characteristics were studied and the effect exerted by the initial concentration of methyl orange, the time of cross-linking, and the amount of the adsorbent was determined. It is found that the product obtained at the Co0.5Ni0.5Fe2O4: chitosan ratio 1: 4 and the crosslinking time 5 h has the uniform morphology. At room temperature, the Co0.5Ni0.5Fe2O4–chitosan magnetic composite has maximal adsorption for methyl orange at the dosage 20 mg.

Hierarchical nanostructure with hollow feature can greatly promote electrocatalytic activity by facilitating the diffusion of active species and accelerating the contact between catalyst and electrolyte. In this paper, we report the preparation of hierarchical hollow NiFe hydroxide nanospheres assembled from ultrathin nanosheets as the OER electrocatalyst via a simple and gentle self-templating strategy, which includes two steps: the synthesis of Ni(OH)2 nanospheres precursor and its further transformation to the final hollow-spheres after the introduction of Fe3+ via a mild hydrothermal method. The hollow NiFe hydroxide nanospheres were proven to be composed of ultrathin nanosheets which formed porous walls. This unique structure achieved numerous mass transfer channels for electrolytes, ideal pathways for ions and electrons, and a high specific surface area, leading to the improved performance for the product during the electrocatalytic reaction. In addition, the charge transfer rate and structural stability of the architecture have been greatly improved after the addition of Fe3+, which guaranteed high electrochemical performance toward OER. The tafel plot for NiFe-190 without any conductive agents is 60 mV dec−1 and the overpotential needed to reach a current density of 10 mA cm−2 is a 270 mV.

The direct pyrolysis of metal organic frameworks (MOFs) has recently provided an effective method to prepare various metal-incorporated composite carbon materials. In this work, hierarchical Co-embedded N-doped porous carbon microspheres were synthesized by controlled pyrolysis of bimetallic Zn-Co Prussian blue analogues (PBAs), in which the metallic Zn component served as thermally removable template and ligand [Co(CN)6]3− served as both Co and N sources. When devoted to catalyzing the reduction of 4-nitrophenol (4-NPh) into 4-aminophenol (4-APh), the optimized catalyst exhibited a large apparent rate constant of 1.35 min−1 and high turnover frequency (TOF) of 0.0204 s−1, which was superior to the majority of noble-metal-based catalysts. Besides, a home-made continuous flow catalysis system was readily constructed. Control experiments confirmed that both partially uncovered and totally in-built active metallic Co species acted as catalytically active sites. This work might provide a further understanding of the identification of active sites within metal-incorporated carbon-based catalysts.

The dual directional silicon-controlled rectifier (DDSCR) device is widely used in on-chip electrostatic discharge (ESD) protection owing to its bi-directional ESD protection and strong current-tolerating capability per area. In this paper, an asymmetrical dual directional ESD protection device for automotive application was developed in a 0.18-µm Bipolar CMOS DMOS (BCD) technology. In order to verify and predict the proposed ESD protection device’s characteristics, a transmission line pulse (TLP) testing system and a 2-dimension device simulation platform have been used in this work. According to the measurement results, the asymmetrical dual directional silicon-controlled rectifier with a floating P+ region (ADDSCR_FP+) increases the forward holding voltage (Vh) from 3.89 V to 19.7 V and increases the reverse holding voltage from 3.62 V to 19.5 V which only slightly decrease the failure current compared with the traditional asymmetrical dual directional silicon-controlled rectifier (ADDSCR). The ADDSCR_FP+ has the features of symmetrical forward and reverse I-V curves, high holding voltage and high failure current.