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Despite the development of sterilization, the study of reactive oxygen species (ROS) based disinfection mechanism is still under restrictions due to the lack of direct evidence. In this work, DiI is used to explore the sterilization mechanism in-depth. The mechanism is directly proven to be that the generated ROS would seriously damage the lipid of the cell membrane. It provides direct evidence for the destruction of cell membrane for the first time. These ROS can cause the death of more than 99% of both Gram-negative and Gram-positive bacteria within 120 min under visible light. What's more, MoS

Phosphorus anode is one of the most promising candidates for high-energy-density lithium-ion batteries. Recent studies found the lithiation process of phosphorus is accompanied by the soluble intermediates of lithium polyphosphides. The trans-separator diffusion of polyphosphides is responsible for the capacity decay. Herein, a facile separator modification strategy is proposed for improving the performance of phosphorus anode. The lightweight CNT-modified layer that has a continuous conductive skeleton, a dense structure, and a strong interaction with the soluble lithium polyphosphides can trap, stabilize, and reactivate the active material. Without sophisticated electrode structure design, the cyclability and high-rate performance of the phosphorus anode has been significantly improved, leading to a higher specific capacity of 1505 mAh/g at 250 mA/g (200th cycle) and 1312 mAh/g at 2 A/g. With the advantages of simplicity and low cost, the separator modification strategy provides a new feasible way for further improvement of the phosphorus-based anode.

Zn-Co(OH)2 precursor was hydrothermally deposited on carbon paper at 120°C, using cobalt nitrate and zinc nitrate as raw materials. Then Zn-Co(OH)2 was etched and partially sulfided into CoSOH/Co(OH)2 with 5 mol/L NaOH and 1 mol/L Na2S aqueous solution at room temperature. The catalytic performance in oxygen evolution reaction (OER) was investigated. XRD, SEM, TEM, XPS were used to characterize the microstructure, physical and chemical properties of the catalyst. The results show that the used method can etch Zn atoms, create oxygen vacancies and dope sulfur. The oxygen vacancies and doped sulfur play a positive role in enhancing the OER performance. In addition, amorphous CoSOH also exhibited better OER activity. The synergy between CoSOH and Co(OH)2 finally induces the best catalytic properties (overpotential η=310 mV, Tafel slope b=90 mV/dec) and long-term electrochemical stability, that is CoSOH/Co(OH)2 possess superior electrocatalytic oxygen evolution performance.

With H2WO4 and EDA as precursors, WO3/C intermediate is obtained by mechanical stirring and in-situ solid-phase pyrolysis, then WS2/C composite material is obtained by high temperature vulcanization. The WS2/C composite is characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS) and other instrumental analysis methods. At the same time, the electrocatalytic performance of the catalyst was analyzed by the electrocatalytic steady-state polarization curve (LSV), Tafel slope (Tafel), cycle stability (CP), electrochemical impedance (PEIS) and Electrochemically Active Surface Area (ECSA) tests of the material. The results showed that when the current density of the WS2/C composite is 10 mA/cm2, overpotential is 179 mV, and Tafel slope is 98 mV/dec.

Two-dimensional (2D) material MXenes have been intensively concerned in energy-storage field due to these unique properties of metallic-like conductivity, good hydrophilicity and high volumetric capacity. However, the self-restocking of ultra-thin 2D materials seriously hinders these performances, which significantly inhibits the full exploitation of MXenes in the field of energy storage. To solve this issue, a strategy to prepare delaminated Ti3C2Tx (MXene) nanoflakes/reduced graphene oxide (rGO) composites is proposed using the electrostatic self-assembly between positively charged Ti3C2Tx with tetrabutylammonium ion (TBA+) modification and negatively charged graphene. The nanoflakes of Ti3C2Tx/rGO are well dispersed and arranged in a face-to-face structure to effectively alleviate the self-restacking and provide more electroactive sites for accessible of electrolyte ions. The prepared delaminated Ti3C2Tx/rGO anode shows a high reversible capacity up to 1394 mAh g−1 at a current density of 50 mA g−1. Moreover, a lithium-ion capacitor (LIC) was assembled with delaminated Ti3C2Tx/rGO anode and activated carbon (AC) cathode which can exhibit a specific capacity of 70.7 F g−1 at a current density of 0.1 A g−1 and deliver an ultrahigh energy density of 114 Wh kg−1 at a relatively high power density of 3125 W kg−1. These good electrochemical performances demonstrate the potential of delaminated Ti3C2Tx/rGO as an anode material for lithium-ion capacitors.

Black phosphorus is regarded as a promising anode material due to its high theoretical specific capacity and fast-charging safety compared with the commercial graphite-based anode materials. Howeve...

The separator has an important influence on safety and charge-discharge performances of lithium-ion batteries. In this work, a multilayer composite separator is designed and fabricated by alternate electrospinning of poly (vinyl alcohol) (PVA) nanofibers and electrospraying of ZrO2 nanoparticles. The physical-chemical properties of the separator are systematically investigated. The design of such a layer-by-layer structure not only enhances the electrolyte uptake/retention and thermal resistance but also improves the mechanical strength of the composite separator. In comparison with PE separator and pure PVA electrospun separator, this PVA-ZrO2 composite separator exhibits satisfactory thermal resistance (area shrinkage ratio of 0% at 160 °C), ionic conductivity (2.19 mS/cm), electrolyte wettability (uptake of 350%) and tensile strength (14.5 MPa) as well as better interface compatibility. Moreover, a LiFePO4–Li half-cell with PVA-ZrO2 composite separator displays superior C-rate and cycling performances. It shows a high discharge capacity of 73.0 mA h/g at 16C, which is about 50% of that at 0.2C. The reason for the high capacity retention is the efficient Li+ transmission through the separator, resulting from the well-defined porous structure and the Lewis acid-base interactions of the PVA-ZrO2 composite separator. It can be concluded that this type composite separator with layer-by-layer structure possesses good application prospects for high-performance lithium-ion batteries.

The effective strategy of depositing modified layer on separator is widely utilized to suppress polysulfides shuttle in lithium-sulfur batteries, in which the modified layer partly sacrifices the transport of lithium-ion. Thus far, to simultaneously achieve fast lithium-ion transport and polysulfides-blocking remains a hot yet challenging issue. Herein, we developed a two-dimensional lithiated covalent organic framework nanosheets (Li-CON) layer that possess ordered lithiated-sites in the intrinsic nanopores of Li-CON. Those lithiated-sites can significantly facilitate the lithium-ion transport owing to low diffusion barrier. Besides, the Li-CON promotes Li-S bond breaking of relatively low reactivation energy due to the synergy effect of triazole units and lithiated-sites resulting in fast polysulfides conversion kinetics. Thus, Li-CON modified separator exhibits high lithium-ion conductivity and transference number, meanwhile, suppresses polysulfides shuttle and reduces the charging overpotential contributing to superior long cycle and high rate performance.

FePS3, a classical 2D layered material with transition metal phosphorous trichalcogenides, was investigated as an anode material for Mg ion batteries. We used density functional theory to calculate the Mg storage properties of FePS3, such as Mg adsorption energy, theoretical specific capacity, average voltage, diffusion energy barriers, volume change, and electronic conductivity. The theoretical specific capacity of the FePS3 monolayer is 585.6 mA h/g with a relatively low average voltage of 0.483 V (vs. Mg/Mg2+), which is favorable to a high energy density. The slight change in volume and good electronic conductivity of bulk FePS3 are beneficial to electrode stability during cycling.

Bunches of oriented K2Ti6O13 nanorods coated by a thin carbon layer (4–7 nm) were prepared by combining hydrothermal and heat treatment in sequence. The K2Ti6O13 nanorods possess long- and short-axis crystal orientations of and , respectively, contributing to fast K+ diffusion, and the carbon-coating layer improves the electron conductivity. In addition, the obtained K2Ti6O13/carbon has a high compaction density, which is beneficial for realizing high volumetric specific capacity. When evaluated as a potassium-ion battery anode, the nanorods demonstrated a superior rate capability (122.5, 104.3, 92.3, 78.6 and 65.1 mA h g−1 at current densities of 20, 50, 100, 200 and 500 mA g−1, respectively), a favourable cycle life (118.5 mA h g−1 at 25 mA g−1 for 200 cycles) and high capacity retention.

A tannic-polypyrrole (TA-PPy) coating layer around a phosphorus-nanotube (P-CNT) electrode boosts electronic and ionic transfer, resulting in good high-rate performance and reduced volumetric expansion for lithium-ion batteries.

Zinc metal has a severe dendrite issue caused by the uneven Zn plating/stripping during continual cycles, which hinders the practical application of ZIBs. The surficial atomic structure of zinc anode plays a decisive role in solving dendrites and improving the electrochemical performance. According to the density functional theory results, Zn (100) plane possesses a much stronger adsorption energy of zinc atom compared with the (002), thus zinc atom preferentially nucleates on the (100) surface. It subsequently continues to grow vertically on (100). Herein, the zinc anode is designed with hexagonal-hole patterns (h-Zn) through a phosphoric acid etching reaction. An abundance of Zn (100) crystal planes are exposed perpendicularly to the anode surface, while the (002) surfaces are at the bottom of these hexagonal holes. Zinc prefers to deposit in hexagonal holes at the (100) surfaces, favoring the restraining of the surficial dendrite growth and accelerating the Zn deposition kinetics. Thus, the symmetric cell using h-Zn exhibits a long cycling lifespan for over 1200 h and extremely low polarization voltage of ≈80 mV at 5 mA cm

A new ABW-type luminescent metal–organic framework (MOF) namely (H3O)[Zn2L(H2O)]·3NMP·6H2O (1), constructed with eco-friendly Zn2+ and the multicarboxylate intraligand (LH5) was designed, synthesized and fully characterized by X-ray single-crystal diffraction, steady-state absorption and emission spectroscopy, and SEM observations. The MOF-based suspension sensor 1 (NMP) demonstrated high sensitivity to low-concentration pesticides of chlorothalonil (CTL), nitrofen (NF), trifluralin (TFL), and 2,6-dichloro-4-nitroaniline (DCN), which was assigned to the synergistic effect of the photoinduced electron transfer and the fluorescence resonance energy transfer. With the highest luminescent detection efficiency (KSV up to 11.194 μmol−1 and LOD down to 2.93 ppm) to DCN, 1 (NMP) was successfully applied for the selective sensing of DCN. The MOF-based film sensor 1 (film) illustrated the selective visualization sensing of trace amounts of DCN. In addition, based on the high saturated vapor pressure of TFL and the unique bathochromic shift effect to the emission maxima of 1, the MOF-based luminescent vapor sensing device 1 (LED) successfully exhibited operability for sensing of TFL vapor. The results illustrated a feasible approach to construct new MOF-based luminescent sensors for selective sensing and visualization of pesticides.

Bunches of oriented K2Ti6O13 nanorods coated by a thin carbon layer (4-7 nm) were prepared by combining hydrothermal and heat treatment in sequence. The K2Ti6O13 nanorods possess long- and short-axis crystal orientations of010and001, respectively, contributing to fast K+ diffusion, and the carbon-coating layer improves the electron conductivity. In addition, the obtained K2Ti6O13/carbon has a high compaction density, which is beneficial for realizing high volumetric specific capacity. When evaluated as a potassium-ion battery anode, the nanorods demonstrated a superior rate capability (122.5, 104.3, 92.3, 78.6 and 65.1 mA h g-1 at current densities of 20, 50, 100, 200 and 500 mA g-1, respectively), a favourable cycle life (118.5 mA h g-1 at 25 mA g-1 for 200 cycles) and high capacity retention.

Polymer materials with strong bactericidal properties by impregnating or complexing antibacterial agents were used in daily life. However, based on polymer matrices, the simultaneous acquisition of more environmentally and friendly self-cleaning and sterilization properties may be more beneficial to human health. Herein, a petal-like network photocatalytic β-Bi2O3/Bi2O2.7 heterostructure film with a thickness of ca 0.81 μm was gradually formed layer upon layer on polyvinyl chloride (PVC) polymer matrices through one-step hydrothermal process for the first time, and decorated Ag nanoparticles as co-catalyst. The Ag-decorated β-Bi2O3/Bi2O2.7 heterostructure film showed hydrophobicity, degradation of 97% Rhodamine B (RhB) in 150 min, inactivation of > 99.99% Escherichia coli (E.coli) in 18 h, and E.coli anti-adhesion performance. The photocatalytic properties were mainly ascribed to the generation of ·O2− and h+ due to the synergistic effects of petal-like hierarchical microstructure, good interface quality and accelerated carriers separation among β-Bi2O3, Bi2O2.7 and Ag particles. Furthermore, it was found that the grown of the bismuth oxide film on polymer matrices in the hydrothermal environment was selective to the types of polymer matrices. Our design can provide a reference to construct other photoactive functional films on polymer matrices and further collaborative applications and have the potential application prospects in the building and medical field.

AIEgens have been widely applied in the fields involving solid and aggregation states. However, the preparation of AIEgens with high brightness to obtain the optimum AIE performance remains a challenge. In this article, a finely structural design strategy for the creation of ultrabright AIEgens has been reported based on Ir(III) complexes. By stepwise heightening the motion activity of substituents, the AIE property of Ir(III) complexes can be activated with dramatically improved photoluminescence quantum yields in solid state. The dipole moment vector of substituents and the triplet lifetime of Ir(III) complexes were applied to verify the motion activity of substituents theoretically and experimentally. In addition, by the combination of AIE-active Ir(III) complex IrppyDPBA and air permeable, optically transparent ethylcellulose, a hypersensitive luminescent oxygen sensing film with ultrafast quenching/recovery cycles in 6.1 s was developed. And the high-brightness AIE significantly improved the oxygen sensitivity of Ir(III) complexes. Furthermore, the expeditious and high-definition development of latent fingerprints on the substrates of tinfoil, plastic, steel, and glass was demonstrated by the high-brightness AIE of IrppyDPBA in 3 min. The fingerprint photographs developed by IrppyDPBA were intact and legible enough to allow display and analyze down to level 3 details. Noteworthily, the synergistic enhancement of the AIE property and the RTP nature of Ir(III) complexes on LFP development was for the first time demonstrated.

A novel amorphous FeOOH modified BiVO4 photocatalyst (A-FeOOH/BiVO4) was successfully produced and characterized by various techniques. The results showed that amorphous FeOOH with about 2 nm thickness evenly covered on BiVO4 surface, which caused resultant A-FeOOH/BiVO4 exhibiting higher visible light photocatalytic performance for producing O2 from water than BiVO4. When the covered amount of amorphous FeOOH was 8%, the resultant photocatalyst possessed the best photocatalytic performance. To find the reasons for the improvement of photocatalytic property, electrochemical experiments, DRS, PL and BET, were also measured, the experimental results indicated that interface effect between amorphous FeOOH and BiVO4 could conduce to migration of photogenerated charge, and exhibit stronger light responded capacity. These positive factors promoted A-FeOOH/BiVO4 presenting improved the photocatalytic performance. In a word, the combination of amorphous FeOOH with BiVO4 is an effective strategy to conquer important challenges in photocatalysis field.

Ternary MoS2/MoO3/C nanosheets were successfully synthesized via a chemical vapor deposition method. The hybrids were characterized by x-ray diffraction, scanning electron microscope, high-resolution transmission electron microscopy, raman and x-ray photoelectron spectroscopic methods. The as-obtained MoS2/MoO3/C nanosheets applied as an anode material for lithium-ion batteries, showed high initial discharge/charge capacities at current rates of 0.5C, 1640.9 mA h g−1 and 1393.8 mA h g−1 respectively, with initial coulombic efficiency of approximately 84.9%. The material exhibited superior rate capabilities, with specific discharge capacities of 1240.2 mA h g−1, 1048.5 mA h g−1, 917.2 mA h g−1, 742.3 mA h g−1, 663.6 mA h g−1, 601.8 mA h g−1 and 593.4 mA h g−1 at current rates of 0.2C, 0.4C, 1C, 4C, 8C, 12C and 15C, respectively. This superior electrochemical performance was mainly due to the uniformly-distributed MoS2 nanosheets and to highly graphitized carbon, which not only mitigated mechanical stress during repeated cycling, but also provided good conductivity.

In this work, polyacrylonitrile (PAN) nanofiber separator is fabricated directly on the surface of the graphite anode of lithium-ion batteries, resulting in an integrated separator/anode assembly (S A A). On one hand, the porous structure and polar surface of PAN nanofiber separator enable the S A A with superior electrolyte affinity and wettability. On the other hand, the interlocking structure at the interface between graphite anode and nanofiber separator enhances the mechanical and thermal stabilities of the separator as well as the interface compatibility. As a result, the S A A possesses an electrolyte contact angle of about 0 o and a thermal shrinkage of less than 2% at 150 °C for 0.5 h, resulting from the coupling effect between nanofiber separator and graphite anode. The above advantages endow the LiCoO2/S A A full cell with better C-rate (capacity retention 44.3% at 32.0 C compared with that at 0.5 C) and cycling performances (capacity retention 98.0% after 200 cycles at 0.2 C) as well as higher thermal resistance compared with those of the common LiCoO2/polyolefin separator/graphite battery. Consequently, this work provides an advanced separator/anode assembly and the corresponding fabrication method, which may be a new strategy for improving the charge-discharge performance and assembly efficiency of lithium-ion batteries.

MoS 2 /C nanocomposite with a multilayered sandwich structure based on few-layered MoS 2 and carbon layers in an alternating sequence, was successfully synthesized through a one-step synchronized carbonization and sulfuration method. The hybrids were characterized by X-ray diffraction, High-resolution transmission electron microscopy, Atomic force microscope, Raman and X-ray photoelectron spectroscopic methods. The as-obtained MoS 2 /C nanocomposite applied as lithium-ion batteries anode materials, showed a high initial discharge and charge capacities of 1678.5 and 1386.0 mAh g −1 , respectively. High specific reversible capacity is maintained at fast C rates, e.g., 1390, 1223, 1017, 566, and 450 mAh g −1 at 0.1C, 0.6C, 3C, 10C and 20C, respectively. The good performance of the composite is mainly attributed to the unique few layered composite architectures, which can improve ion/electron transportation and prevent aggregation and restacking during the lithiation/delithiation process.

A multi-layer-cake WS2/C nanocomposite was successfully synthesized via an intercalation-transformation method, in which few-layered WS2 and carbon were sandwiched in an alternating sequence. As a benefit of the electronic conductivity enhanced by the interlayer carbon and the unique "regular" and "alternate" architecture, the WS2/C nanocomposite showed promising performance as anode material for lithium-ion batteries. The nanocomposite demonstrated a high capacity of 829.4 mAhg-1 at 0.3 Ag-1 after 140 cycles and it could still deliver a stable capacity of about 326.8 mAhg-1 at a current density of 8.0 Ag-1.

A four-angle star-like Co–Al mixed metal oxide (CoAl-MMO)/BiVO4 heterojunction has been synthesized via a hydrothermal method and following sintering. The CoAl-MMO/BiVO4 is derived from CoAl-LDHs/BiVO4, in which CoAl-LDHs leads to a distribution of amorphous CoAl-MMO. The CoAl-MMO loading on BiVO4 greatly enhances visible light absorption, improves charge separation by band offset charge transfer, and makes flat band potential more negative. The three effects together result in excellent photocatalytic activity. Under visible light irradiation, desulfurization efficiency of thiophene has achieved up to 98.58% on CoAl-MMO/BiVO4 with molar ratio of 0.3 : 5.

Although micro-mesoporous composite molecular sieves have received significant attention due to their desirable properties, they still lack systematic studies on their crystallization process to achieve controllable synthesis of composite molecular sieves. In this study, a series of Y/SBA-15 micro-mesoporous composite molecular sieves with different porous structures were synthesized by tuning nucleation temperature, based on epitaxial growth on the outer surface of the Y-type crystal particle. All composite molecular sieves were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), and transmission electron microscope (TEM). Moreover, the effect of nucleation temperature on the structure of composite molecular sieves was investigated, while the crystallization mechanism was also explored. Furthermore, the performance of the molecular sieves on isomerization of n-pentane was investigated, the results suggested that the isomerization selectivity was positively correlated with regularity degree of the mesoporous porous structure, where the highest isomerization reached 95.81%. This work suggests that nucleation temperature plays a key role in structures of micro-mesoporous composite molecular sieves, providing a solid basis for the further development of functional composite molecular sieves.

Three Ir(III) complexes IrC1, IrC2, and IrC3 substituted with 4-(diphenylamino)phenyl (TPA), 4-(9H-carbazol-9-yl)phenyl (Cz1), and 9-phenyl-9H-carbazol-3-yl (Cz2) moieties were prepared and fully characterized as phosphorescent emitters. In comparison with Ir(ppy)3, introduction of TPA, Cz1, and Cz2 moieties strongly improved the oxygen sensitivities of IrC1–IrC3. Short-decayed IrC1 with I0/I100 of 168.6 and KappSV of 202.2 bar−1 in THF exhibited the highest sensitivity for oxygen. TPA and Cz moieties caused remarkable collision radius variations of the Ir(III) complexes with 2.13 ± 0.08 for σIrC1/σIr(ppy)3, 1.24 ± 0.06 for σIrC2/σIr(ppy)3, and 1.54 ± 0.08 for σIrC3/σIr(ppy)3. For demonstrating the dependence of oxygen sensitivity on the molecular structure of the oxygen-sensitive probes (OSPs), the delocalization of spin populations (DSPs) has been applied for the first time to confirm the collision radius variations of Ir(III) complexes. Remarkable DSPs were found on the TPA, Cz1, and Cz2 moieties with the spin population (percentage of the spin population) of 0.23210 (11.61%), 0.08862 (4.43%), and 0.13201 (6.60%), respectively. And strong linear correlations (R2 = 0.997) between the collision radius variations and spin population on TPA and Cz moieties were apparent. The DSPs could be used to describe the dependence of oxygen sensitivity on the molecular structure of the OSPs. For achieving real-time oxygen sensing, the photostability, oxygen sensing performance, and operational stability of IrC1–IrC3 and Ir(ppy)3 immobilized in ethyl cellulose (EC) were investigated. The IrC1-EC film demonstrated outstanding photostability after 60 min of irradiation and excellent operational stability for continuous oxygen monitoring with no attenuation of the original emission intensity in 4000 s. This study quantified and analyzed the dependence of oxygen sensitivity on the molecular structure of Ir(III) complexes for the first time and illustrated a feasible approach to achieve high-efficiency sensors for real-time monitoring of oxygen.

AIE-active luminogens are attractive for bioimaging, sensors, and optical detections. However, controllably switching and adjusting the AIE activity of luminogens in aqueous media to perform the best of AIE performance under appropriate water fraction remains a challenge. Herein, we report the first case of switchable and adjustable AIE activity based on Pt(II) complexes. The AIE activity of Pt(II) complexes in aqueous media can be flexibly switched and adjusted via finely tuning the rotation activity of the substituents. And the rotation activity of the substituents have been experimentally confirmed by the luminescent lifetimes and theoretically verified by the dipole moments of Pt(II) complexes. Furthermore, luminescent oxygen sensing films were constructed by combining the AIE-active Pt(II) complexes with commercially available, low-cost ethyl cellulose (EC). With the attenuation of EC film thickness, swift-responding quenching/recovering cycles (7.7 s) of the PtTPA-EC(N10) oxygen sensing film were demonstrated. And the controllable AIE property of Pt(II) complexes can effectively improve the oxygen sensitivity and the homogeneity of oxygen sensing films.

Although Na-ion batteries have attracted considerable attention as a competitive alternative to Li-ion batteries, the development of anode materials with satisfactory performances is still in its infancy, which leads to the increasing interest in the nanoscale design of the structure and chemistry of electrode materials. In this study, the confinement effect and template role provided by metal–organic supramolecular frameworks are exploited to fabricate hollow carbon nitride hierarchical microspheres with ultrafine N-doped MoC (MoCxNy) uniformly dispersed within the network. In the special nanoarchitecture, the carbon nitride matrix with the hollow structure can buffer the volume change of MoCxNy nanoparticles, inhibit their aggregation and improve the conductivities during sodiation/desodiation. Moreover, the pyrolysis of melamine ligands under confinement induces the incorporation of N-dopant into the lattice of molybdenum carbides, which further promotes the electrochemical activity of molybdenum carbides. Benefiting from these combined effects, the as-fabricated hybrids show remarkable cycle stability with a specific capacity of 410 mA h g−1 after 200 cycles at 0.16 A g−1 current. High specific discharge capacities are maintained at high current density, e.g. 370 mA h g−1, 310 mA h g−1, 240 mA h g−1 and 190 mA h g−1 at 0.33 A g−1, 0.5 A g−1, 0.67 A g−1 and 0.83 A g−1, respectively.

Specific surface area, hierarchical porosity and heteroatom doping have been proved to be desirable for carbon electrode materials in advanced super-capacitors. In this study, homogeneous sulphur-doped porous carbon materials (L-HPCs) with a unique hierarchical porous nanostructure have been prepared by the combination of the two-dimensional interlayer confinement effect of a layered double hydroxide (LDH) and KOH activation method. XRD, SEM, TEM, BET, EIS, cyclic voltammetry and the constant current charge–discharge test were used to investigate the morphology, structure, surface properties and electrochemical performances of the carbon materials. The L-HPCs fabricated by this method have a large specific surface area of 2154.0 m2 g−1 and contain plenty of micropores and mesopores, which arise from the carbonisation of organic polymers, the presence of LDH and the catalytic effect of iron in LDH layers in the calcination process. The L-HPCs serving as an electrode material for super-capacitors exhibited a specific capacitance as high as 259 F g−1 at 1 A g−1 in 6 M KOH electrolyte. This excellent electrochemical performance might be due to the high surface area, high pore volume and hierarchical porous structure of the carbon materials, which provide a quick ion transfer pathway to electrolyte access into the microporous area. At the same time, the doping of heteroatoms can improve the conductivity of the electrode materials.

Nitrogen (N) and sulfur (S) co-doped porous carbon materials (NSPCs) have been prepared by the two-dimensional interlayer confinement effect of a layered double hydroxide (LDH). The NSPCs fabricated by this method have a large specific surface area of 1493.2 m2 g−1 and contain plenty of micropores and mesopores, which arise from either the carbonization of organic polymers and the catalytic effect of iron in LDH layers in the calcination process, or the elimination of metal oxides produced by the LDH hosts in acid dissolution. The prepared material exhibits an excellent reversible specific capacity of 1175 mA h g−1 at 0.5C after 120 cycles. High specific discharge capacities are maintained at fast C rates, e.g. 765, 600, 510, 419, 398, 360, and 326 mA h g−1 at 1, 2, 6, 15, 20, 30 and 60C, with 15 cycles at each step. We found that the improved electrochemical performance is due to the large quantity of edge defects, and the micropores and mesopores in the material which can provide extra Li storage regions.

N vacancy modified g-C3N4 nano-fragments were facilely prepared through thermal treatment method. The declined size and thickness of resultant g-C3N4 nano-fragments make it possess quantum confinement effect. The synergistic effect of N vacancy and quantum confinement effect endows resulting g-C3N4 nano-fragments with bigger surface area, stronger light response ability and improved migration effect of photoinduced charge. Not only that, the existence of quantum confinement effect remedies the shortcoming that reduced intrinsic conduction band potential was caused by N vacancy, and the conduction band position was easily adjusted. When N vacancy modified g-C3N4 nano-fragments were used to produce H2, the H2 evolution rate of the best sample (nano-CN5) was 5.9 folds more than bulk g-C3N4 and kept admirable stability of performance, structure and feature. Clearly, the present work develops a useful strategy for adjusting conduction band position of g-C3N4 and a meaningful thought for changing band gap of other photocatalysts.

As a popular material synthesis method, spatially confined reactions have been gradually recognised for their excellent performance in the field of current materials synthesis. In recent years, molybdenum-based catalysts have gradually gained recognition due to high natural reserves of Mo, its low cost, and many other advantages, and they have wide applications in the area of functional materials, especially in topical areas such as batteries and electrocatalysts. In this context, spatially confined reactions have become widely to obtain various types of molybdenum-based electrode materials and electrocatalysts which result in an excellent morphology, structure, and performance. In this review, the concept of a spatially confined reaction system and the electrochemical application (electrode materials and electrocatalyst) of molybdenum-based materials synthesised in this way are comprehensively discussed. The current problems and future development and application of molybdenum-based materials are also discussed in this review.

A facile process was developed to synthesize MoS 2 /MWNT composites. The experimental results show that MoS 2 /MWNT composite with molar ratio of 1:4 exhibits the highest specific reversible capacity of 1112.5 mAh/g at a current of 100 mA/g after 90 cycles at different current densities. The excellent electrochemical properties of MoS 2 /MWNT composites are attributed to the synergistic effects of layered MoS 2 and MWNT.

Molybdenum oxide is an attractive anode material for lithium ion batteries because of its environmental benignity and high capacity. However, molybdenum oxide suffers from serious capacity fading caused by large volume changes and poor rate capability due to low conductivity. In this work, ultrathin N-doped carbon layer encapsulated MoO3 nanosheets have been synthesized by a simultaneous pyrolysis–reduction process of dodecylamine-intercalated MoO3 composites at 600 °C under a nitrogen atmosphere. This special 2D nanosheet morphology can greatly shorten the diffusion length of both electrons and ions, which can ensure the fast kinetics of Li+ intercalation and deintercalation, resulting in high rate performance. Furthermore, N-doped carbon encapsulated MoO3 nanosheets exhibited good electrical conductivity, uniform dispersion and ultrathin thickness. On the basis of these combined effects, the as-fabricated nanosheets can reach high initial charge and discharge capacities of 1610 and 1359 mA h g−1, respectively, and show remarkable cycle stability with a specific capacity of 1250 mA h g−1 after 60 cycles at 0.3C rate. High specific discharge capacities are maintained at fast C rates, e.g., 1370, 1010, 940, 610, 490 and 370 mA h g−1 at 0.3C, 1C, 2C, 4C, 10C, and 20C, respectively.