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Flexible graphite film (FGF), as a traditional interface heat dissipation material, has high anisotropy. It is a challenge to enhance both in-plane and through-plane thermal conductivity of FGF. For this reason, the effects of oxygen content, layer spacing, density and particle size on the in-plane and through-plane thermal conductivity of FGF were studied by both molecular simulation and experimental investigation. The simulation results indicate that the ways to improve the thermal conductivity of FGF include reducing oxygen content and layer spacing, increasing the density and matching the size of graphite sheets. The FGF prepared from room temperature exfoliated graphite (RTFGF) has a wide range of adjustable density (1.3–2.0 g/cm3) and thickness (50–400 μm). The thermal conductivity of the RTFGF is significantly improved after heat treatment owing to reduced oxygen content and layer spacing, which is consistent with the simulation results. Moreover, RTFGF with both high in-plane (518 W⋅m−1⋅K−1) and through-plane (7.2 W⋅m−1⋅K−1) thermal conductivity can be obtained by particle size matching of graphite.

Two-dimensional transition metal dichalcogenides (TMDCs) have been regarded as an intriguing platform for exploring novel physical phenomena and optoelectronic devices due to their excitonic emission characteristics derived from the atomic thin thickness and reduced dielectric screening effect. Notably, monolayer TMDCs with a direct bandgap exhibiting strong photoluminescence (PL) are promising candidates for the light-emitting devices, while the interlayer excitons in heterostructures hold great potential for the photonic chips and optical communication applications. However, the non-ideal photoluminescent intensity and quality due to the ultrathin thickness and high defect density of experimentally obtained monolayer TMDCs limit the further development for the light-emission applications. Here, we summarize the research progress on the PL manipulation of the excitonic emission in TMDCs, where the PL intensity enhancement and emission wavelength regulation are included. The concept and characteristics of excitons are overviewed firstly, followed by the discussion on the evaluation and characterization of excitonic emission. The state-of-the-art progress on the manipulation of the neutral excitons and interlayer excitons PL are then summarized. Finally, the challenges and prospects are proposed.

Sodium ion hybrid capacitors (SIHCs) are regarded as advanced power supply systems. Nevertheless, the kinetics imbalance of cathode and anode suppresses the further performance improvement of SIHCs. The carbonaceous anode materials are promising and many strategies have been utilized to increase the capacity of sloping region or accelerate the reaction rate of plateau region. However, it is still challenging to simultaneously realize high mesopore/micropore volume ratio, large interlayer distance (>0.37 nm), and abundant and favorable heteroatoms-doping by a simple method. Herein, we report N, P, O ternary-doped mesoporous carbon (PNPOC-T, T = 700, 800 or 900) with large interlayer distance (∼0.4 nm) as anode materials. The PNPOC-T were prepared by a simple in-situ polymerization of aniline and phytic acid on the exfoliated graphitic nitrogen carbide (g-C3N4) and subsequent carbonization. The obtained PNPOC-800 exhibits an excellent rate performance (101.5 mA·h ·g−1 at 20 A·g−1), which can be attributed to the high surface-controlled capacitive behavior ratio and rapid ion diffusion. The optimum SIHCs display a high energy density of 105.48 W·h·kg−1 and a high power density of 13.59 kW·kg−1. Furthermore, the capacitance retention rate of SIHCs can reach 87.43% after 9 000 cycles at 1 A·g−1.

Transition metal sulfides (TMSs) are widely recognized for their potential as anode materials in the development of flexible lithium-ion capacitors (FLICs) owing to their high theoretical capacity. However, their practical application has been significantly limited by rapid capacity decay and sluggish kinetics associated with TMS volume variation. In response to these challenges, we have prepared ZnS/CuS nanoparticles embedded in continuous and multichannel carbon fibers (CFs). This was achieved through a process involving blow-spinning and subsequent sulfidation. Notably, the electrochemical performance of these materials was largely improved, owing to the synergistic effect of bimetallic sulfides. The ZnS/CuS-CF anode material demonstrated a high specific capacity of over 900 mAh g−1 at a current density of 0.2 A g−1. Furthermore, it exhibited superior rate capacity (300 mAh g−1 at 20 A g−1) and excellent cyclic stability, maintaining its performance over 1000 cycles at 10 A g−1. We also prepared lithium-ion capacitors (LICs) using the same method. These LICs exhibited a maximum energy density of 136 Wh kg−1, a high power density of 43.5 kW kg−1, and an impressive cyclic stability over 4000 cycles. In addition, the FLICs, when configured in the form of a pouch cell, demonstrated significant potential for the development of smart, flexible electronic devices.

Summary: Constructing high-performance enzyme-free biosensors for detecting glucose is essential to preliminary diabetes diagnosis. Here, copper oxide nanoparticles (CuO@Cu2O NPs) were anchored in porous nitrogen-doped reduced graphene oxide (PNrGO) to construct CuO@Cu2O/PNrGO/GCE hybrid electrode for sensitive detection of glucose. Benefiting from the remarkable synergistic effects between the multiple high activation sites of CuO@Cu2O NPs and the dramatic properties of PNrGO with excellent conductivity and large surface area with many accessible pores, the hybrid electrode possesses outstanding glucose sensing performance that is far superior to those of pristine CuO@Cu2O electrode. The as-fabricated enzyme-free glucose biosensor displays prominent glucose sensitivity of 2,906.07 μA mM−1 cm−2, extremely low limit of detection of 0.13 μM, and wide linear detection of 3 μM–6.772 mM. In addition, excellent reproducibility, favorable long-term stability, and distinguished selectivity are obtained in the glucose detection. Importantly, this study provides promising results for continuous improvement of non-enzyme sensing applications.

Diabetes mellitus (DM) has grown up to be an important issue of global public health because of its high incidence rate. About 25% of DM patients can develop diabetic foot/ulcers (DF/DFU). Diabetic kidney disease (DKD) is the main cause of end-stage kidney disease (ESKD). DF/DFU and DKD are serious complications of DM. Therefore, early diagnosis and timely prevention and treatment of DF/DFU and DKD are essential for the progress of DM. The clinical diagnosis and staging of DKD are mostly based on the urinary albumin excretion rate (UAER) and EGFR. However, clinically, DKD patients show normoalbuminuric diabetic kidney disease (NADKD) instead of clinical proteinuria. The old NADKD concept is no longer suitable and should be updated accordingly with the redefinition of normal proteinuria by NKF/FDA. Based on the relevant guidelines of DM and CKD and combined with the current situation of clinical research, the review described NADKD from the aspects of epidemiology, pathological mechanism, clinical characteristics, biomarkers, disease diagnosis, and the relationship with DF/DFU to arouse the new understanding of NADKD in the medical profession and pay attention to it.

Exfoliated graphite (EG) is promising oil sorbent as well as an intermediate product for the preparation of flexible graphite films (FGFs). It has been a critical challenge to energy conservation and pollution abatement for the traditional EG production technique. Here, we propose a simple and effective preparation method to acquire EG in which flake graphite is intercalated and exfoliated at room temperature, not involving any pollutant emission. The influence factors in the preparation process were explored, such as the amount of H2SO4 and H2O2, the temperature for the preparation of room temperature exfoliated graphite (RTEG). In contrast to the EG by high temperature exfoliation (HTEG), RTEG exhibits a homogeneous structure and a significantly increased volume and surface area. Moreover, EG blocks with high oil sorption capacity and excellent reuse performance can be obtained by RTEG method. Especially, FGFs fabricated by RTEG has high flexibility, thermal conductivity and electrical conductivity. It suggests that this environment-friendly technology is suitable for large-scale industrial implementation of graphite-based oil sorbents and flexible materials.

Metal-organic framework (MOF)-derived nanoporous carbons (NPCs) and porous metal oxide nanostructures or nanocomposites have gathered considerable interest due to their potential use in supercapacitor (SCs) applications, owing to their precise control over porous architectures, pore volumes, and surface area. Bimetallic MOFs could provide rich redox reactions deriving from improved charge transfer between different metal ions, so their supercapacitor performance could be further greatly enhanced. In this study, “One-for-All” strategy is adopted to synthesize both positive and negative electrodes for hybrid asymmetric SCs (ASCs) from a single bimetallic MOF. The bimetallic Zn/Co-MOF with cuboid-like structures were synthesized by a simple method. The MOF-derived nanoporous carbons (NPC) were then obtained by post-heat treatment of the as-synthesized Zn/Co-MOF and rinsing with HCl, and bimetallic oxides (ZnCo2O4) were achieved by sintering the Zn/Co-MOF in air. The as-prepared MOF-derived NPC and bimetallic oxides were utilized as negative and positive materials to assemble hybrid ASCs with 6 M KOH as an electrolyte. Owing to the matchable voltage window and specific capacitance between the negative (NPC) and positive (ZnCo2O4), the as-assembled ASCs delivered high specific capacitance of 94.4 F/g (cell), excellent energy density of 28.6 Wh/kg at a power density of 100 W/kg, and high cycling stability of 87.2% after 5,000 charge-discharge cycles. This strategy is promising in producing high-energy-density electrode materials in supercapacitors.

The key to solving environmental and energy issues through photocatalytic technology requires highly efficient, stable and eco-friendly photocatalysts. Graphitic carbon nitride (g-C3N4) is one of the most promising candidates except for its limited photoactivity. In this work, a facile and scalable one-step method is developed to fabricate an efficient heterostructural g-C3N4 photocatalyst in situ coupled with MoS2. The strong coupling effect between the MoS2 nanosheets and g-C3N4 scaffold, numerous mesopores and enlarged specific surface area helped form an effective heterojunction. As such, the photocatalytic activity of the g-C3N4/MoS2 is more than three times higher than that of the pure g-C3N4 in the degradation of RhB under visible light irradiation. Improvement of g-C3N4/MoS2 photocatalytic performance is mainly ascribed to the effective suppression of the recombination of charge carriers.

Sodium-ion capacitors (NICs) are considered an important candidate for large-scale energy storage in virtue of their superior energy–power properties, as well as availability of rich Na+ reserves. To fabricate high-performance NIC electrode material, a hydrothermal method was proposed to synthesize sulfur-doped reduced graphene oxide (SG), which exhibited unique layered structures and showed excellent electrochemical properties with 116 F/g capacitance at 1 A/g as the cathode of NICs from 1.6 V to 4.2 V. At the power–energy density over 5000 W/kg, the SG demonstrated over 100 Wh/kg energy density after 3500 cycles, which indicated its efficient durability and superior power–energy properties. The addition of a sulfur source in the hydrothermal process led to the higher specific surface area and more abundant micropores of SG when compared with those of reduced graphene oxide (rGO), thus SG exhibited much better electrochemical properties than those shown by rGO. Partially substituting surface oxygen-containing groups of rGO with sulfur-containing groups also facilitated the enhanced sodium-ion storage ability of SG by introducing sufficient pseudocapacitance.

One antibacterial material was prepared from exfoliated graphite (EG) decorated with silver nanoparticles (AgNPs). The EG was prepared by the graphite intercalated compound process, AgNPs were prepared by chemical reduction of AgNO3 in the presence of NaBH4. The AgNPs-loaded EG (Ag-EG) composite was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), nitrogen adsorption, mercury intrusion porosimetry, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The antibacterial effect of the Ag-EG was evaluated by using the zone of inhibition method. The loaded AgNPs were highly dispersed on EG sheets and most of them have a size less than 10 nm. The Ag loading slightly increased the surface area of EG. It is shown that the Ag-EG had antibacterial activity and anti-adhesion properties against Pseudomonas aeruginosa and Staphylococcus aureus. It suggests that Ag-EG composites could be used in a variety of industrial applications that require an antibacterial effect.

LiMnPO4 with olivinestructure which is the promising candidate for high voltage cathode material was synthesized by hydrothermal method. In order to synthesize high purity and well-defined LiMnPO4, several precursors for Li, Mn, and P sources and hydrothermal reaction parameters including temperature and [H2O]/[Mn] value are optimized. By analyzing the structure, Mn valence, morphology, and chemical ratio via XRD, XPS, Raman, SEM, and ICP LiMnPO4 synthesized from manganese acetate tetrahydrate have single phase of LiMnPO4 without impurity and showed charge and discharge reaction caused by Mn2+/Mn3+ redox. Specific capacity of synthesized LiMnPO4 grew up during cycling. Moreover, when hydrothermal temperature was set at 150°C and [H2O]/[Mn] value was set at 15, discharge capacity as high as 70 mAh/g was obtained at 1/20 C rate.

Well-defined organic nanostructures with controllable size and morphology are increasingly exploited in optoelectronic devices. As promising building blocks, porphyrins have demonstrated great potentials in visible-light photocatalytic applications, because of their electrical, optical and catalytic properties. From this perspective, we have summarized the recent significant advances on the design and photocatalytic applications of porphyrin-based nanostructures. The rational strategies, such as texture or crystal modification and interfacial heterostructuring, are described. The applications of the porphyrin-based nanostructures in photocatalytic pollutant degradation and hydrogen evolution are presented. Finally, the ongoing challenges and opportunities for the future development of porphyrin nanostructures in high-quality nanodevices are also proposed.

The iodine-doped Bi2WO6 (I-BWO) photocatalyst was prepared via a hydrothermal method using potassium iodide as the source of iodine. The samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM) and selected area electron diffraction (SAED), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectroscopy (DRS), and photoluminescence (PL) spectroscopy. The photocatalytic activity of I-BWO for the degradation of rhodamine B (RhB) was higher than that of pure BWO and I2-BWO regardless of visible light (>420 nm) or ultraviolet light (

The heterostructured TiO2/N-Bi2WO6 composites were prepared by a facile sol-gel-hydrothermal method. The phase structures, morphologies, and optical properties of the samples were characterized by using X-ray powder diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), energy dispersive spectroscopy (EDS), and UV-vis diffuse reflectance spectroscopy. The photocatalytic activities for rhodamine B of the as-prepared products were measured under visible and ultraviolet light irradiation at room temperature. The TiO2/N-Bi2WO6 composites exhibited much higher photocatalytic performances than TiO2 as well as Bi2WO6. The enhancement in the visible light photocatalytic performance of the TiO2/N-Bi2WO6 composites could be attributed to the effective electron-hole separations at the interfaces of the two semiconductors, which facilitate the transfer of the photoinduced carriers.

Viscose rayon-based activated carbon fibre (ACF) was prepared by CO 2 activation and the pore structure of all samples characterized via nitrogen adsorption at −196°C. The influence of temperature on the adsorption of organic vapour onto ACF was studied by gravimetric methods. The results showed that the adsorption capacity towards organic vapour decreased with increasing temperature at a given concentration. The larger the specific surface area of the ACF, the greater the extent to which its vapour adsorption performance was affected by temperature. It is suggested that an ACF of a relatively low burn-off would be suitable for adsorption at higher temperatures.

The adsorption characteristics of volatile organic compounds (VOCs) on viscose rayon-based activated carbon fibres (ACFs) were investigated. ACFs with specific surface areas of 640 m 2 /g and 1460 m 2 /g were used to adsorb trace volatile organic compounds in nitrogen streams at atmospheric pressure at or near room temperature (25°C and 30°C). The experimental results showed that ACFs with different surface areas exhibited different dynamic adsorption behaviours at or near room temperature.

Viscose rayon-based activated carbon fibres (ACFs) with low and high specific surface areas were treated with conc. HNO 3 , 30 wt% H 2 O 2 and air at different temperatures. The pore textures and surface chemistries of the samples were characterized by nitrogen adsorption at 77 K and X-ray photoelectron spectroscopic (XPS) methods. The adsorption of traces of volatile organic compounds (VOCs), i.e. benzene and methyl ethyl ketone (MEK), in nitrogen streams on the samples wwa measured by a gravimetric method. The results showed that the surface oxygen complexes and pore textures of all the oxidized ACFs were modified and differed depending on whether oxidation had been conducted under gaseous or solution conditions. ACFs with different specific surface areas possessed different adsorption characteristics towards VOC vapours after subjection to oxidation treatment.