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Porous carbon is considered as one of the most promising electrode materials for supercapacitors. In this work, we report a simple two-step preparation of porous carbon materials based on MnO2-coated and N-doped pinecone, which was synthesized by carbonization and hydrothermal process. After electrochemical analysis, the prepared 3-N-PC@MnO2 electrode exhibited optimal electrochemical performance. At a current density of 1 A/g, the specific capacitance of 3-N-PC@MnO2 was as high as 167.8 F/g in a voltage window of 0–1 V. After being assembled into an asymmetric supercapacitor with the PVA/Na2SO4 quasi-solid electrolyte under the current density of 1 A/g, the energy density could reach 20.42 Wh/kg, the power density could achieve 799.9 W/kg, and its capacitance remained 84.5% after 3000 cycles, showing remarkable electrochemical performance.

In recent years, as a flexible electrode material, melamine foam has attracted more and more attention from researchers in the field of wearable energy storage devices. In addition, certain components are loaded on it to improve electrochemical performance and further promote its advantages. Here, we first carbonized commercial melamine foam in N2 atmosphere to form in situ doping and then used a simple hydro-thermal reaction to uniformly load MnO2 nanosheet arrays on its three-dimensional framework. For the resulting electrode material, the specific capacitance was as high as 230.3 F/g under the current density of 1 A/g. With the voltage window of 0–2.2 V, the energy density of the assembled quasi-solid supercapacitor reached 29.73 Wh/kg with the power density of 1636.9 W/kg, showing great electrochemistry performance and application prospects.

As one of the most promising electrode materials for supercapacitors, MnO2 has the problems of low voltage window and poor conductivity. It has been shown that Al-doped MnO2 can effectively improve the voltage window and specific capacitance, and polyaniline loading can further bring higher specific capacitance. Polyaniline-supported Al-doped MnO2 carbon cloth-based flexible electrode material (PANI@Al-MnO2@CC) was prepared by hydrothermal reaction and in-situ polymerization. Compared with MnO2 electrode material, the working voltage window of PANI@Al-MnO2@CC is increases to 1.25 V, the area specific capacitance can be as high as 1016 mF cm−2, and still maintain 80.1% of the original value at 20 mA cm−2 after 5000 cycles. Furthermore, the voltage window of the flexible symmetrical supercapacitor made of the material can reach 0–2.4 V, and has a super large area specific capacitance of 149.75 mF cm−2 and a high energy density of 1.60 mWh cm−3 at 6 mA cm−2.

The point of this review is mainly focusing on the safety and practicability of solid-state lithium ion battery. And this review emphatically discusses and analyzes these practical manufacturing methods and strategies by illustrating some novel and excellent reported examples instead of barely collecting and classifying these new materials over the years. Based on the current industrial technology and market requirements, we summarize four types of most practical solid-state electrolytes (polymer gel, PEO-based, garnet-type and sulfide-type electrolyte) whose potential of application, strategy of improvement and possibility of mass production are all analyzed in this review. Li ion transport mechanisms in different electrolytes, which are commonly accepted in recent years, are summarized and stated as well. Besides, the key interfacial problems of electrolytes and electrodes for solid batteries is emphatically discussed and we also sort out some useful methods for actual production. And there are some interesting and novel content in this paper, which is that the lithium metal is not considered as an anode material because we think that is not realistic and economical for industrial manufacture in recent years and the polymer gel is analyzed to be a great transition electrolyte from liquid electrolyte batteries to all-solid-state batteries.

For a higher safety and energy density, solid-state electrolytes with a better mechanical strength and thermal and electrochemical stability are a perfect choice. To improve the performance of PEO, using low-cost inert fillers may bring amorphous regions but limits easily appear. This paper aims to promote a network of SiO2 nanowires by applying a novel in situ crosslinking structure composed of PEA, γ-GPS and mPEG with siloxane segments as the junctions. The modified network can significantly reduce the crystallinity and glass transformation temperature, which also reduces the activation energy of ion transfer. Crosslinking can be highly influential as a comprehensive function of segment relaxation and ion complexation. The optimal sample (PEO–SNWAKP20) possesses a conductivity of 2.52 × 10−4 at 40 °C and a wide electrochemical window of 5.1 V. This unique structure also brings ideal shape stability under high temperatures, thus realizing stable cycling for 800 h at 0.1 mA cm−2. The rate and cycling performance of the LiFePO4 cell are also improved, achieving a maximum of 131.2 mAh g−1 under 0.5C with 89.3% retention after 50 cycles at 50 °C, realizing 24% improvement compared with single SNW reinforcement. By modifying the electrode, its performance can be further raised to 154 and 130.4 mAh g−1 under 0.5C and 1C, respectively, reserving 97.9% of its capacity after 100 cycles. This may inspire new strategies for synthesizing high-performance composite electrolytes.

The drawback of traditional capacitors with low energy density forces people to develop high-performance supercapacitor materials. Herein, the Al-doped MnO2 @ carbon cloth is selected as the ideal electrode material. A typical hydrothermal reaction can be used to synthesize Al-doped MnO2 @ carbon cloth at 150 °C for 4 h. Its operating window can be successfully expanded from 0–0.8 to 0–1.2 V, and the areal-specific capacitance reaches 1043 mF cm−2, keeping 91.1% of the original after cycling 5000 times at a current density of 20 mA cm−2. Using the electrode materials designed above, the flexible symmetrical supercapacitor is successfully assembled. This device shows a greater operating window of 0–2.3 V, a superior large areal-specific capacitance of 521.91 mF cm−2, and the energy density remarkably reaches 4.72 mWh cm−3. After 100 bending cycles, there is also basically no loss in performance. This study highlights the promising prospects of the improvement of MnO2 @ CC materials.

MnO2@bamboo leaf (BL) carbon composites have been prepared by a hydrothermal method, wherein, the BL porous carbon structure was based on BLs. The MnO2@BL composites were characterized by SEM, TEM, XRD, Raman, XPS, and TGA. The electrochemical properties of the composites were investigated in a three-electrode system using 1 M Na2SO4 aqueous solution as an asymmetric supercapacitor electrolyte. Electrochemical measurements showed that the MnO2@BL composites can be applied in asymmetric supercapacitors and exhibited a good cycling stability with a capacitance retention ratio of 85.3% after 5000 cycles (at 0.5 A g-1). The MnO2@BL composites were promising materials for application in supercapacitors.

Subnanometric Pd clusters confined within zeolite crystals was fabricated using zeolitic seeds with premade [Pd3Cl(PPh2)2(PPh3)3]+ clusters under hydrothermal conditions. Characterization of the Pd3@Beta catalysts indicate that the Pd clusters confined in the channels of Beta zeolite exhibit better dispersion and stronger interaction with the zeolite support, leading to stabilized Pd species after heat treatment by high temperature. In the model reaction of toluene combustion, the Pd3@Beta outperforms both zeolite-supported Pd nanoparticles prepared by conventional impregnation of Pd3/Beta and Pd/Beta. Temperatures for achieving toluene conversion of 5%, 50% and 98% of Pd3@Beta are 136, 169 and 187 °C at SV = 60 000 mL g−1 h−1, respectively. Pd3@Beta could also maintain the catalytic reaction for more than 100 h at 230 °C without losing its activity, an important issue for practical applications. The metal-containing zeolitic seed directed synthesis of metal clusters inside zeolites endows the catalysts with excellent catalytic activity and high metal stability, thus providing potential avenues for the development of metal-encapsulated catalysts for VOCs removal.

Porous colloidal hollow spheres have been applied to diversified fields over the past few decades. However, developing simple and efficient methods to prepare such porous hollow spheres with macro pores remains a challenge. To address this problem, we present a patchy templated synthesis route, which can be used to prepare such colloidal hollow spheres that have macro pores through the shells. This was achieved by using patchy poly(styrene-co-sodium styrenesulfonate) spheres as the template and poly(allylamine hydrochloride) as binding molecules. SiO2 can site-selectively only grow on one kind of patch, resulting in the formation of porous hollow spheres. The pore sizes can be tuned from ∼50 to 400 nm. The resulting porous hollow spheres have a Janus character so that Au nanoparticles can only be attached to the interior surfaces in situ, which can be used as catalytic microreactors and show the catalytic performance of pore size dependence.

The mechanical properties of concrete can degrade significantly under high temperature, posing a threat to the safety of structures. In this work, a novel bio-inspired cement-based composite material that can improve the fire resistance of engineering structures is put forward. This bio-inspired cementitious system, which functions in a manner similar to that of sweat glands and skin in the human body, consists of APP-PER-EN composite, synthetic reinforcing fibers, and concrete binder. The APP-PER-EN composite is mainly composed of ammonium polyphosphate, pentaerythritol, and melamine, with low-density polyethylene as the base material, which is prepared by melt compounding in a twin-screw extruder followed by grain cutting molding technique. At the micro level, multiple analysis methods are used, including X-ray diffraction, Fourier transform infrared ray, thermo-gravimetric analysis, differential scanning calorimeter, and scanning electron microscopy, to characterize the thermal and flame retardant behavior of this novel composite. At the macro level, the one-side heating tests indicate that the thermally triggered fire-resistant system can exhibit significant thermal insulation effect through melting, connecting, foaming, and overflowing. Therefore, the novel composite system is expected to exhibit a promising prospect in the fire resistance of engineering structures.

Carbon-based materials, as electrodes for supercapacitors, have attracted tremendous attention. Therefore, nitrogen-doped porous carbons (NPCs) were prepared through a facile carbonization/activation strategy by treating different mass ratios of melamine-urea-formaldehyde resin and KOH. It is clearly demonstrated that because of the introduction of KOH, the resulting NPCs were shown to have increased specific surface area and a rich pore structure, and the best sample possessed a large specific surface area of 2248 m2 g-1 and high N content, which contributed to the good electrochemical performance for supercapacitors. Accordingly, a three-electrode system assembles NPCs as an electrode using aqueous KOH solution; the specific capacitance was 341 F g-1 under the current density of 1 A g-1 and retained a specific capacitance of almost 92% after 5000 cycles. The maximum energy output for a symmetrical solid-state supercapacitor with NPCs as the electrode material was 9.60 W h kg-1 at 1 A g-1. NPCs have promising applications on high-performance supercapacitors and other energy-storage devices.

The development of simple and feasible methods to synthesize highly efficient adsorbents is the key to low-cost gas purification. Here we developed an in-situ amorphous cobalt template method based on the synergistic effect of precursor to synthesize nitrogen doped unimodal ultramicropores carbon nanosheets Co-NDPCs with high nitrogen content (up to 11.74%), large specific surface area (up to 1187 m2 g−1) and unimodal ultramicropore. As an adsorbent, the Co-NDPCs exhibit unprecedented C2H2, C2H6, C3H8 and CO2 uptake capacities of 6.7, 5.9, 7.4 and 5.6 mmol g−1, respectively, and the corresponding x/CH4 and CO2/N2 IAST selectivities are as high as 75.3, 65.9.1743.6, 11.4 and 74.7 at 298 K and 1 bar. More importantly, this method effectively avoids the defects of traditional activation or template method, such as corrosiveness, poor safety and complicated process, indicating that Co-NDPCs is a promising adsorbent for CH4/C2H2/C2H6/C3H8/CO2/N2 capture and separation.

The poly(3-hexylthiophene) - multiwalled carbon nanotube hybrid material (P3HT-MWCNT) was successfully prepared in the Cu(I)/DBU catalyst system via in-situ click reaction. The properties of P3HT-MWCNT were measured by FTIR, 1H NMR, UV-vis, XRD, TEM, SEM . The fluorescence spectrum of P3HT-MWCNT proved the covalent bond between P3HT and MWCNT, and P3HT could be coated on the surface of MWCNT. Compared with the physical blends of P3HT and MWCNT, P3HT-MWCNT prepared by click chemistry exhibited better thermal stability and a higher melting point of 243.2 °C. TG results also indicated that P3HT content of P3HT-MWCNT was 21.4%. It was expected to prepare novel organic-inorganic donor-acceptor hybrid material with good solubility, optical and thermal stability, which may be a promising material applied in preparation of organic photoelectron in the future.

Recently, design of cost-effective multifunctional electromaterials for supercapacitors and oxygen evolution reaction (OER) and enhancing their functionalities have become an emphasis in energy storage and conversion. Herein, a series of cheap and functional phosphate composites with different ratios of cobalt and nickel are synthesized using a simple polyalcohol refluxing method, and their excellent capacity and OER properties are systematically studied. Notably, owing to the different major role of Co and Ni elements in the phosphate composites for capacity and OER, the optimal electroconductibility, structural adjustment, electrochemical active sites, and activities for capacity and OER are obtained from the composites with the different ratios of Co/Ni. In addition, using high-capacity BiPO4 (BPO) as the negative electrodes, the new type of all-phosphate asymmetric supercapacitor (CNPO-40//BPO) shows a high energy density and reaches 36.84 W h kg-1 at a power density of 254.52 W kg-1. Its cyclic stability is also more excellent than that of the CNPO-40//AC device using commercial activated carbon as the negative electrodes. This study is beneficial to the more in-depth research on efficient dual-function electromaterials in capacity and OER and provides a high-efficient way to improve the practicality of asymmetric supercapacitors using the high-capacity Bi-based electromaterials as the negative electrodes.

In this study, solvothermal method was adopted to successfully prepare graphene oxide (GO) supported SnO2 nanocomposites using tin tetrachloride pentahydrate and graphene oxide as raw materials, tetra-methyl ammonium hydroxide (TMAH) as a control agent. The synthetic materials presented the efficient capacity in the photocatalytic degradation and photoelectric conversion. In the photocatalytic degradation of rhodamine B (RB) and methylene blue (MB), sample SnO2-0.1% GO showed the optimal photocatalytic efficiencies for RB (97.26%) and MB (89.43%) degradation. According to the different degradation performances of RB and MB functional groups, we reasonably explained the electron transfer mechanism at the interface of SnO2-GO nanomaterials, and verified it in the experiment of photoelectric conversion proceed combined with titanium dioxide nanotube arrays (TiO2NTs). The enhanced photocurrent density and stability can also be effectively improved due to the effective photoelectron transfer from SnO2 to GO surface.

Titanium oxide (TiO2) has been widely investigated as a photocatalytic material for degradation of organic pollutant in waste water. However, nanosized granular TiO2 nanoparticles are hard to be recycled and re-utilized in water and many cause secondary pollution of water. Hence, we constructed a foam-like photocatalyst, which was composed of carbonaceous support: activated carbon nanotube foams and Ag-doped TiO2 nanoparticles through a method of a template synthesis and carbonization strategy. The as-prepared photocatalyst evidenced to be hierarchical macroporous and mesoporous and exhibited remarkable photocatalytic performance toward the degradation of unsymmetrical dimethylhydrazine under UV and visible light. The structure characterization and photocatalytic performance investigation confirmed that the enhanced photoresponse was attributed to the high efficiency of charge separation and the surface plasmon resonance effect of metallic Ag. The adsorption synergetic effect of the hierarchical porous structure also played an important role in photodegradation. The as-prepared photocatalyst showed great potential in the treatment of waste water containing organic pollutant.

Polylactide-b-fullerene-b-poly(3-hexylthiophene) (PLA-b-C60-b-P3HT) triblock copolymer via a combination of 1,3-dipolar cycloaddition reaction and controlled ring-opening polymerization technique was successfully synthesized. The structure, morphology and crystallinity of PLA-b-C60-b-P3HT copolymer were characterized by 1H NMR, GPC, DSC, TGA, XRD, UV–vis, PL and AFM measurements. Nanoporous C60/P3HT films were easily prepared from PLA-b-C60-b-P3HT triblock copolymer by casting the copolymer followed by thermal annealing and chemical etching of the PLA chains. Fullerene molecules could self-assembly between P3HT and PLA to form a continuous film. An ordered nanoporous C60/P3HT film was formed in AFM by chemically etching the PLA microphase with NaOH solution. Photoluminescence analysis showed that the photoinduced electron transfer of the ordered nanoporous C60/P3HT film was significantly improved compared to the physically blending sample due to the increased interface between the P3HT and the C60.

Carbon microfibres (CMFs) were synthesised on SiO2 particles by catalytic chemical vapour deposition at 1200°C using ethanol as carbon precursor, iron nitrate as the catalyst precursor, and nitrogen as a carrier gas. The structure and morphology of the products were characterised by X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy and Raman spectroscopy. CMFs obtained after a deposition time of 5 h have a diameter of 5–10 μm and a length of a few hundred micrometres. In the deposition process, Fe–Si–O–C droplets were first formed on the surface of SiO2 particles, and then carbon fibres grew as a result of the catalysis of the droplets. Carbon fibres have the higher graphitic structures when the deposition process is conducted at 1200°C.

Porous carbons with large specific surface area and high structural stability are conducive to Li + diffusion and cycling performance of lithium ion batteries. In this paper, porous carbon/α-Fe 2 O 3 composites were in situ synthesized using water soluble phenolic resin as carbon precursor and environmentally benign NaCl as porogen. The interaction between the metal ions and hydroxyl groups in the resin facilitates the self-assembly of the precursors. The presence of NaCl enables the uniform dispersion of ferrous gluconate in the phenolic resin and prevents the aggregation of α-Fe 2 O 3 during the later thermal treatment. When applied as anode materials for lithium ion batteries, the porous carbon provides short diffusion pathways for Li + ions and adequate buffer space to accommodate the volume change of α-Fe 2 O 3 during the discharge/charge process, leading to a high reversible capacity of 1272 mAh g −1 at 100 mA g −1 after 200 cycles, which is much higher than that of carbon/α-Fe 2 O 3 without addition of NaCl. This strategy provides a simple and low-cost way for the mass production of novel anode materials of lithium ion batteries.

Calcium-magnesium-alumina-silicate (CMAS) attack has been regarded as one of the significant failure mechanisms for thermal barrier coatings (TBCs). In this study, CMAS corrosion behavior of BaLa 2 Ti 3 O 10 , a novel TBC material, is investigated at 1300 °C and 1350 °C for 0.5 h, 4 h, 12 h and 24 h. Results reveal that BaLa 2 Ti 3 O 10 has high resistance to molten CMAS infiltration, attributable to the formation of a dense reaction layer. X-ray diffraction, scanning electron microscope, energy dispersive spectroscope, transmission electron microscope confirm that the layer consists of apatite, celsian and perovskite phases. With increased corrosion duration, the layer retains good phase stability and the thickness increases. The formation of corrosion products and the reaction layer are discussed according to a dissolution-reprecipitation mechanism and the optical basicity theory.

In this work, Eu2O3/Au/SnO2 ternary nanofibers were prepared via a synergetic approach including electrospinning and calcination. The sensor based on Eu2O3/Au/SnO2 nanofibers exhibited a remarkable response (~65) to 100 ppm acetone at a relatively low operating temperature (200 °C), furthermore, the fast response-recovery kinetics and selective acetone detection had been observed simultaneously. The enhancement of acetone sensing properties can be attributed to the construction of Eu2O3/SnO2 heterostructures and the chemical sensitization of Au nanocatalysts, suggesting a pathway to develop high-efficient acetone sensors for health security.

Metal doping MnO2 has better electrochemical performance than pure MnO2. We have demonstrated a facile approach for synthesizing Mg-doped MnO2@ carbon cloth via a typical hydrothermal reaction. The intercalation of Mg2+ rapidly increases the operating window to 1.2 V. Compared to other metal ions (Co2+, Fe3+, Bi2+, Al3+, Cr2+) doping, Mg2+ doping further increases the lattice defects of MnO2, achieving more vacancies, and effectively improving the performance of MnO2. As a flexible symmetric solid supercapacitor (FSSSC), the voltage window can be extended to 2.2 V, and the energy density of FSSSC reaches 2.06 mW h/cm3 at 43.94 mW/cm3. The device can illuminate a 2.2 V LED successfully, showing its huge actual application value.

Ultrahigh specific capacity silicon is considered as a potential anode candidate for lithium-ion batteries (LIBs). In order to reduce the influence of the large volume expansion and poor conductivity of silicon, a few silicon nanoparticles are now used in commercial anodes, which increases costs and weakens the overall specific capacity. Here, we used low-cost aluminum–silicon alloys as raw materials to obtain porous silicon (pSi) particles by simple chemical etching. Then, Ag doped porous silicon/graphite (Ag-pSi/G) composite was prepared by depositing ultrafine Ag nanoparticles and mixing low-quality graphite. The large specific surface area, Ag nanoparticles and graphite provide multiple electron transport pathways in Ag-pSi/G, so they greatly increase the conductivity of the Ag-pSi/G and effectively reduce its volume expansion. The Ag-pSi/G composite shows high initial charging capacity (3313 mAh g−1 at 0.1 A g−1) and initial coulombic efficiency (82.2%), and stable reversible specific capacity of 770 mAh g−1 over 300 cycles at 1 A g−1. This simple and scalable preparation process provides a new thought for the broad application of micron silicon materials in the high-performance LIBs.

Recently years, hydrogels have received increased attention due to their promising applications in wound dressing, tissue engineering, biosensors and human-machine interfaces. However, designing hydrogels with good mechanical strength and self-healing ability remains a challenge. As a novel strategy, functional Janus nanosheets (JNs) were used as reinforcement to develop self-healing nanocomposite hydrogels. Herein, the silica Janus hollow spheres were prepared by a sol-gel process, modified with poly(2-(acryloyloxy)ethyl ferrocenecarboxylate)(PMAEFc)/polydopamine(PDA) to the internal/external surfaces and then crushed to fabricate the SiO2@PMAEFc/PDA JNs. The SiO2@PMAEFc/PDA JNs were then used as robust reinforcement to design self-healing nanocomposite hydrogels. Based on multiple effects of metal–coordination and host–guest interactions, the mechanical strengths and self-healing properties of hydrogels were both enhanced. Specially, after introducing JNs, the rupture stress of hydrogels increased from 1.27 MPa to 2.23 MPa, and the self-healing efficiency improved from 66.7% to 92.4%. These results demonstrate that JNs can be used as robust reinforcement to fabricate self-healing nanocomposite hydrogels, which enriches the design of self-healing hydrogels and broadens the application prospects of Janus nanomaterials.

Zinc oxide (ZnO) microstructures were successfully prepared by hydrothermal synthesis with PEG4000 at 120°C for 24 h. The crystalline phase and morphology of ZnO microstructures were characterised by X-ray diffraction and scanning electron microscopy. The results show that the rod-like, flower-like and dumbbell-shaped ZnO microstructures can be easily controlled by varying the amount of PEG4000. The photoluminescence spectra of ZnO microstructures with different morphology at room temperature show four emission peaks at about 362, 389, 421 and 487 nm. The photocatalytic activities of ZnO microstructures are evaluated by degradation of methylene blue (MB) under ultraviolet light irradiation, and the degradation rates of MB with rod-like, flower-like and dumbbell-shaped ZnO microstructures reached 94.8, 95.4 and 70.9%, respectively.

In this paper, by using a self-made hydrogen-containing polymethylhydrogensiloxane having a hydrogen content of 0.20%, a polyether of F-6 and α-olefin having a carbon chain length of even numbers in 6–18 as main raw materials, polyether and long-chain alkyl co-modified polydimethylsiloxane having different molecular structures were successfully prepared via hydrosilylation reactions. 1H-NMR, TGA, DLS, fluorescence spectroscopy and surface tension measurements were used to characterize their structures and properties. The results shows that when the molar ratio of polyether to α-olefin is 5:1, an emulsion type anti-foaming agent with polyether and long-chain alkyl co-modified polydimethylsiloxane as active ingredient was successfully prepared, it basically maintains 90% quality at 300 °C, indicating good heat resistance, and the critical micelle concentration (CMC) of polyether and long-chain alkyl co-modified polydimethylsiloxane is 8.55 mg/L. The surfactant has good dilution stability compared to other small molecule. When the hydrophilic-lipophilic balance (HLB) is equal to 10, the compound emulsifier is made of Span 80 and Tween 80, the emulsification method is a phase inversion method, and the obtained emulsion has the smallest particle size and an average particle diameter of 134.4 nm, the emulsion shows good stability and uniformity, and the particle size distribution is narrow. In summary, the polyether and long-chain alkyl co-modified polydimethylsiloxane synthesized in this work have potential applications in the fields of anti-foaming agent.

Controlling micropore size is the core for synthesizing highly efficient adsorbents for gas adsorption and separation engineering. Porous carbon prepared by traditional methods usually lacks competitiveness due to the random micropore size or complex process. Herein, we report a novel strategy for synthesizing nitrogen doped carbons nanosheets (Cu-NDPCs) with unimodal ultra-micropore based on the metal-organic covalency and the anion regulated in situ copper template. The thickness of single Cu-NDPCs is about 4.2 nm. In the presence of Cl−, the porosity of Cu-NDPCs can be tuned at 4.1–4.8 A by adjusting the pyrolysis temperature. Among them, Cu-NDPC-800 has unique carbon nanosheets networks structure, ultrahigh surface area (2150 m2 g−1), large micropore volume (0.92 cm3 g−1) and abundant surface N doping (5.33%). As an adsorbent, it exhibits superhigh C2H2, C2H6, C3H8 and CO2 uptakes (6.7, 7.0, 11.4 and 4.4 mmol g−1) and corresponding x/CH4 or CO2/N2 IAST selectivities (12.9, 17.8, 468.6, 4.3 and 17.1) under ambient conditions. Meanwhile, the Cu-NDPC-800 possesses excellent cyclic stability.

Cheap and excellent conductive substrates with large and manipulated geometric area have become an indispensable research object for non-self-supporting OER electrode materials to achieve the practical application. In this study, low-crystallinity 2D morphology iron hydrogen phosphate material (FPO3) with thickness of 12–16 nm is obtained by an easy polyol refluxing method. Its overpotential drop-casted on nickel foam (FPO3/NF) for OER is just 309 mV at the current density of 10 mA cm−2. Through the detailed comparative analysis, its number and the intrinsic activity of active sites for OER effectively enhanced because of the two-dimensional morphology, the low crystallinity, the excellent redox activity of iron, and the more beneficial synergy between NF and FPO3. Those results also indicate that using NF as the substrate is a high-efficiency method to realize the practical application of non-self-supporting electromaterials by a simple drop-casted treatment.

The development of highly efficient and robust bifunctional oxygen electrocatalysts is of great importance for optimizing the performance of rechargeable Zn-air batteries. In this study, Co Ni phosphides encapsulated in N, P co-doped carbon (CoNiP/PNC) were prepared by a simple one-step pyrolysis method. The obtained catalyst exhibited outstanding oxygen reduction and oxygen evolution reaction (ORR and OER) activities in alkaline media. It exhibited a positive half-wave potential of 0.84 V versus the reversible hydrogen electrode for ORR, as well as a low overpotential of 470 mV to achieve 10 mA cm−2 for OER, comparable with the benchmark Pt/C and IrO2 catalysts. Furthermore, the rechargeable Zn-air battery was fabricated, which showed a high specific capacity of 729.3 mAh gZn-1, a high peak power density of 171.0 mW cm−2, and good stability. It reveals that the interplay between heteroatom-doped carbon layers and Co Ni phase leads to the high ORR activity, and the in-situ formed bimetallic hydroxides/oxides contribute to the great OER performance. This work would inspire the future development of bifunctional electrocatalysts towards electrocatalysis in energy conversion and storage fields.

The Ni-based catalysts have a wide range of industrial applications due to its low cost, but its activity of CO2 methanation is not comparable to that of precious metal catalysts. In order to solve this problem, Ni-based mesoporous Ce0.8Zr0.2O2 solid solution catalysts doped with rare earth were prepared by the incipient impregnation method and directly used as catalysts for the methanation of CO2. The catalysts were characterized systematically by x-ray powder diffraction (XRD), N2 physisorption, transmission electron microscopy (TEM), energy-dispersed spectroscopy (EDS) mapping, x-ray photoelectron spectroscopy (XPS), H2 temperature programmed reduction (H2-TPR), CO2 temperature programmed desorption (CO2-TPD), and so on. The results show that Ni is highly dispersed in the mesoporous skeleton, forming a strong metal–skeleton interaction. Therefore, under the condition of CO2 methanation, the hot sintering of metallic Ni nanoparticles can be effectively inhibited so that these mesoporous catalysts have good stability without obvious deactivation. The rare earth doping can significantly increase the surface alkalinity of catalyst and enhance the chemisorption of CO2. In addition, the rare earth elements also act as electron modifiers to help activate CO2 molecules. Therefore, the rare earth doped Ni-based mesoporous Ce0.8Zr0.2O2 solid solution catalysts are expected to be an efficient catalyst for the methanation of CO2 at low-temperature.

The temperature and pH dual-responsive polyhedral oligomeric silsesquioxane/poly[2-(dimethylamino)-ethyl methacrylate]-b-poly(N-isopropylacrylamide) hybrid materials (POSS/PDMAEMA-b-PNIPAM) were synthesized via combination of thiol-ene click chemistry and reversible addition fragmentation chain transfer polymerization. Their structures and self-assembly behaviors were characterized via 1H NMR, TEM, UV–vis and DLS measurements. POSS/PDMAEMA-b-PNIPAM could self-assemble into thermo- and pH-sensitive micelles with the POSS heads forming as a core and the PDMAEMA-b-PNIPAM chains as a corona. In vitro drug release behavior of POSS/PDMAEMA-b-PNIPAM micelles loading camptothecin indicated that the rate of drug release could be effectively controlled by altering the temperature and pH values of the environment. As 80% of the camptothecin drug was released at pH 5.5 or temperature of 45 °C within 35 h, the excellent thermo- and pH-response ability of POSS/PDMAME-b-PNIPAM micelles makes them desirable candidates for controlled drug delivery systems.

Carbon/graphite carbon nitride (C/CN-T-x) hybrid composites with high photocatalytic activities under visible light irradiation were synthesized by an in-situ hard template method using the partially formaldehyde-modified dicyandiamide (PFMD) and tetraethyl orthosilicate (TEOS) as the precursors and template, respectively. The structures of the as-prepared composites were characterized by thermogravimetric analysis (TGA), X-ray diffraction (XRD), elemental analysis, nitrogen adsorption-desorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM), photoluminescence (PL) spectroscopy, and X-ray photoelectron spectroscopy (XPS). The composite prepared under the optimal conditions exhibits the large surface area of 174 m2･g−1 and high photocatalytic activity for the degradation of methylene blue (MB) under visible light irradiation. The significant improvement in photocatalytic activity of the composite, as compared with the pure graphite carbon nitride (CN), is attributed to the large surface area, strong dye adsorption ability and enhanced separation efficiency of photogenerated electron-hole pairs.

MnO2 nanosheets were prepared by hydrothermal deposition method, and supported on biomass-derived crosslinked carbon nanosheets to form a composite material (MnO2@R). First, rambutan peels were synthesized into porous carbon by pyrolysis and activation, and then MnO2 was fixed on the carbon nanosheets by hydrothermal deposition method. The MnO2@R composite material and nitrogen-doped porous carbon were assembled into an asymmetric supercapacitor. Among them, MnO2@R composite material and nitrogen-doped rambutan peel-derived porous carbon were used as positive electrode and negative electrode. Moreover, the asymmetric supercapacitor has excellent cycle stability. After 5000 cycles under 0.5 A g−1, its capacitance loss is only 12%. The asymmetric supercapacitors found in these studies have excellent energy and power density characteristics, which opens up application prospects for biomass carbon-derived composite materials.

Carbon cloth (CC) is proved to be a very promising supercapacitor substrate due to its flexibility and excellent mechanical properties. In this paper, a simple and environmentally friendly hydrothermal reaction was used to construct petal-shaped Ni-doped MnO2 nano-array electrode material based on a flexible CC with strong adhesion, and PVA/Na2SO4 gel electrolyte was coordinated to assemble flexible quasi-solid-state supercapacitor. Electrochemical tests manifested that the voltage window of Ni-doped MnO2 nano-array@CC electrode materials could reach 1.2 V, especially the area specific capacitance was up to 1398.8 mF cm−2 As an assembled device,the voltage window could reach 2.2 V, the volumetric capacitance was as high as 1022.08 mF cm−3, the energy density could reach 0.6871 mWh·cm−3, and the power density could be achieved as 31.43 mW cm−3, demonstrating good prospect in applications for flexible energy storage device.

Nearly inexhaustible sodium sources on earth make sodium ion batteries (SIBs) the best candidate for large-scale energy storage. However, the main obstacles faced by SIBs are the low rate performance and poor cycle stability caused by the large size of Na+ ions. Herein, a universal strategy for synthesizing amorphous metals encapsulated into amorphous B, N co-doped carbon (a-M@a-BCN; M = Co, Ni, Mn) nanotubes by metal cation-assisted carbonization is explored. The methodology allows tailoring the structures (e.g., length, wall thickness, and metals doping) of a-M@a-BCN nannotubes at the molecular level. Furthermore, the amorphous metal sulfide encapsulated into a-BCN (a-MSx @a-BCN; MSx : CoS, Ni3 S2 , MnS) nanotubes are obtained by one-step sulfidation process. The a-M@a-BCN and a-MSx @a-BCN possess the larger interlayer spacing (0.40 nm) amorphous carbon nanotube rich in heteroatoms active sites, making them exhibit excellent Na+ ions diffusion kinetics and capacitive storage behavior. As SIBs anodes, they show high capacity, excellent rate performance, and long cycle stability.

Janus nanomaterials can be highlighted to design a series of smart materials with the remarkable characteristic of two different properties or constituents. In this manuscript, functional Janus graphene oxide-type (GO-type) nanomaterials were fabricated by Pickering emulsion template and successfully applied to develop of dual self-healing nanocomposite hydrogels. Asymmetric functionalization of Janus nanosheets were achieved in typical oil-in-water Pickering emulsion by atom transfer radical polymerization (ATRP) and mussel-inspired chemistry. Poly(2-(acryloyloxy)ethyl ferrocenecarboxylate) (PMAEFc) and polydopamine (PDA) were unsymmetrically grafted on the two sides of GO (Janus GO-PMAEF/PDA (JGNs)), which successfully applied in self-healing nanocomposite hydrogels. The collaborative effect of metal-ligand coordination and host-guest interaction make the dual self-healing hydrogels have excellent self-healing properties (self-healing efficiency can reach to 93.4% within 1 h) and mechanical strength (tensile strength of 0.94 MPa and strain of 508.5%). Therefore, these chemical asymmetric JGNs have outstandingly application prospect in the development of smart materials.

In the alkaline system, the mechanism relationships of the transition metal phosphate materials between pseudocapacitors and OER are analyzed, more active sites, excellent conductivity and enhanced intrinsic activity are important factors in enhancing their OER and capacitance performances. In this study, the capacitance of synthesized Co7(PO4)2(HPO4)4 after ultrasonic treatment with N-methyl-pyrrolidinone (NMP) improved 20.1 % (345 F g−1 at 1 A g−1), the overpotential for OER reduced 20 mV (293 mV at 10 mA cm−2). Based on detailed characterization analysis, ultrasonic treatment with NMP does not destroy the phases and the surface phosphate groups of the materials, but reduce the overall particle size, improve the pore volume and create some new interfaces originally located inside the material. These changes bring increased active sites, reduced internal resistance, enhanced charge transfer capability and improved intrinsic activity to the synthesized Co7(PO4)2(HPO4)4, enhancing its OER and capacitance efficiency. Additionally, the ultrasonic treatment can achieve those changes, which is most likely achieved by sacrificing some mesopores with small diameters, it also provides a simple and convenient method for enhancing the performance of other three-dimensional mesoporous materials.

Low-temperature phase change material (PCM) is a material that stores additional heat at elevated temperatures and releases energy when the temperature is below the limit. A way to solve the low-temperature disaster of asphalt pavement is desired to be developed. In this article, a two-component organic low-temperature PCM was encapsulated by melamine-urea-formaldehyde resin and finally reinforced with polypropylene. The reinforced PCM microcapsules were mixed with 70# SBS (Styrene-Butadiene-Styrene) modified asphalt in SMA-10 (Stone Matrix Asphalt-10) to form aggregates. The results showed that after adding 6.0% (w/w) reinforced PCM microcapsules, there was a significant delay compared to a blank sample with a maximum temperature difference of 1.8 °C when the temperature dropped to 0 °C, which proved that this method has a good potential in resisting low-temperature disasters on asphalt pavement and deserves further improvement.

Asphalt pavement cracks easily in low-temperature environments. In order to address the problem, phase-change material (PCM) microcapsules working at 0–10°C are used to replace some of the ...

In practical engineering, sand fills or deposits are often under an anisotropic stress condition. Thus, these soil elements sustain an initial static shear stress before being acted upon by...

A new polymer namely poly (N-(3-aminopropyl) methacrylamide)-b-poly(N-isopropylacrylamide) (PAPMA-b-PNIPAM) was made for pH-triggered drug delivery by means of aqueous reversible addition-fragmentation chain transfer (RAFT) polymerization. PAPMA-b-PNIPAM was hydrophilic at 25 °C, and micelles were formed at 39 °C. The PAPMA chain was crosslinked with terephthaldicarboxaldehyde at pH = 9.0 and shell cross-linking (SCL) micelles were prepared. The sizes of the SCL micelles were 45~65 nm which can be reversible dissociated under acidic conditions. The formation of temperature-responsive SCL micelles and their cleavage behaviours were characterized.

Sn/carbon nanofibers with well dispersed Sn nanoparticles embedded in carbon nanofibers were fabricated by an electrospinning process. A SnO2 sol was used as the Sn precursor in order to improve the compatibility of tin/carbon composites and prevent Sn nanoparticles from severe agglomeration upon thermal treatment. When evaluated as a binder-free anode for lithium ion batteries, the Sn/carbon nanofibers deliver a high specific capacity of 583 mA h g−1 after 100 cycles and good cycling performance with coulombic efficiency up to 99%. The high lithium storage capability is mainly attributed to the optimized structure features including the well dispersed tin nanoparticles, high porosity, and the cushion effect of the carbon nanofibers.

Carbon-supported SnO2 nanowire arrays were synthesized by a facile strategy using self-assembled mesoporous carbon as template followed by partial removal of the carbon. The as-obtained materials were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and nitrogen adsorption. The resulting products possess a large specific surface area due to the free interspaces between the nanowires. When evaluated as anode materials for lithium-ion batteries, the carbon-supported SnO2 nanowires can deliver large reversible capabilities with excellent cycling performance on account of the mesoporous carbon matrix, which can be served as a buffering layer to relax the stress, reduce the volume variation, and protect the SnO2 nanowires from severe structural degradation during the insertion-deinsertion process of lithium ions.

The experimental study and an optimized formulation heat-reflective coating has been studied with epoxy resin as the matrix resin and nano titanium dioxide (TiO2) as the functional filler for asphalt pavement to deal with high-temperature diseases and carbon monoxide (CO) and hydrocarbon (HC) emissions from automobile exhaust. The mass ratio of the epoxy resin: diluent: curing agent: nano-TiO2: and ferric oxide was determined to be 100: 24: 36: 6.4: 0.3. Under the irradiation of the tungsten–iodine lamp, the epoxy coatings can reduce the surface temperature of the asphalt pavement to 57.9°C, whereas the reference surface temperature reaches 71.3°C. The epoxy coatings exhibited excellent wear resistance after 3 h of testing on a rutting machine. Furthermore, the CO/HC decomposition effect on the epoxy coatings has also been investigated, with a maximum decomposition rate of 19.3 % at 50°C and an ultraviolet intensity of 2,770 μW/cm2. The epoxy coatings have been proven to be a good solution for high-temperature disease and excessive CO/HC emissions from asphalt pavements.

Mesoporous SnO2 nanotubes are prepared by templating against carbon fibers through a facile solution approach followed by calcination at 800 °C for 2 h. The nanotubes are characterized by means of scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and nitrogen adsorption. The electrochemical performances as the anodes of lithium-ions batteries are studied by the cyclic voltammogram (CV) and galvanostatic discharge–charge voltage tests. Because of its unique structure (the mesoporous wall, internal void and open ends), the as-obtained mesoporous SnO2 nanotubes demonstrate a reversible capacity of 585 mA h g−1 up to 50 cycles at a high current density of 400 mA g−1.