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Herein, two‐dimensional (2D) carbon nanosheets derived from biomass precursor is successfully synthesized via a cost‐effective salt‐templated process. Microstructural characterization and Raman spectral analysis of the sample derived from the salt template method reveals the formation of carbon nanosheets. The nanosheet thickness and its capacitance have been altered by varying the carbon precursor to salt‐template ratio. From the AFM data, the thickness of the as‐prepared thin carbon sheet was measured as ~5.16 nm, and the other thicker carbon sheet thickness was determined to be between 24 and 38 nm. The Brunauer Emmett Teller (BET) analysis shows that the thinner nanosheets possess a high specific surface area (SSA) of 485 m2 g−1, with slit‐pore geometry having a total pore volume of 0.29 cm3 g−1. Hence, compared to thicker carbon nanosheets (63.6 F g−1), the thinner carbon nanosheets exhibit superior electrochemical capacitance of 146 F g−1 in an aqueous 6 M KOH electrolyte, without employing any chemical activation. The electrochemical series resistance of as‐prepared carbon nanosheet samples was found to be <1 Ω with charge transfer resistances in the range of 0.29 Ω (thicker sheets) to 0.18 Ω (thinner sheets). The specific capacitance and electrochemical properties vary significantly when the nanosheet thickness has been tuned from thicker to thinner by altering the starch ratio in NaCl. The two‐electrode cell assembled using thinner carbon nanosheets exhibited the capacitance of 70.1 F g−1 with energy and power densities as 9.7 Wh kg−1 and 20 kW kg−1 respectively. [ABSTRACT FROM AUTHOR]

ABSTRACT: Metal dots-nitrogen-carbon catalysts have become a hot topic in recent years because of special coordination environment. Herein, for the study the W nanodots and nitrogen co-decorated carbon skeleton (W@NC) was prepared for hydrogen evolution reaction (HER). In particular, NaCl templates not only restrict the growth of nanodots, but also improve the purity of phase. By optimizing the feeding ratio of ammonium metatungstate, W nanodots (the size is about 1.2 ± 0.6 nm) dispersed well on N-doped C skeleton, and this special structure could effectively promote electron transfer and ion diffusion during HER process. As a result, the optimized W@NC hybrids exhibited excellent HER performance in alkaline media with a rather low over-potential (228 mV at 10 mA cm–2) and outstanding durability over 10 h.

Capacitive Deionization (CDI) is an electrochemical desalination technique based on the electrical double layer, which accumulate salts from the water stream; however, achieving higher salt adsorption for low-concentration salt is hindered due to several obstacles, such as low adsorption capacity and slow kinetics on the electrode surface. In this study, we reported a novel electrode fabrication method designed to enhance the hydrophilicity of the electrode material and activate hierarchical porosity, making a more accessible adsorption surface area. This modification enables more than 210 % improvement in salt adsorption capacity, achieving 17.5 mg g-1 in a single pass process with good stability in an 850 mg/L NaCl solution at 1.2 V, surpassing most reported carbon-based electrodes under similar operating conditions. Electrode formulation consists of Nitrogen (N) and Phosphorus (P) doped hierarchical carbon nanotubes (CNTs) network blended with additional NaCl as a green and removable template to reach higher levels of porosity. The electrochemical sorption behavior of the sample was characterized over a voltage range of –0.5 to 0.7 V. Furthermore, the electrode materials were characterized utilizing various characterization methods, including Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), X-ray Diffraction (XRD), Raman Spectroscopy, Fourier Transformed Infrared (FTIR), X-ray Photoelectron Spectroscopy (XPS), and Brunauer-Emmett-Teller (BET) to explore the correlation between microstructure, morphology, and properties. Our finding reveals that not only N and P can affect adsorption, but also the novel cathode preparation method, which employs a removable NaCl templated hierarchical porous electrode, has a profound effect on the electrochemical and CDI results. This finding will open a new perspective in designing electrodes for all electrochemical systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • NaCl nanocrystals were used as a template for the synthesis of few layer MoS 2. • Sodium is able to promote the formation of in-plane sulfur defects. • The catalyst evolution throughout the induction period was studied in detail. • Sodium-assisted sulfur vacancies lower the energy barrier of the carboxylate route. The effective conversion of CO 2 to methanol utilizing green hydrogen under moderate conditions represents a promising approach for achieving carbon neutrality. MoS 2 demonstrates exceptional catalytic performance at temperatures below 200 °C, however, generating in-plane sulfur defects is challenging due to the intact planar structure. Introducing heteroatoms to induce sulfur vacancy formation and modulate their chemical environment remains a significant obstacle. In this study, we developed a NaCl-assisted method for synthesizing MoS 2 and discovered that a small quantity of sodium not only promotes the formation of sulfur vacancies during the induction period, but also encourages CO 2 hydrogenation via the carboxylate route, as opposed to the CO 2 dissociation to CO* route over non-modified sulfur vacancies. Furthermore, catalysts at various stages throughout the 60 h induction period were characterized, revealing that the increase in sulfur vacancies and enhanced H 2 dissociation capability are primary factors contributing to improved methanol yield. The sodium-modified MoS 2 achieves a methanol space–time yield of up to 571 mg MeOH g cat. −1 h−1 at 200 °C and 5 MPa with a 4.8% CO 2 conversion and 96% methanol selectivity. The turnover frequency based on total sulfur vacancies reaches 170 h−1. This research is anticipated to offer a new strategy for enhancing the catalytic performance of CO 2 hydrogenation to methanol using heteroatom-assisted defect engineering. [ABSTRACT FROM AUTHOR]

The rational design of cost-effective and highly efficient catalysts for the oxygen evolution reaction (OER) is vastly desirable for advanced renewable energy conversion and storage systems. Tailoring the composition and architecture of electrocatalysts is a reliable approach for improving their catalytic performance. Herein, we developed hierarchical ultra-thin Co nanosheets coupled with N-doped carbon plate (Co-NS@NCP) as an efficient OER catalyst through a feasible and easily scalable NaCl template method. The rapid dissolution-recrystallization-carbonization synthesis process allows Co nanosheets to self-assemble into plenty of secondary building units and to distribute uniformly on N-doped carbon plate. Benefitting from the vertically aligned Co nanosheet arrays and hierarchical architecture, the obtained Co-NS@NCP possess an extremely high specific surface area up to 446.49 m2 g−1, which provides sufficient exposed active sites, excellent structure stability, and multidimensional mass transfer channels. Thus, the Co-NS@NCP affords remarkable electrocatalytic performance for OER in an alkaline medium with a low overpotential of only 278 mV at 10 mA cm−2, a small Tafel slope, as well as robust electrocatalytic stability for long-term electrolysis operation. The present findings here emphasize a rational and promising perspective for designing high-efficiency non-precious electrocatalysts for the OER process and sustainable energy storage and conversion system.

As a thermosetting resin with excellent properties, epoxy resin is used in many areas such as electronics, transportation, aerospace, and other fields. However, its relatively low thermal conductivity limits its wide application in more demanding fields. Here, a three-dimensional carbon (3DC) network was prepared through NaCl template-assisted in situ chemical vapor deposition (CVD) and used to reinforce epoxy resin for enhancing its thermal conductivity. The 3DC was prepared with a molar ratio of sodium atom to carbon atom of 100:20, and argon atmosphere in CVD led to an optimal improvement in the thermal conductivity of epoxy resin. The thermal conductivity of epoxy resin increased by 18% when the filling content was 3 wt.% of 3DC network because of the high contact area, uniform dispersion, and enhanced formation of conductive paths with epoxy resin. As the amount of 3DC addition increases, the thermal conductivity of composites also increases. As an innovative exploration, the work presented in this paper is of great significance for the thermal conductivity application of epoxy resin in the future. [ABSTRACT FROM AUTHOR]

Graphite foams were prepared using foaming method and template method with nature flake graphite powder as main raw materials, sucrose as a foaming agent or binder, as well sodium chloride as a template. The compositions, microstructure, thermal properties and mechanical performance of the fabricated graphite foams were investigated by X-ray fluorescence spectrometer, scanning electron microscope, laser thermal conductivity meter, and electronic universal testing machine, respectively. The results show that water in binder played an important role in forming process of graphite foams. Graphite foams with controllable pore structure can be obtained by template method. The porosity of graphite foams increased with increasing the concentration of templating agent. With a fixed concentration of the templating agent the thermal diffusivity of the foams deceased with increasing the concentration of binder. Moreover, the obtained graphite foams has a minimum density of 288 kg/m3, a maximum porosity of 78% and a maximum thermal diffusivity of 7.14 × 10−6 m2/s. Two binding models of graphite foams prepared using template method has been proposed in the first time. This work provided an optimized processing for graphite foams with simple preparation, low-cost recyclable raw materials, and a promising thermal management material for many applications. Image 1 • New type of graphite foams were developed using natural flake graphite as main raw material. • Two binding models of graphite foams prepared using template method has been proposed. • Water can promote the pore-forming during the forming process of graphite foams. • The routes have superiority of simple, low-cost with recyclable raw materials. [ABSTRACT FROM AUTHOR]

• The porous PDMS (P-PDMS) film was fabricated by NaCl template method. • The P-PDMS film achieved an average 18.7 ℃ lower than the sub-ambient. • The P-PDMS film has a water contact angle of 132.92°. Passive daytime radiative cooling (PDRC) is a green and energy-free passive cooling method by reflecting sunlight and radiating heat into the cold outer space through atmospheric transparent windows (ATW). High reflectivity and high emissivity are two vital factors affecting the cooling performance. In this work, an environmentally friendly porous polydimethylsiloxanes (PDMS) radiative cooling film was fabricated, which has 73.3 % solar reflectance (0.3–2.5 μm) and 99.7 % infrared emissivity (8–13) μm. Thus, the sample displayed a remarkable PDRC property by yielding an average temperature drop of 18.7 ℃ compared to the sub-ambient temperature at the solar intensity of 769 W/m2. At the same time, the film with hydrophobicity (132.92°) can decrease pollution caused by dust, which is significant for prolonging life and maintaining the performance of these films. This technique is simple and economical, and has the prospect of large-scale commercial application. [ABSTRACT FROM AUTHOR]

The sub-10 nm metal-based nanomaterials (SMNs) show great potential for the electrochemical energy storage field. However, their ion storage capacity and stability suffer from severe agglomeration and interface problems. Herein, a universal strategy is reported to synthesize a wide range of SMNs (e.g., metal, nitride, oxide, and sulfides) embedded in free-standing carbon foam (SMN/FC-F) composite electrodes by crossing the interfacial confinement of NaCl self-assembly with the thermal-mechanical coupling of powder metallurgy. The pressure-enhanced NaCl self-assembly interfacial confinement is greatly beneficial to preventing SMN agglomeration and promoting SMNs embedded in FC-F which originate from the welding of carbon nanosheets. They are confirmed via a series of advanced characterizations including X-ray photoelectron spectroscopy, and spherical aberration-corrected scanning transmission electron microscopy, with theoretical computations. Benefiting from the unique structure, SMNs/FC-F delivers ultrafast and stable ion-storage kinetics. As a proof-of-concept demonstration, the MoS 2 /FC-F shows excellent ion storage kinetics and superior long-term cycling performance for ion storage (e.g., Na 3 V 2 (PO 4 ) 2 O 2 F/C//MoS 2 /FC-F sodium-ion batteries exhibit a high reversible capacity of 185 mAh g -1 at 0.5 A g -1 with a decay rate of 0.05% per cycle.). This work provides a new opportunity to design and fabricate promising SMN-based free-standing working electrodes for electrochemical energy storage and conversion applications., (© 2023 Wiley-VCH GmbH.)

Vanadium trioxide material have attracted enormous attention recently, owing to their high theoretical capacity for use as anodes in lithium ion batteries. However, the unstable structure of V 2 O 3 limits its practical application. It is challenge to develop a simple, scalable and economical technique to produce 3D porous carbon-based V 2 O 3 materials with high structure stability. In this work, a facile NaCl template-assisted freeze-drying strategy was used to produce 3D porous carbon-encapsulated V 2 O 3 (3D porous V 2 O 3 @C) composites with highly crystalline architecture, uniformly carbon-encapsulated V 2 O 3 nanoparticles and interconnected conductive carbon networks. The resultant 3D porous V 2 O 3 @C anode exhibits significantly enhanced rate performance (797 mAh/g at 0.1 A/g, 715 mAh/g at 0.3 A/g, 658 mAh/g at 0.5 A/g, 598 mAh/g at 1 A/g, 480 mAh/g at 3 A/g and 426 mAh/g at 5 A/g) and long-term cycling stability (506 mAh/g at 5A/g after 2000 cycles). The present work suggests a scalable preparation of the 3D porous carbon-based V 2 O 3 materials, which may be extended to preparing other 3D porous materials for potential applications in energy storage, catalysis and sensors. [ABSTRACT FROM AUTHOR]

Abstract Hierarchical porous carbon (HPC) materials have been synthesized via a combined freeze drying and carbonization process, that using egg white protein (EW-protein) as a precursor, NaCl as a template. Two competitive effects, salting out and salting in of EW-protein, were conveniently tuned by changing the NaCl concentrations, resulting in controllable hierarchical structures, surface areas and pore size distributions of HPC. The optimal product of HPC-4 displays a 3D honeycomb-like network (100–200 nm), inner cubic mesopores (20–50 nm) and high large surface area of 1745.64 m2 g−1. As an anode material of Li-ion battery, HPC-4 presents reversible capacity of 1131 mAh g−1 after 100 cycles at 0.2 A g−1, good rate capability, and a reversible capacity of 553 mA h g−1 after 1000 cycles at high current density of 10 A g−1. This work provides an environmentally friendly and low cost route to fabricate HPC with excellent electrochemical performances. Graphical abstract Image 1 Highlights • EW-protein derived N-doped HPC by using NaCl as template. • Salting in and salting out of protein affect the pore structures of HPC. • HPC exhibits good electrochemical performance. • It's an environmentally friendly and low cost route to fabricate HPC. [ABSTRACT FROM AUTHOR]

The reasonable design of atomically dispersed Ni-N x sites in porous carbon nanostructures is an efficient strategy to enhance the electrochemical CO 2 reduction reaction (CO 2 RR) catalytic activity. In this work, atomically dispersed Ni-N x sites on hierarchically porous carbon catalysts (HP-Ni-NC) were fabricated by a facile NaCl template-assisted pyrolysis method. The catalysts exhibit a large specific surface area and a hierarchical porous structure, facilitating the exposure of numerous active sites and the mass/electron transport during the CO 2 RR. Consequently, the CO Faradaic efficiency maintained over 90% in a wide potential window on the optimized HP-Ni-NC-2 catalyst. The CO partial current achieved 15.2 mA cm -2 at -0.9 V (vs reversible hydrogen electrode) in a H-cell. Furthermore, the current density can achieve 250 mA cm -2 at a cell voltage of 3.11 V in a membrane electrode assembly electrolyzer, demonstrating great promise for commercial-scale application. This study presents a facile approach to synthesizing hierarchically porous structure single-atom catalysts with superior catalytic performance toward CO 2 RR.

A cost-effective two-step approach is developed to synthesize carbon well-coated Co 9 S 8 nanoparticles (Co 9 S 8 /C-T), using NaCl as template to prepare Co/C precursor and then sulfureting. The as-obtained sample exhibits much higher lithiation ability as anode than the sample Co 9 S 8 /C synthesized without NaCl template, including higher initial coulombic efficiency (83.0% with an initial discharge capacity of 799 mAh g −1 ), higher stability (709 mAh g −1 after 150 cycles at 0.2 A g −1 ) and better rate performance (362 mAh g −1 at 5 A g −1 ). [ABSTRACT FROM AUTHOR]

Sodium-ion batteries (SIBs) have a promising application prospect for energy storage systems due to the abundant resource. Amorphous carbon with high electronic conductivity and high surface area is likely to be the most promising anode material for SIBs. However, the rate capability of amorphous carbon in SIBs is still a big challenge because of the sluggish kinetics of Na+ ions. Herein, a three-dimensional amorphous carbon (3DAC) with controlled porous and disordered structures is synthesized via a facile NaCl template-assisted method. Combination of open porous structures of 3DAC, the increased disordered structures can not only facilitate the diffusion of Na+ ions but also enhance the reversible capacity of Na storage. When applied as anode materials for SIBs, 3DAC exhibits excellent rate capability (66 mA h g-1 at 9.6 A g-1) and high reversible capacity (280 mA h g-1 at a low current density of 0.03 A g-1). Moreover, the controlled porous structures by the NaCl template method provide an appropriate specific surface area, which contributes to a relatively high initial Coulombic efficiency of 75%. Additionally, the high-rate 3DAC material is prepared via a green approach originating from low-cost pitch and NaCl template, demonstrating an appealing development of carbon anode materials for SIBs. [ABSTRACT FROM AUTHOR]

Recently, Zn-based alloys are attracting intensive interest as biodegradable biomaterials. Their moderate degradation rate makes them a better potential candidate for porous scaffolds than Mg-based alloys. In this study, hot press sintering (HPS) was employed to enhance the stacking density of NaCl templates. And then, pure Zn and Zn-3 wt%Cu scaffolds with different porosities were achieved by replicating the architecture of NaCl templates. The pore structure, compressive properties and degradation behavior of the scaffolds were investigated. The scaffolds with a higher porosity of about 75% showed enhanced interconnectivity and reduced surface area due to the formation of more interconnected pores and the enlarged size of them. The scaffolds with a lower porosity of about 68% exhibited higher yield strength on account of the earlier closure of the smaller interconnected pores during deformation. The corrosion rate was decreased with the increase of the porosity due to the reduction of specific surface area. The compressive properties (including yield strength and modulus) and corrosion rate of the Zn scaffolds were significantly enhanced by the addition of 3 wt% Cu because of the solution of Cu in Zn matrix and the precipitation of CuZn 5 secondary phase. Moreover, the effect of porosity on corrosion was more distinguishable for Zn-3 wt%Cu scaffolds than pure Zn scaffolds due to the acceleration of galvanic corrosion effect. [ABSTRACT FROM AUTHOR]

Abstract: Sodium‐ion batteries (SIBs) have a promising application prospect for energy storage systems due to the abundant resource. Amorphous carbon with high electronic conductivity and high surface area is likely to be the most promising anode material for SIBs. However, the rate capability of amorphous carbon in SIBs is still a big challenge because of the sluggish kinetics of Na+ ions. Herein, a three‐dimensional amorphous carbon (3DAC) with controlled porous and disordered structures is synthesized via a facile NaCl template‐assisted method. Combination of open porous structures of 3DAC, the increased disordered structures can not only facilitate the diffusion of Na+ ions but also enhance the reversible capacity of Na storage. When applied as anode materials for SIBs, 3DAC exhibits excellent rate capability (66 mA h g−1 at 9.6 A g−1) and high reversible capacity (280 mA h g−1 at a low current density of 0.03 A g−1). Moreover, the controlled porous structures by the NaCl template method provide an appropriate specific surface area, which contributes to a relatively high initial Coulombic efficiency of 75%. Additionally, the high‐rate 3DAC material is prepared via a green approach originating from low‐cost pitch and NaCl template, demonstrating an appealing development of carbon anode materials for SIBs. [ABSTRACT FROM AUTHOR]

Mg-based scaffolds have great potential of application for bone defect repair due to their biodegradability and the excellent osteoinductivity, yet currently the fabrication of Mg-based porous materials is still a challenge. In this study, a new fabrication method was proposed to produce porous Mg scaffolds, which could be achieved by three steps: (1) defectless NaCl open porous template with enhanced relative density was prepared with NaCl particles by hot press sintering (HPS) process; (2) green compact of Mg and the NaCl template was produced by infiltration casting; (3) open porous Mg scaffold was achieved after leaching out the template. By using spherical NaCl particles and irregular polyhedral NaCl particles, respectively, two different types of templates were prepared, and correspondingly Mg scaffolds with spherical and irregular pores were respectively fabricated. The irregular-pore scaffold (I-scaffold) exhibited higher yield strength, while the spherical-pore scaffold (S-scaffold) showed superior interconnectivity and more stable compressive deformability due to the uniform spatial structure. [ABSTRACT FROM AUTHOR]

A novel, facile and scalable process of simultaneous activation and templating is developed for in situ synthesis of graphene-enhanced 3D hierarchical porous carbon nanobelt networks uniformly anchored with polycrystalline Fe 3 O 4 nanoparticles (5–45 nm) (Fe 3 O 4 –rGO/poly(vinyl alcohol) (PVA)-derived carbon) as a high-performance supercapacitor electrode. During the synthesis, 3D self-assembled NaCl particles are adopted as a structural template to direct the growth of 3D carbon nanobelt networks with interconnected macropores, KOH is used as an activating reagent to generate porous nanobelts with masses of micro-, meso- and macropores, and graphene sheets behave as a chemical activator to promote the growth of hierarchical porous thin nanobelts. The resulting Fe 3 O 4 –rGO/PVA-derived carbon electrode leads to a combination of the redox pseudo-capacitance of Fe 3 O 4 and the electric double-layer capacitance of the carbon species with a remarkably high capacitivity (538.8 F g −1 at 5 A g −1 ) and outstanding cycle performance (∼590 F g −1 after 5000 cycles at 5 A g −1 ). This work offers a new strategy for preparation of 3D hierarchical porous carbon networks for future applications. [ABSTRACT FROM AUTHOR]

Food-waste-derived biochar structures obtained through pyrolysis and with different NaCl concentrations were investigated. Increased NaCl concentration in the samples inhibited cellulose and lignin decomposition, ultimately increasing the biochar yield by 2.7% for 20%-NaCl concentration. NaCl added in solution state exhibited templating effects, with maximum increases in the Brunauer–Emmett–Teller (BET) surface area and pore volume of 1.23 to 3.50 m2∙g−1 and 0.002 to 0.007 cm3∙g−1, respectively, after washing. Adding a high concentration (20%) of NaCl reduced the BET surface area. In contrast, the mean pore diameter increased owing to the increased NaCl clustering area. Increased NaCl clustering with increased added NaCl was shown to have positive effects on NaCl removal by washing. Furthermore, as the NaCl adhered to the KCl scattered in the food waste, a high NaCl concentration also had positive effects on KCl removal. This study reports on an investigation on the effects of varying NaCl concentrations injected in solution form on the structure of food-waste biochar during pyrolysis. The templating effect was considered using both added NaCl and NaCl already contained in the food waste, with implementation of a desalination process essential for food-waste treatment for recycling.

• A one-step chemical vapor deposition method was used to synthesize spinel MFe 2 O 4 (M = Zn, Ni, Cu, Co and Mn). • NaCl and dextrin were used as porogens and structural support to synthesize a multi-cavities structure. • The gas-sensing properties of MFe 2 O 4 to organic and inorganic gases were studied by replacing Fe with transition metals. [Display omitted] In this study, a one-step chemical vapor deposition (CVD) method was used, utilizing template NaCl and dextrin as the porogen and structural support. The synthesized spinel MFe 2 O 4 (M = Zn, Ni, Cu, Co and Mn) microspheres with multiple cavities structure were applied to the acetone gas sensor detection. Through the characterization of the sensitive materials, the average pore diameter of the microspheres was about 60 nm. Compare with other metal cations, when M = Zn or Ni, the MFe 2 O 4 samples revealed the super gas sensitivity at working temperatures of 250 °C and 175 °C, and the response values to 100 ppm acetone were 25 and 24.3, respectively. In addition, they also exhibited excellent selectivity and long-term stability to acetone. The excellent gas sensitivity of ZnFe 2 O 4 and NiFe 2 O 4 could be attributed to the replacement of Fe with Zn and Ni ions to obtain a higher Fe3+/Fe2+ atomic ratio, thereby increasing the content of adsorbed oxygen. In summary, the gas sensing performance of spinel MFe 2 O 4 oxide had been systematically studied by replacing Fe with other transition metals. The iron-containing spinel oxides are expected to be promising sensing material for gas sensors due to their rich elements and excellent activity. [ABSTRACT FROM AUTHOR]

A novel type of oxygen-enriched three-dimensional porous carbons (3DPCs) is prepared using coal tar pitch (CTP) oxidized by KMnO 4 as raw material and NaCl as a green template. Oxygen-containing functional groups are grafted on the edge of polycyclic aromatic hydrocarbons (PAHs) through oxidative modification, which avoids excessive accumulation of PAHs and successfully achieves oxygen doping to provide additional pseudo-capacitance. The existence of NaCl supports the formation of 3D structure and improves the diffusion/transport capacity of electrolyte ions. The as-prepared 3DPCs show interconnected 3D structure with large effective specific surface area (3067 m2 g−1) and high oxygen content (up to 9.8%). In addition, the electric double layer capacitor assembled by 3DPC-3 exhibits the largest specific capacitance (306 F g−1 at 0.5 A g−1) and superior cycling stability (specific capacitance retention of 99.7% after 10000 cycles) in 6 M KOH electrolyte. Meanwhile, high energy density (36.8 Wh kg−1) is obtained when it is applied to EMIMBF 4 electrolyte. Overall, this work provides an effective way for the synthesis of 3DPCs and can be also conducive to the development of the high value-added CTP-based carbon material industry. • Coal tar pitch was oxidized by KMnO 4. • Oxygen-enriched three-dimensional porous carbons was prepared. • Outstanding cycling performance up to 99.7% after 10000 cycles. • High energy density (36.8 Wh kg−1) in EMIMBF 4 electrolyte. [ABSTRACT FROM AUTHOR]

Simple and reliable mass production of platinum-based alloy catalysts with excellent activity and stability is an enormous challenge for the wide commercialization of proton-exchange membrane fuel cells (PEMFC), especially those with ultralow loading of Pt. Herein, an economical, highly durable, and efficient catalyst consisting of structurally ordered intermetallic Pt 3 Co alloy nanoparticles with ultralow Pt loading (1.4 wt %) supported on hierarchically porous carbon structure (three-dimensional, 3D Pt 3 Co/C) were synthesized with large-scale production by the NaCl-template-assisted approach. The obtained best sample, 3D Pt 3 Co/C#1, exhibited mass activities of 11.56 and 0.70 A mg Pt -1 for oxygen reduction reactions (ORRs) in alkaline and acidic electrolytes, which are 60.8 and 6.4 times those of commercial Pt/C, respectively. Furthermore, the 3D Pt 3 Co/C#1 exhibited excellent stability both in acidic and alkaline electrolytes, with almost no decay of the half-wave potential after 5000 potential cycles. This work proposes a new high-yielding, simple, and environmentally friendly method to fabricate excellent Pt-based alloy electrocatalysts with ultralow loading of Pt, which opens up new hopes for the development of PEMFC.

• TM/TM -N- C(TM = Fe, Co, Ni) carbon nanosheets were fabricated from lysine and NaCl. • Ni/Ni -N- C demonstrates the highest ORR-OER stability over a wide potential window. • Ni/Ni -N- C delivers remarkable performance for rechargeable Zn-air battery. • Synergistic effect between Ni and Ni-N 4 -C is critical to OER activity. • Durability of Ni/Ni -N- C is ascribed to stable Ni3+-N for protecting carbon. Carbon has been deemed promising electrocatalyst for oxygen reduction/evolution reaction (ORR/OER). However, most carbon materials are not stable in highly oxidative OER environments. Herein, nitrogen (N) and transition metal (TM) co-doped carbon nanosheets hybridizing with transition metal (TM/TM -N- C, TM = Fe, Co, Ni) are developed from biomass lysine by employing a NaCl template and molten-salt-promoted graphitization process. Among the as-synthesized TM/TM -N- C, the Ni/Ni -N- C with Ni nanocubes embedded in carbon demonstrates an excellent ORR-OER stability during the potential of 0.06–1.96 V. The rechargeable Zn-air battery with the fabricated Ni/Ni -N- C as the cathode catalyst produces a low voltage gap of 0.773 V, which is only slightly increased by 5 % after 150 cycles testing. Combined experimental and theoretical studies reveal that the exceptional activity and ORR-OER wide potential durability of Ni/Ni -N- C can be ascribed to highly active Ni-N 4 -C configuration, synergistic effect between Ni and Ni-N 4 -C, carbon nanosheets structure and formation of stable Ni3+-N for protecting carbon from oxidation. [ABSTRACT FROM AUTHOR]

Molybdenum phosphide (MoP) is a prospective non-precious catalyst for hydrogen evolution reaction (HER), though its HER elctrocatalytic performance need to be further enhanced. We first report a facile, easy-scalable and low-cost approach for fabricating porous lamellar MoP/C hybrids by simply mixing the common ingredients of ammonium molybdate, ammonium dihydrogen phosphate, dicyandiamide and sodium chloride (NaCl), followed by freeze-drying, annealing and water-washing. Here, NaCl is used as pore-forming and template-directing agent during the high-temperature annealing and "cooling recrystallization" process. Highly crystalline and ultrafine MoP nanoparticles are intimately wrapped by lamellar carbon nanosheets. The lamellar conductive architecture with ultrathin and porous carbon nanosheets provides multiple attractive properties for HER, such as impeding the growth of nanoparticles, offering an expressway for boosting mass/charge transfer, and delivering large specific surface area with numerous exposed eletrocatalytic sites. Consequently, the MoP/C (NaCl) electrocatalyst presents a low HER overpotential of 118 mV at 10 mA cm−2 with a small Tafel slope of 50.7 mV dec−1 in 0.5 M H 2 SO 4 , as well as robust stability. Moreover, a home-made electrolyzer using MoP/C (NaCl) as cathode achieves 0.71 A cm−2 at 2 V cell at 80 °C, and is operated stably for more than 3300 min at 150 mA cm−2. Image 1 • Porous lamellar MoP/C nanosheets are achieved with the assistance of NaCl. • The MoP/C (NaCl) electrocatalyst presents an enhanced HER activities. • A home-made electrolyzer using MoP/C (NaCl) achieves 0.71 A cm−2 at 2 V cell. [ABSTRACT FROM AUTHOR]

Tailoring composition and morphology of electrocatalysts is of great importance in improving their catalytic performance. Herein, a salt-templated strategy is proposed to construct novel multicomponent Co/Co x M y (M = P, N) hybrids with outstanding electrocatalytic performance for the oxygen evolution reaction (OER). The obtained Co/Co x M y hybrids present porous sheet-like architecture consisting of many hierarchical secondary building-units. The synthetic strategy depends on a facile and effective dissolution-recrystallization-pyrolysis process under NH 3 atmosphere of the precursors, which does not involve any surfactant or long-time hydrothermal pretreatment. That is different from the conventional methods for the synthesis of hierarchical nitrides/phosphides. Benefitting from unique composition/structure-dependent merits, the Co/Co x M y hybrids as a typical Mott-Schottky electrocatalyst exhibit good OER performance in an alkaline medium compared with their counterparts, as evidenced by a low overpotential of 334 mV at 10 mA cm -2 and a small Tafel slope of 79.2 mV dec -1 , as well as superior long-term stability. More importantly, the Co/Co x M y +Pt/C achieves higher voltaic efficiency and several times longer cycle life than conventional RuO 2 +Pt/C catalysts in rechargeable Zn-air batteries. It is envisioned that the present work can provide a new avenue for the development of Mott-Schottky electrocatalysts for sustainable energy storage., (© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Food-waste-derived biochar structures obtained through pyrolysis and with different NaCl concentrations were investigated. Increased NaCl concentration in the samples inhibited cellulose and lignin decomposition, ultimately increasing the biochar yield by 2.7% for 20%-NaCl concentration. NaCl added in solution state exhibited templating effects, with maximum increases in the Brunauer–Emmett–Teller (BET) surface area and pore volume of 1.23 to 3.50 m2∙g−1 and 0.002 to 0.007 cm3∙g−1, respectively, after washing. Adding a high concentration (20%) of NaCl reduced the BET surface area. In contrast, the mean pore diameter increased owing to the increased NaCl clustering area. Increased NaCl clustering with increased added NaCl was shown to have positive effects on NaCl removal by washing. Furthermore, as the NaCl adhered to the KCl scattered in the food waste, a high NaCl concentration also had positive effects on KCl removal. This study reports on an investigation on the effects of varying NaCl concentrations injected in solution form on the structure of food-waste biochar during pyrolysis. The templating effect was considered using both added NaCl and NaCl already contained in the food waste, with implementation of a desalination process essential for food-waste treatment for recycling. [ABSTRACT FROM AUTHOR]