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A series of WS2/Co9S8 nanoparticles (NPs) supported on N, S co‐doped mesoporous carbons were prepared via the molten salts process. Glucose, WCl6 and CoCl2 were used as carbon, tungsten and cobalt precursors, respectively. Thiourea were utilized as nitrogen and sulfur precursor. The common inorganic salts were the porogens, which can be removed and recycled. The molar ratio of the precursors can affect the porosities of the catalysts, which can further determine the electrocatalytic performance. The sample of G2.5TWCo shows the best HER performance due to the high electrochemically active surface area and low electrochemical impedance. [ABSTRACT FROM AUTHOR]

A molten salts strategy was developed to synthesize Co2P nanoparticles (NPs) embedded N, P co‐doped mesoporous carbon. No solvent was introduced in the synthesis process. Moreover, the common inorganic salts were utilized as the templates, which could be removed and recycled by water washing. The characterization results exhibited that the final products consisted of Co2P NPs and carbon. The amounts of the salts determined the porosities of the as‐obtained sample, which further effect the activities for electrocatalytic hydrogen evolution reaction (HER). The optimal sample of GUCo‐0.2NaCl showed the best HER performance among these as‐obtained electrocatalysts, including small Tafel slope and low overpotential. [ABSTRACT FROM AUTHOR]

A solvent-free strategy was found to prepare MoP nanoparticle (NP) embedded, N, P co-doped carbon. The characterization results revealed that the mass ratios of the precursors can determine the samples' structures and can affect the electrocatalytic activities towards the hydrogen evolution reaction (HER). These catalysts showed excellent HER performance. [ABSTRACT FROM AUTHOR]

The functional groups in porous carbon generally suffer a severe loss during the high‐temperature carbonization. Instead, the low‐temperature synthesis of carbon featuring porous structures and abundant functional groups is not only a solution that evades the pitfalls of pyrolysis but also is of significance for the development of synthetic methodology. Herein, a liquid metal interfacial engineering strategy is reported for the synthesis of porous carbon using CCl4 as the carbon precursor and sodium‐potassium alloy (NaK) as the reducing agent, which is superior to traditional synthetic methods because it enables the engineering of a highly active liquid metal alloy microemulsion to directly generate porous carbon at ambient temperature. As synthesized porous carbon featured abundant carbon‐chlorine bonds can be tandem‐grafted with imidazole and 1,2‐dibromoethane to achieve a CO2 cycloaddition catalyst, which exhibits excellent catalytic activity, in addition to exceptional stability. [ABSTRACT FROM AUTHOR]

We developed a molten salts process to prepare Co9S8 nanoparticles (NPs) entrapped, S, N co‐doped carbons. Cobalt chloride was used as the cobalt source. The melamine‐formaldehyde (MF) resin provided the carbon source and nitrogen source, and thiourea provided sulfur source. In addition, common inorganic salts were added as templates to generate pores. The characterization results showed that the prepared materials contained high contents of N, S and Co, and were mesoporous composites. At the same time, the porosity of electrocatalyst depended on the type of salt and the mass ratio of precursor to salt, which further affected the electrocatalytic activity of hydrogen evolution reaction (HER). The best prepared catalyst showed excellent HER performance. The onset overpotential of the catalyst was low (33 mV) and had a small Tafel slope (61.1 mV dec−1), in addition to good stability in alkaline media. [ABSTRACT FROM AUTHOR]

A series of Co9S8 nanoparticles (NPs) embedded, N, S co‐doped mesoporous carbons were synthesized by the combination of evaporation induced self‐assembly (EISA) method and simple pyrolysis method. Melamine formaldehyde (MF) resin was used as carbon and nitrogen precursor. CoCl2 and thiourea were utilized as cobalt and sulfur precursors, respectively. The as‐obtained samples possessed mesoporous structure. The optimized sample of MF4.0T6.0 exhibited excellent electrochemical performance towards hydrogen evolution reaction (HER) in wide pH range, which achieved a current density of 10 mA cm‐2 at 163 mV (pH 0), 149 mV (pH 14), and 325 mV (pH 7). [ABSTRACT FROM AUTHOR]

A solvent‐free strategy was developed to synthesize MoS2/Mo2C embedded, N, S co‐doped carbon via a green and environmentally friendly process. The precursors were blended and carbonized under the inert atmosphere. Water and other solvents were not involved in the whole synthesis process. According to the characterization results, the as‐received samples consisted of Mo2C, MoS2, and carbon with mesoporous structures. Moreover, the obtained sample possessed a high BET surface area (373.3 m2 g−1), as well as high electrochemical active surface area (145.4 mF cm−2). When utilized as the electrocatalyst towards hydrogen evolution reaction (HER), the optimal sample of T2.0G4.0Mo1.0 revealed superior electrochemical activity in alkaline media, which could show a low overpotential and an excellent stability. [ABSTRACT FROM AUTHOR]

We developed a salt-template strategy to prepare MoS 2 nanoparticles (NPs) embedded, N, S co-doped carbons via the solid-state process. The addition of the inorganic salt played two main roles in the synthetic proceeding. First, the salts could be utilized as the templates to produce the mesopores, which could be removed by simple washing process. Second, the salts could promote the formation of MoS 2 NPs. The as-received electrocatalyst, K-G4.0T2.0Mo1.0, possessed high BET surface area of 446 m2 g−1, in addition to high double layer capacitance of 24.5 mF cm−2 in the alkaline media. When evaluated as the electrocatalyst for hydrogen evolution reaction (HER), K-G4.0T2.0Mo1.0 demonstrated excellent performance in the alkaline and neutral medias. In details, K-G4.0T2.0Mo1.0 showed a low overpotential of 173 and 358 mV to afford 10 mA cm−2 under alkaline and neutral conditions, respectively, as well as outstanding durability. • A salt-assisted strategy was developed to synthesize mesoporous carbon. • The porosities and the crystalline structures of the samples could be tuned. • K-G4.0T2.0Mo1.0 showed outstanding electrocatalytic performance towards HER. [ABSTRACT FROM AUTHOR]

Abstract: Nitrogen‐doped carbon xerogels (NDCX) functionalized with various nitrogen functionalities are synthesized and used as supports for Pd nanoparticles (NPs) for selective hydrogenation reactions. The nitrogen doping not only induces the formation of surface basic sites that can connect with the Pd NPs by donating electrons to the unoccupied d orbital of Pd atoms and improve the Pd dispersion, but it also leads to C–N–C hybrid rings that can interact with substrates containing electron‐rich carbon rings, increasing the reaction activity. So far, the Pd/NDCX shows >95 % 1,5‐cyclooctadiene (COD) conversion and cyclooctene (COE) selectivity within 90 min for selective hydrogenation of COD to COE, and the activity can be recovered after washing the catalyst. Moreover, the catalyst can be applied to various substrates containing C=C and/or −NO2 groups with considerable conversion and selectivity. Experimental results and DFT theoretical calculations suggest that the pyridinic nitrogen plays an important role in the reaction, as it is not only the adsorption site of Pd NPs for H2 activation, but it also serves as the active site for COD activation. On these bases, a mechanism for the reaction is proposed. [ABSTRACT FROM AUTHOR]

A series of Co 9 S 8 nanoparticles (NPs) entrapped, N, S co-doped carbons were fabricated by using salts as the templates, which involved grounding, carbonation, and acid washing. Various inorganic salts, such as NaCl, KCl, MgCl 2 , and AlCl 3 , could be used as the porogens. The porosities of the products could be tuned by the ratios of precursors, annealing temperatures, and kinds of salts. When KCl was adopted, the sample of K-GTCo0.6-900 showed a high BET surface area (773 m2 g−1). Furthermore, the electrocatalytic results exhibited that the high surface area could enhance electrocatalytic activity for HER under alkaline condition. To deliver 10 mA cm−2, K-GTCo0.6-900 possessed low overpotential of 196 mV, as well as good stability. Co 9 S 8 nanoparticles embedded, N, S co-doped carbons were synthesized via a molten salts process. The types of the salts could determine the porosities of the products. K-GTCo0.6-900 displayed outstanding HER performance in alkaline media. Image 1 • Co 9 S 8 NPs embedded, N, S co-doped carbons were synthesized via a molten salts process. • The types of the salts could determine the porosities of the products. • K-GTCo0.6-900 displayed outstanding HER performance in alkaline media. [ABSTRACT FROM AUTHOR]

Correction for ‘Co3O4-nanoparticle-entrapped nitrogen and boron codoped mesoporous carbon as an efficient electrocatalyst for hydrogen evolution’ by Duihai Tang et al., Dalton Trans., 2019, DOI: 10.1039/c8dt05033c. [ABSTRACT FROM AUTHOR]

Novel mesoporous carbon/silicon carbide (C/SiC) composite was synthesized via self-templating method. The synthesis utilizes salt byproducts as the internal self-forming templates. When using as the supercapacitor electrode, the C/SiC composite exhibits a specific capacitance of 220 F g −1 , an outstanding cycling stability, and a good rate capability. [ABSTRACT FROM AUTHOR]

A molten salt strategy was proposed to prepare a series of electrocatalysts for hydrogen evolution reaction (HER) with salts as templates, which consisted of Co 9 S 8 nanoparticles (NPs) and N, S co-doped mesoporous carbons. The porosities, heteroatoms contents, and crystalline structures of the final electrocatalysts were determined by the types of salts and the calcining temperatures. When KCl/NaCl, KCl/LiCl, and NaCl/CaCl 2 were adopted as the molten salts, Co 9 S 8 NPs embedded, N, S co-doped carbons were obtained. However, when CaCl 2 and ZnCl 2 were used as the molten salts, Co 9 S 8 could not be synthesized. The characterization results exhibited that alkali metal atoms could be introduced in the lattices of Co 9 S 8. The combination of experimental and theoretical results revealed that Na and K atoms doping improved the electrocatalytic performance for HER. GTCo900-KCl/NaCl possessed the best HER activity, delivering a current density of 10 mA cm−2 at 54 mV in acidic media, 142 mV in neutral media, and 103 mV in alkaline media. • Co 9 S 8 NPs entrapped, N, S co-doped carbons were prepared via molten salt methods. • The calcining temperatures and types of salts affect the mesoporous structures. • Na and K atoms doping improve the electrocatalytic performance for HER. [ABSTRACT FROM AUTHOR]

• A facile solvent-free method was developed to synthesize mesoporous carbon. • The porosities and the heteroatoms contents of the samples could be tuned. • G2.0T1.0Co0.3–900 displayed outstanding electrocatalytic activities towards HER. A facile solvent-free method was developed to synthesize Co 9 S 8 nanoparticles entrapped, N, S-codoped mesoporous carbon, which involved two steps, including hand milling and carbonation. This synthetic route did not require any solvent during the entire process. Moreover, no water and/or acid solution were needed to remove the impurity from the calcined samples. The final products had mesoporous structures, as well as high Co, N, and S contents. In details, N and S atoms both doped into the carboneous matrix, and the Co 9 S 8 nanoparticles also dispersed well in the composites. The characterization results revealed that the ratios of the precursors and the calcination temperatures both determined the porosities of the final products, which could further affect the electrocatalytic activities. The optional sample, G2.0T1.0Co0.3–900, revealed excellent electrocatalytic activities for hydrogen evolution reaction (HER) under acidic condition, requiring overpotential of 71 mV to afford a current density of 10 mA cm−2. Additionally, G2.0T1.0Co0.3–900 also showed superior stability and duration. [ABSTRACT FROM AUTHOR]