Electrocatalytic nitrate reduction to ammonia is of great interest in terms of energy conservation and environmental protection. However, the development of abundant metal-free electrocatalysts with ...high activity, selectivity, and stability is still a big challenge. Herein, polymeric graphitic carbon nitride (g-C3N4) with controllable numbers of nitrogen vacancies is reported to exhibit high Faradaic efficiency (89.96%), selectivity (69.78%), and stability toward nitrate-to-ammonia conversion. 15N isotope labeling experiments prove the produced ammonia originating from nitrate reduction. The combined results of ex situ and in situ characterizations unveil the reaction pathway based on the captured critical intermediates. Density functional theory calculations reveal that nitrogen vacancies could introduce a new electron state at the Fermi level and promote the adsorption, activation, and dissociation of nitrate. An appropriate content of nitrogen vacancies is beneficial for modulating the adsorption energies of reaction intermediates (*NO, *NOH, *NH2, etc.), facilitating the enhancement in ammonia selectivity and Faradaic efficiency.
Electrocatalytic nitric oxide (NO) reduction is a promising strategy to produce ammonia. Developing a facile approach to synthesize efficient catalysts with enhanced NO electroreduction performance ...is highly desirable. Here, a series of Ru-doped Cu materials are constructed through
in situ
electroreduction of corresponding metal hydroxides. The optimized Ru
0.05
Cu
0.95
exhibits superior electrocatalytic performance for ammonia synthesis by using NO/Ar (1/4,
n
/
n
) as the feedstocks (Faradaic efficiency: 64.9%, yield rate: 17.68 μmol cm
−2
h
−1
), obviously outperforming Cu counterpart (Faradaic efficiency: 33.0%, yield rate: 5.73 μmol cm
−2
h
−1
). Electrochemical
in situ
Fourier transform infrared (FTIR) spectroscopy and online differential electrochemical mass spectrometry (DEMS) are adopted to detect intermediates and unveil the possible reaction pathway. The downshift of the Cu d-band center induced by Ru doping facilitates the rate-limiting hydrogenation step and decreases the desorption energy of NH
3
, leading to high Faradaic efficiency and yield of ammonia.
Electrochemical synthesis of urea provides a sustainable strategy that can be easily incorporated into currently distributed renewable energy systems. The main challenge that hindered the advancement ...of this technique lies in developing advanced electrocatalytic processes to utilize abundant and low-cost inorganic carbon and nitrogen sources for highly productive urea generation. Herein, we report an electrocatalytic reaction that converts carbon dioxide (CO2) and nitric oxide (NO) into urea, with water as the hydrogen source, under ambient conditions. The yield rate and Faradaic efficiency of urea reach 15.13 mmol g–1 h–1 and 11.26% at a current density of 40 mA cm–2 under optimized conditions. The critical intermediates of *CO and *NH2 for urea generation are obtained via the co-reduction of CO2 and NO and then continuously interconnect to form the C–N bond. A preliminary techno-economic study is performed to discuss the practical application potential of this strategy for urea production.
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•Layered 1T-MoS2/RGO nanohybrid was synthesized through a green self-assembly method.•Noble-metal-free 1T-MoS2/RGO showed excellent performances for 4-NP hydrogenation.•This green ...approach could be extended to yield RGO-based metal hydrogel.
A green and facile process was developed to prepare layered octahedral phase MoS2/reduced graphene oxide (1T-MoS2/RGO) nanocomposite by a Vitamin C-assisted self-assemble method, in which graphene oxide (GO) and LiMoS2 were used as starting materials. Catalytic performances of 1T-MoS2/RGO were evaluated by hydrogenation of 4-nitrophenol (4-NP). It was demonstrated that the prepared 1T-MoS2/RGO nanocomposite presented excellent catalytic performance and cycling stability for 4-NP reduction, which made it a promising noble-metal-free catalyst. Additionally, broadening work suggested some other RGO-based metal nanocomposite with well-defined porous structure could be also generated via this facile self-assembly method.
To investigate the effect of methyleugenol on expression of MUC5AC in nasal mucosa of rats with allergic rhinitis (AR).
Seventy-two Wistar rats were randomly divided into 6 groups:normal control ...group, AR group, loratadine group, low-dose methyleugenol group, middle-dose methyleugenol group and high-dose methyleugenol group with 12 rats in each group. AR was induced by intraperitoneal injection of ovalbumin in latter 5 groups. 10 mg loratadine q.d was given to rats in loratadine group by gavage; and 10 mg/kg, 20 mg/kg and 40 mg/kg methyleugenol were given by gavege q.d to rats in low-, middle-and high-dose methyleugenol groups, respectively. Nasal mucosa samples were obtained from rats at 1, 2, 4 and 6 weeks after drug intervention. The expression of MUC5AC protein and mRNA in nasal mucosa was detected by immunohistochemistry and real-time fluorescence quota PCR (RT-PCR), respectively.
Compared with AR, the percentage of cells staining positively for MUC5AC protein and the relative quantity of MUC5AC mRNA in
In this work, molybdenum disulfide (MoS₂) nanosheets were employed to enhance the mechanical and thermal properties of chitosan (CS), which was one of the most promising biomaterials. In order to ...promote a homogeneous dispersion of MoS₂ and improved interface interactions between CS and fillers, carboxyl functionalization was subjected to the exfoliated MoS₂ nanosheets by chemical conjugation with thioglycolic acid before compositing with CS. Afterward, the CS/MoS₂–g–COOH composite films were prepared by a simple solution blending method. Micromorphology characterizations showed that MoS₂–g–COOH nanosheets dispersed much better than unmodified MoS₂ nanosheets, which was considered to be quite beneficial for the enhanced properties of CS nanocomposites. DMA results indicated that the mechanical properties of CS were improved by incorporating with MoS₂–g–COOH nanosheets compared with neat CS and unmodified MoS₂-filled CS. The thermal stability of CS/MoS₂–g–COOH was also improved. This work demonstrated a promising route to prepare MoS₂-based polymer nanocomposites with excellent performances.
The scalable and durable electrosynthesis of high‐valued organonitrogen compounds from carbon‐ and nitrogen‐containing small molecules, especially operating at a high current density, is highly ...desirable. Here, a one‐pot electrooxidation method to synthesize formamide (HCONH2) from methanol and ammonia over a commercial boron‐doped diamond (BDD) catalyst is reported. The formamide selectivity from methanol and formamide Faradaic efficiency (FE
HCONH2
${{_{{\rm HCONH}{_{2}}}$
) achieve 73.2 % and 41.2 % at the current density of 120 mA cm−2 with high durability. The C−N bond originates from the nucleophilic attack of ammonia on an aldehyde‐like intermediate. Impressively, an 8 L electrolyzer is employed for the pilot plant test over a 2200 cm2 BDD electrode, which exhibits 33.5 % FE
HCONH2
${{_{{\rm HCONH}{_{2}}}$
at 120 mA cm−2 (current: 264 A) with a yield rate of 36.9 g h−1, demonstrating the potential of this technique for large‐scale electrosynthesis of formamide.
Boron‐doped diamond catalyst is adopted for electrooxidation synthesis of formamide from methanol and ammonia with high activity and durability. A scale‐up 8 L electrolyzer with an external renewable power supply for the production of formamide is designed to enable its scalable production (FE: 33.5 %, output: 36.9 g h−1), which shows the potential for the large‐scale electrosynthesis of formamide.
The scalable and durable electrosynthesis of high‐valued organonitrogen compounds from carbon‐ and nitrogen‐containing small molecules, especially operating at a high current density, is highly ...desirable. Here, a one‐pot electrooxidation method to synthesize formamide (HCONH2) from methanol and ammonia over a commercial boron‐doped diamond (BDD) catalyst is reported. The formamide selectivity from methanol and formamide Faradaic efficiency (FEHCONH2${{_{{\rm HCONH}{_{2}}}$) achieve 73.2 % and 41.2 % at the current density of 120 mA cm−2 with high durability. The C−N bond originates from the nucleophilic attack of ammonia on an aldehyde‐like intermediate. Impressively, an 8 L electrolyzer is employed for the pilot plant test over a 2200 cm2 BDD electrode, which exhibits 33.5 % FEHCONH2${{_{{\rm HCONH}{_{2}}}$at 120 mA cm−2 (current: 264 A) with a yield rate of 36.9 g h−1, demonstrating the potential of this technique for large‐scale electrosynthesis of formamide.
Efficient electrochemical reduction of CO
and H
O into industrial syngas with tunable CO/H
ratios, especially integrated with anodic organic synthesis to replace the low-value oxygen evolution ...reaction (OER), is highly desirable. Here, integration of controllable partial substitution of zinc (Zn) with amine incorporation into CdS-amine inorganic-organic hybrids is used to generate highly efficient electrocatalysts for synthesizing syngas with tunable CO/H
ratios (0-19.7), which are important feedstocks for the Fischer-Tropsch process. Diethylenetriamine could enhance the adsorption and accelerate the activation of CO
to form the key intermediate COOH* for CO formation. Zn substitution promoted the hydrogen evolution reaction (HER), leading to tunable CO/H
ratios. Importantly, syngas and dihydroisoquinoline can be simultaneously synthesized by pairing with anodic semi-oxidation of tetrahydroisoquinoline in a Zn
Cd
S-Amine ∥ Ni
P two-electrode electrolyzer.
CuS/MoS2 nanocomposite with high solar photocatalytic activity Meng, Nannan; Zhou, Yifeng; Nie, Wangyan ...
Journal of nanoparticle research : an interdisciplinary forum for nanoscale science and technology,
2015/7, Volume:
17, Issue:
7
Journal Article
Two-dimensional CuS/MoS
2
heterostructure with high photocatalytic activity had been successfully obtained by a simple combination of wet chemical method and hydrothermal process. CuS nanosheets had ...been successfully grown on the two-dimensional MoS
2
nanosheets uniformly and tightly. The obtained heterostructures were well characterized through X-ray diffraction patterns, transmission electron microscopy, Fourier transform infrared spectra, ultraviolet–visible diffuse-reflectance spectra, and Zeta potential measurement. Photocatalytic performance of the CuS/MoS
2
nanocomposite was evaluated toward the decomposition of methylene blue solution under natural light. The as-prepared nanocomposite showed remarkably enhanced photocatalytic activity compared with pure CuS and MoS
2
. This could be attributed to the enhanced dyestuff absorption and charge transport after the conjugation between CuS and MoS
2
.
