Different effects of cerium ions doping on properties of anatase and rutile TiO2

Pure and Ce⁴⁺ doped anatase and rutile TiO₂ were prepared by hydrothermal methods and characterized by XRD, TEM, UV-vis diffusion spectroscopy, and XPS measurements. The photocatalytic reactivity of the catalysts was evaluated by the photodegradation of Rhodamine B (RB) under ultraviolet irradiation. The photocatalytic efficiency of the rutile sample doped with an appropriate amount of Ce⁴⁺ was enhanced while all Ce⁴⁺ doped anatase samples showed a much lower activity than pure anatase. The reasons were discussed     

A new near-infrared fluorescent chemodosimeter for discrimination of sulfide from disulfide

Research on Chemical Intermediates - A new near-infrared fluorescent “turn-on” chemodosimeter (probe 1) based on dicyanomethylene-4H-chromene fluorophore for sulfide was developed....     

Hydrothermal Synthesis of Nickel Phosphate Nanorods for High‐Performance Flexible Asymmetric All‐Solid‐State Supercapacitors

Ni₂₀[(OH)₁₂(H₂O)₆][(HPO₄)₈(PO₄)₄]·12H₂O nanorods are successfully synthesized via a one‐pot hydrothermal reaction. A high‐performance flexible asymmetric all‐solid‐state supercapacitor based on the obtained Ni₂₀[(OH)₁₂(H₂O)₆][(HPO₄)₈(PO₄)₄]·12H₂O nanorods (positive electrode) and graphene nanosheets (negative electrode) is successfully assembled. It is the first report of this nanomaterial applied for all‐solid‐state supercapacitors. Interestingly, a maximum volumetric energy density of 0.446 mW h cm^?3 at a current density of 0.5 mA cm^?2 and a maximum power density of 44.1 mW cm^?3 at a current density of 6.0 mA cm^?2 are achieved by the as‐assembled device. What's more, the device also shows excellent mechanical flexibility and little capacitance change after over 5000 charge/discharge cycles at a current density of 0.5 mA cm^?2.     

Terahertz spectroscopic investigations of caffeine and 3-acetylmorphine

Experimental and theoretical investigations of THz spectral features of caffeine and 3-acetylmorphine in the region of 0.2-2.6 THz have been presented. The refractive indices and absorption coefficients of the two drugs were obtained by a terahertz time-domain spectroscopy (THz-TDS) technique. The simulated absorption spectra using the density functional theory (DFT) and Hartree-Fork (HF) are in agreement with the experimental data. The observed spectral absorption features were assigned based on DFT and HF calculation.     

High purity nanolatex prepared by ultrasonically irradiated emulsion polymerization

Ultrasonically initiated emulsion copolymerization of styrene and a cationic polymerizable surfactant (methacryloxyethyl dodecydimethyl ammonium bromide, C(12)N(+)) was successfully employed to prepare high purity copolymer nanolatex. C(12)N(+) can play the roles of an emulsifier, an initiator, and a comonomer at the same time. It has an excellent initiation efficiency and reactivity. The rate of copolymerization was high and styrene conversion achieved 95% in an hour. Nanoscale latex particles with average diameter 40 nm were obtained easily under ultrasonic irradiation. Results of FTIR, (1)H NMR and surface tension tests proved almost all surfmers had copolymerized with styrene when the C(12)N(+) concentration was more than 0.030 g/mL, indicating high purity nanolatex without residual emulsifiers was obtained.     

Electrosynthesis of α-Amino Acids from NO and other NOx species over CoFe alloy-decorated Self-standing Carbon Fiber Membranes

The conversion of industrial exhaust gases of nitrogen oxides into high-value products is significantly meaningful for global environment and human health. And green synthesis of amino acids is vital for biomedical research and sustainable development of mankind. Herein, we demonstrate an innovative approach for converting nitric oxide (NO) to a series of α-amino acids (over 13 kinds) through electrosynthesis with α-keto acids over self-standing carbon fiber membrane with CoFe alloy. The essential leucine exhibits a high yield of 115.4 μmol h⁻¹ corresponding a Faradaic efficiency of 32.4 %, and gram yield of products can be obtained within 24 hours in lab as well as an ultra-long stability (>240 h) of the membrane catalyst, which could convert NO into NH₂OH rapidly attacking α-keto acid and subsequent hydrogenation to form amino acid. In addition, this method is also suitable for other nitrogen sources including gaseous NO₂ or liquidus NO₃⁻ and NO₂⁻. Therefore, this work not only presents promising prospects for converting nitrogen oxides from exhaust gas and nitrate-laden waste water into high-value products, but also has significant implications for synthetizing amino acids in biomedical and catalytic science.     

Electrocatalytic Synthesis of Essential Amino Acids from Nitric Oxide Using Atomically Dispersed Fe on N-doped Carbon

How to transfer industrial exhaust gases of nitrogen oxides into high-values product is significantly important and challenging. Herein, we demonstrate an innovative method for artificial synthesis of essential α-amino acids from nitric oxide (NO) by reacting with α-keto acids through electrocatalytic process with atomically dispersed Fe supported on N-doped carbon matrix (AD-Fe/NC) as the catalyst. A yield of valine with 32.1 μmol mg_cat⁻¹ is delivered at −0.6 V vs. reversible hydrogen electrode, corresponding a selectivity of 11.3 %. In situ X-ray absorption fine structure and synchrotron radiation infrared spectroscopy analyses show that NO as nitrogen source converted to hydroxylamine that promptly nucleophilic attacked on the electrophilic carbon center of α-keto acid to form oxime and subsequent reductive hydrogenation occurred on the way to amino acid. Over 6 kinds of α-amino acids have been successfully synthesized and gaseous nitrogen source can be also replaced by liquid nitrogen source (NO₃⁻). Our findings not only provide a creative method for converting nitrogen oxides into high-valued products, which is of epoch-making significance towards artificial synthesis of amino acids, but also benefit in deploying near-zero-emission technologies for global environmental and economic development.     

Chemical structure and gas products of different rank coals during pyrolysis

Journal of Thermal Analysis and Calorimetry - In this study, three coal samples (long flame coal/LFC, coking coal/CC, and anthracite/AC) from the same coal seam in Huaibei coalfield were simulated...     

Ir Nanoparticles Anchored on Metal-Organic Frameworks for Efficient Overall Water Splitting under pH-Universal Conditions

The construction of high-activity and low-cost electrocatalysts is critical for efficient hydrogen production by water electrolysis. Herein, we developed an advanced electrocatalyst by anchoring well-dispersed Ir nanoparticles on nickel metal-organic framework (MOF) Ni-NDC (NDC: 2,6-naphthalenedicarboxylic) nanosheets. Benefiting from the strong synergy between Ir and MOF through interfacial Ni−O−Ir bonds, the synthesized Ir@Ni-NDC showed exceptional electrocatalytic performance for hydrogen evolution reaction (HER), oxygen evolution reaction (OER) and overall water splitting in a wide pH range, superior to commercial benchmarks and most reported electrocatalysts. Theoretical calculations revealed that the charge redistribution of Ni−O−Ir bridge induced the optimization of H₂O, OH* and H* adsorption, thus leading to the accelerated electrochemical kinetics for HER and OER. This work provides a new clue to exploit bifunctional electrocatalysts for pH-universal overall water splitting.