Coordination Effect-Promoted Durable Ni(OH)_(2) for Energy-Saving Hydrogen Evolution from Water/ Methanol Co-Electrocatalysis

Electrocatalytic water splitting is a viable technique for generating hydrogen but is precluded from the sluggish kinetics of oxygen evolution reactions(OER).Small molecule oxidation reactions with lower working potentials,such as methanol oxidation reactions,are good alternatives to OER with faster kinetics.However,the typically employed Ni-based electrocatalysts have poor activity and stability.Herein,a novel three-dimensional(3D)-networking Modoped Ni(OH)_(2) with ultralow Ni-Ni coordination is synthesized,which exhibits a high MOR activity of 100 mA cm^(−2) at 1.39 V,delivering 28 mV dec^(−1) for the Tafel slope.Meanwhile,hydrogen evolution with value-added formate co-generation is boosted with a current density of more than 500 mA cm^(−2) at a cell voltage of 2.00 V for 50 h,showing excellent stability in an industrial alkaline concentration(6 M KOH).Mechanistic studies based on density functional the-ory and X-ray absorption spectroscopy showed that the improved performance is mainly attributed to the ultralow Ni-Ni coordination,3D-networking structures and Mo dopants,which improve the catalytic activity,increase the active site density and strengthen the Ni(OH)_(2)3D-networking structures,respectively.This study paves a new way for designing electrocatalysts with enhanced activity and durability for industrial energy-saving hydrogen production.

Axial Coordination Effects of Pyridine on the Electrochemistry of (TPP)Co in 1,2-Dichloroethane Solution

The electrochemistry of (TPP)Co in the presence of pyridine was investigated in dichloroethane solution by cyclic voltammetry. With the addition of pyridine to the solution, the reduction peaks of the axial complex compounds, (TPP)Co(III)(Py) and (TPP)Co(III)(Py)(2) were observed. It was found that the reduction peak of Co(II)/Co(I) shifted to about -1.20V (SCE) with the increase of added pyridine. The new reduction peak may be attributed to the direct reduction of the axially complex (TPP)Co(II)(Py).

Factors of Impacting the Coprecipitation Process for Synthesizing CoTi-substitued Barium M-type Ferrite Ultrafine Powder

The effect of pH values on synthesizing single-phase CoTi-substituted barium M-type ferrite ultrafine powders,and BaCoTiFe- 10O- 19, was investigated employing corrosion versus pH plot (E-pH plot) for metal element, thermodynamic calculation, and co-dump coprecipitation. The pH values of complete coprecipitation of all Fe 3+, Ti 4+, Co 2+ and Ba 2+ cations are 9-12 and higher than 7.9 on the basis of E-pH plot analysis and thermodynamic calculation, respectively. The minimum pH value necessary to the formation of single-phase BaCoTiFe- 10O- 19 is 8.5 in the light of the co-dump coprecipitation.These results indicate that the coprecipitation process for synthesizing CoTi-substituted barium M-type ferrite ultrafine powders is simultaneously influenced by synergetic coprecipation effect of cations and coordination effect of Cl-anions. The test time of the minimum pH value corresponding to forming a series of single-phase CoTi-substituted barium M-type ferrite ultrafine powders,and BaCo-xTi-xFe- 12-2xO- 19, may be significantly reduced by using the effects of two new factors on the coprecipitation process.

Electrochemical Study of Phosphine Cobalt(Ⅱ) Complex with 2-mercaptobenzothiazole

Cyclic voltammetry is used to study the electrochemical behavior of CoCl 2, Co(dppe) 2Cl 2 and Co(mbt S,N) 2(dppe) [Hmbt=2 mercaptobenzothiazole; dppe=1,2 (diphenylphosphino)] in DMF or MeCN solution with 0.1 mol·L -1 Bu n 4NBF 4 as electrolyte on the Pt electrode. The results indicate that the reduction potential, transfer coefficient and diffusion coefficient of Co(Ⅱ), Co(dppe)(Ⅱ) and Co(mbt S,N) 2(dppe) in DMF and MeCN depend on the solvent coordinated species, the volume and structure of ion. This is the characterization of the synergistic coordination effect.

The effect of domestic and foreign trade coordination on technological innovation： complements or substitutes？

Based on the theory of technology spillover in international trade, this paper discusses the technological innovation effect of trade by taking the influence of domestic trade into account. Under the constraint of the production possibility frontier, there is either complementarity or substitutability between domestic and foreign trade. It must be decided whether resources should be concentrated in one of the sectors （trade specialization） or instead allocated equally （trade equalization） between the two sectors. This paper firstly discusses how domestic trade and foreign trade work together to influence technological innovation, and how trade equalization and specialization affect different types of innovation. Using a provincial-level panel dataset from 2007 to 2015 in China, this paper constructs the indicators of domestic and foreign trade linkage and examines the impact of trade on innovation. The findings show that trade equalization mainly promotes incremental innovation, while trade specialization improves radical innovation. Thus, in the area of incremental innovation, attention should be paid to the equalized development of domestic and foreign trade, while in areas pursuing radical innovation, emphasis should be put on the specialization of the trade sector, avoiding equal allocation of resources to the two sectors.

Palladium-assisted Metal Patterning on Polyimide Surfaces

A novel method of patterning high precision copper conductive micropatterns on flexible polymer substrate(polyimide)is developed.We utilized the coordination effect between palladium salts and pyridine structures to fix the palladium chloride(PdCl_(2))on the surface of polymer film while the 2,6-dimethylpyridine structures formed in the specific areas under ultraviolet light guaranteed the resolution of final patterns.Simultaneous thermal reduction of PdCl_(2) on the surface can be achieved in the process of thermal cyclization of the polymer substrate.As a consequence,the obtained polyimide(PI)film can be patterned with conductive copper micropatterns directly by electroless plating.In particular,we accomplished the deposition of high precision copper pattern with a minimum line width of 50μm and minimum line spacing of 20μm on PI thin films(thickness~10μm)by electroless plating.The prepared conductive copper micropatterns exhibit a low resistivity of 1.78μΩ·cm the same as the pure block copper.And the relationship between the structures of the polymer chains and the physical properties of polymer substrates,such as the dimensional stability,mechanical and dielectric properties were also discussed in detail.This simple and novel method of patterning metal on the polymer surface does not need to achieve the catalytic metal adhesion required for electroless plating at the cost of destroying the substrate surface and avoiding the introduction of unstable interlayers.This patterning method is compatible with the current roll-to-roll production process and can be used to develop high-performance micro-integrated circuits.