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[Display omitted] • According to the theoretical and experimental analysis results, the Cl- can accelerate after complexation with SPS and become the "engine" of copper electroplating. • In this paper, charge density difference, charge transfer and dynamic analysis are used to describe the effect of the SCS and SCCS on the copper surface changes. The acceleration effect of Cl- and bis-(sodium sulfopropyl)-disulfide (SPS) in electroplating solution was analyzed by various electrochemical methods and dynamic simulation with DFT. The cathodic polarization, solution resistance, and nuclear transfer coefficient of the two electroplating systems were analyzed by electrochemical methods; OLYMPUS confocal laser microscope was used to explore the throwing power (TP) and average thickness of the coating (ATCH) in PCB. The multi-step energy change of two systems are used to analyze the reduction process of Cu2+/1+ based on the first principles. The TP and ACTH of SCS (SPS-Cu2+/1+) and SCCS (SPS-Cu2+/1+-Cl-) are 85%, 95%, 56.57 μm and 65.77 μm, respectively. Scanning electron microscope analysis shows that the nucleation rate of the SCCS system is higher than that of the SCS system in 0.2 s. In the dynamic analysis of the system, the reduction of Cu2+/1+ in the SCCS system only needs three steps, while that in the SCS system needs five steps. The experimental and theoretical results show that the reduction rate of Cu2+/1+ in the bath containing Cl- is faster than that in the bath without Cl-. [ABSTRACT FROM AUTHOR]

Abstract: The electrodeposition of metallic cobalt from a 1-butyl-3-methylimidazolium tetrafluoroborate ionic liquid was investigated. The electrochemical behavior of Co(II) in the ionic liquid on a platinum working electrode at 60°C was studied by cyclic voltammetry and chronoamperometry. The results from the cyclic voltammetry showed that the electrodeposition of metallic Co in the ionic liquid was an irreversible process and controlled by the diffusion of Co(II) on a platinum working electrode. The average value of αn α was calculated to be 0.35 and the diffusion coefficient (D 0) of Co(II) was calculated to be 1.76×10−8 cm2/s at 60°C. Chronoamperometric results indicated that the electrodeposition of Co on a platinum working electrode followed the mechanism of instantaneous nucleation and three-dimensional growth with diffusion-controlled. The cobalt plating was uniform, dense, shining in appearance with good adhesion to the platinum substrate at 60°C. The scanning electron microscope (SEM) micrographs were used to confirm that the cobalt plating was denser and finer at 60°C. Energy dispersive X-ray analysis (EDAX) profile showed that the obtained plating was pure cobalt. X-ray diffraction (XRD) pattern indicated that there was a preferred orientation direction and the average size of cobalt grains was 40nm. [Copyright &y& Elsevier]

[Display omitted] • GHNCNs_Urea was designed by introducing nitrogen source, increasing pore structures. • The GHNCNs_Urea electrocatalyst exhibited outstanding ORR activity. • The excellent ORR activity was attributed to ultra-high SSA and large pore volume. • The Zn-air battery exhibited a high peak power density and a long-term stability. When designing carbon-based electrocatalysts as Pt-free catalysts for the oxygen reduction reaction (ORR), pore structures is crucial, in addition to creating active sites. Here, N-doped carbon nanosheets were rationally designed by tactfully introducing nitrogen source into the carbonization process, which could increase the density of pore structures and effective active sites. Owing to the ultra-high specific surface area (2127 m2 g−1), large pore volume (5.77 cm3 g−1), and bimodal-pore structure (micropores and mesopores), the optimized catalyst exhibited an excellent ORR activity (a half-wave potential of 0.86 V), as well as outstanding durability and methanol tolerance in alkaline medium. Moreover, it provided excellent stability and high peak power density when used as ORR catalyst in Zn-air battery, exceeding that driven by Pt/C catalyst. This work brings a feasible and universal strategy for fabricating metal-free ORR catalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synergistic effect of Rhodamine B (RhB) was illustrated to explain the strong suppressing ability of RhB during the reduction of cupric ions. • The strong suppressing influence of RhB was confirmed by electrochemical tests. • Proper RhB is conducive to improving surface morphology and smoothness of copper interconnect layer. • Microvias filling for different blind vias radius is achieved with RhB concentration ranging from 50 mg/L to 150 mg/L. Achieving void-defect copper filling by electrodeposition on microvias is essentially important. Rhodamine B (RhB) is of excellent suppressing ability based on electrochemical analysis. Convection-dependent adsorption analysis demonstrates that 100 mg/L was the optimum value to achieve bottom-up growth. The interaction among sodium 3,3′-dithiodipropane sulfonate, polyethylene glycol, and RhB was investigated and competition adsorption between RhB and SPS is observed. Meanwhile, copper electrodeposition obeys 3D diffusion-controlled progressive nucleation process at low potential but obeys 3D diffusion-controlled instantaneous nucleation process at high overpotential. Density functional theory and in situ Raman spectra were used to study the adsorption behavior of RhB. The calculated results indicates that RhB can effectively increase the energy barrier during copper electrodeposition. The surface morphology is improved and surface roughness is lowered with proper RhB concentration. The influence of RhB on orientation and grain size was analyzed and proper RhB (100 mg/L) is conducive to the formation of Cu (1 1 1) surface and lowering the grain size. Besides, the introduction of RhB can improve the wettability, which is conducive to the bottom-up growth. The electroplating process is optimized and void-defect copper interconnect line with high quality is obtained. [ABSTRACT FROM AUTHOR]