Through-hole cross-section of PCB
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•In this paper, charge density difference and charge transfer are used to describe the change process of electroplated PCB.•The structure of PCs and ...PCCS was optimized for many times, and the reaction process was recorded in detail.
Cl− dissolved in electroplating solution is one of the most representative additives. Although the coordination structure of Cl− and polyethylene glycol (PEG) has been investigated, the coordination structure was still highly puzzling. The synergistic effect of PEG and Cl− in electroplating copper is analyzed and discussed by a series of design experiments and DFT. For the experiment, the through-hole of a printed circuit board (PCB) is electroplated with an acid plating solution, and the inhibition ability of complex and nucleation and growth process of Cu are studied by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and chronoamperometry (CA). Theoretical analysis, the adsorption energy and Bader charge are computed by the firstprinciples. Comparing experimental and theoretical results, the copper plating solution with Cl− (PCC) shows better inhibition than that without Cl− (PC), and the average thickness of coating in the hole (ATCH) of PCB are 22.33 μm and 57.76 μm and nucleation and growth process of Cu requires a smaller potential with Cl− in the plating solutions. The energy curve shows that the adsorption energy of PCC* is higher than that of PC*. Due to the coordination of Cl−, the ability of Cu2+/1+ in PCC* to obtain electrons is weakened, thereby suppressing the inability of Cu2+/1+ to be reduced. This work not only illustrates clearly the inhibition ability of Cl− and PEGbut also highlights the crucial roles of charge capacity and energy barriers, which can help decipher the electroplating mechanism.
With the gradual development of high density and high integration of printed circuit board (PCB), the electroplating technology of PCB has been widely paid attention by researchers and enterprises, ...among which the through-hole (TH) electroplating of PCB is the key to realize the multi-layer interconnection. Many researches improve the electroplating quality of TH by optimizing the technological conditions. In this paper, the development trend and challenges of TH electroplating are introduced. In addition, the research mechanism of TH electroplating as well as the influence of additives and periodic pulse reverse electroplating on TH electroplating are also introduced. In addition, the methods of studying the electroplating process through numerical model and optimizing the electroplating process are analyzed and summarized. By adding additives to the bath and deeply studying the mechanism of TH electroplating through numerical simulation, the technological parameters of TH interconnection were optimized. The research status of TH electroplating was reviewed. The deposition mechanism was studied by theoretical calculation method and the electrode process was changed by using additives to improve the quality of TH electroplating.
Graphical abstract
As a crucial material for fabrication of lithium-ion battery current collector, the properties of electrodeposited copper foil are closely related to the battery performances. How to improve its ...properties is thus of great importance for battery design and manufacturing. In this paper, we reported a novel composite additive, consisting of collagen, glycerol, hydroxyethyl cellulose, and sodium polydisulfide dipropane sulfonate, for electrodeposition of high-quality copper foil from conventional acid copper sulfate bath. Meanwhile, a pulse superimposed on direct current was used during the preparation process of copper foil. It was demonstrated that the additive could improve the foil’s performances, through changing the kinetic parameters of copper electrodeposition in sulfate bath. The optimized bath has a higher allowable current density during superimposed current electrodeposition, in contrast to the situation in direct current electrodeposition. This may then lead to an increase in deposition rate of copper foil, and a further improvement in surface roughness, grain size, residual stress, as well as elongation. Specially, the superimposed current offers a number of adjustable parameters for modulating copper foil’s properties in a wide range.
Graphic abstract
In order to increase the resistance of electrogalvanized steel to corrosive wear, nanocrystalline zinc coating was electrodeposited onto the steel substrate using a sulfate bath with polyacrylamide ...as grain refiner. Corrosive wear tests were performed in a simulated seawater solution to evaluate the performance of the nanocrystalline zinc coating with its grain size around 40nm, in comparison with that of coarse-grained zinc coating (grain size~5μm). It was demonstrated that material loss of the coarse-grained zinc coating was 39 times as large as that of the nanocrystalline one. The considerably higher corrosive wear resistance of the nanocrystalline zinc coating largely benefited from its increased mechanical strength due to nanocrystallization and higher surface activity, which improved the passivation capability with the formation of a more protective oxide scale. Detailed analyses were conducted to clarify the mechanism responsible for the improvements.
•Nanocrystalline zinc coating (40 nm) is prepared by nano-electrodeposition in sulfate electrolyte with polyacrylamide.•The average electron work function of coarse-grained zinc is 0.195 eV higher than that of nanocrystalline zinc.•The corrosive wear resistance of galvanized steel was increased by almost 39 times.
Highlights
A promising solar-powered environmentally friendly process for the synthesis and application of catalysts for hydrogen evolution reaction has been proposed.
A delicate NiCo(OH)
x
-Co
y
W ...catalyst with a bush-like heterostructure was realized via gas-template-assisted electrodeposition, followed by electrochemical etching process.
The excellent catalytic effect of NiCo(OH)
x
-Co
y
W for the hydrogen evolution reaction was systematically investigated through various physical and electrochemical analyses.
To achieve high efficiency of water electrolysis to produce hydrogen (H
2
), developing non-noble metal-based catalysts with considerable performance have been considered as a crucial strategy, which is correlated with both the interphase properties and multi-metal synergistic effects. Herein, as a proof of concept, a delicate NiCo(OH)
x
-Co
y
W catalyst with a bush-like heterostructure was realized via gas-template-assisted electrodeposition, followed by an electrochemical etching-growth process, which ensured a high active area and fast gas release kinetics for a superior hydrogen evolution reaction, with an overpotential of 21 and 139 mV at 10 and 500 mA cm
−2
, respectively. Physical and electrochemical analyses demonstrated that the synergistic effect of the NiCo(OH)
x
/Co
y
W heterogeneous interface resulted in favorable electron redistribution and faster electron transfer efficiency. The amorphous NiCo(OH)
x
strengthened the water dissociation step, and metal phase of CoW provided sufficient sites for moderate H immediate adsorption/H
2
desorption. In addition, NiCo(OH)
x
-Co
y
W exhibited desirable urea oxidation reaction activity for matching H
2
generation with a low voltage of 1.51 V at 50 mA cm
−2
. More importantly, the synthesis and testing of the NiCo(OH)
x
-Co
y
W catalyst in this study were all solar-powered, suggesting a promising environmentally friendly process for practical applications.
Improving the density of Na
3
Zr
2
Si
2
PO
12
(NZSP) solid electrolyte is crucial for its application in solid-state sodium batteries. Here, bismuth oxide with low melting point has been evaluated as ...a sintering aid for NZSP solid electrolytes. Research has found that NZSP doped with 5 mass% Bi
2
O
3
increases grain boundary mobility by 3.1 times and has an ionic conductivity of 4.78 × 10
−3
S cm
−1
, with a minimum activation energy of 0.30 eV, approximately 5 times that of undoped Bi
2
O
3
. This is because the electrolyte density increased from 77.3 to 93.7%. Compared with the region III process of NZSP without Bi
2
O
3
, Bi
2
O
3
promotes the densification process of Bi
2
O
3
dopant coarsening in region III. The constant current cycle of Na | NZSP-5 mass% Bi
2
O
3
| Na symmetric battery indicates that no short circuit will occur within 1200 h. The discharge capacity of solid-state batteries at 0.2 C is 98.5 mAh g
−1
. This indicates that NZSP doped with 5% Bi
2
O
3
is a good electrolyte choice for sodium-ion batteries.
Adsorption behaviors of N-butyl-methyl piperidinium bromide (PP14Br) at Cu (001) surface under different electric fields were investigated using molecular dynamics (MD) simulations. We predicted ...PP14Br could be used as a new leveler for through-hole copper electroplating. In the through-hole electroplating experiments, PP14Br was employed as a leveler. The results of electroplating confirmed the prediction. The electrochemical tests were characterized by potentiodynamic polarization and galvanostatic measurements using rotating disk electrode operated at 100 and 1000rpm.
► A new leveler (PP14Br) for through-hole electroplating is found. ► Study the adsorption behavior of PP14Br using molecular dynamic (MD) simulations. ► Predict the leveler using MD simulations and confirm it through experiments.
In order to fabricate copper coatings with excellent brightness, a cationic additive was screened by applying the electrochemical method and the theoretical calculation method. The
...adsorption-coordination coupling inhibition
mechanism was proposed to illustrate the influence of the additive methylene blue (MB). The electrochemical behavior of copper electrodeposition influenced by MB was investigated by cyclic voltammetry and chronoamperometry. The copper electrodeposition under the influence of MB is diffusion-controlled, while the nucleation and growth of coating are 3D diffusion-controlled instantaneous nucleation processes. The electroplating process was optimized and bright copper coating can be obtained at wide range of current density according to SEM analysis and AFM analysis. The XRD was used to study the phase structure under the influence of current density and (1 1 1) surface is obtained preferentially with the increase of current density. The mean grain size is within 100 nm according to Scherrer’s formula, illustrating that nanocrystalline copper coating is obtained.
Graphical abstract
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•Synergistic suppressing mechanism was illustrated to explain the strong suppressing ability of Brilliant Green on copper electrodeposition.•The strong suppressing effect of Brilliant ...Green was confirmed by electrochemical tests.•Copper superconformal electrodeposition was achieved and high FP values (80.52 % to 84.38 %) with low SDT (about 28 μm) was obtained in the optimized condition.
Finding proper additive to achieve copper superconformal electrodeposition is significantly important. Brilliant Green exhibits excellent suppressing ability to the copper electrodeposition according to electrochemical analysis. Meanwhile, 100 mg/L was selected as the optimum value based on the convection-dependent adsorption behavior analysis of Brilliant Green. The interaction among three different additives was also investigated by applying chronopotentiometry as well as Brilliant Green compete to absorb on the cathode surface with SPS. Besides, the introduction of Brilliant Green can improve the transport of cupric ions (Cu2+). The nucleation and growth of copper deposition is 3D diffusion-controlled instantaneous growth process at high overpotential but 3D diffusion-controlled mixing growth process at low overpotential. The synergistic suppressing mechanism was proposed to explain strong suppressing effect of BG on reduction of Cu2+ and the reaction pathways was studied theoretically. Copper interconnect layer with high FP values (80.52 % to 84.38 %) was obtained with low SDT (about 28 μm) after electroplating process was optimized. The surface morphology under the influence of Brilliant Green is compact and uniform and the grain size is reduced by Brilliant Green.
With the global proliferation of 5G technology, advancing electronic interconnection technologies has become critically important. The development of high-quality electrolytic copper foils, essential ...for efficient signal transmission, has garnered considerable attention. To mitigate the "skin effect" that could impair signal transmission and to ensure robust adhesion of electrolytic copper foils to the substrate, it's necessary to roughen the copper foils. This roughening process aims to substantially enhance the peel strength of the copper foils without exceeding the bounds of acceptable roughness. An effective strategy to achieve this involves the use of additives to refine the micro-coarsened surface of the copper foils. In this context, we have explored the impact of additives such as carrageenan, guar gum, and SPS on the surface morphology, roughness, and peel strength of electrolytic copper foils. Three types of additives can improve the performance of micro-roughened copper foil. Through electrochemical tests, it was found that all three types of additives have the effect of increasing cathodic polarization. The adsorption behavior of different additives was studied through theoretical calculations. By hybriding the three additives, two micro-coarsening systems were screened to obtain the lowest roughness and the highest peel strength, respectively. At the same time, the relationship between peel strength and surface area was verified, with the larger surface area resulting in greater peel strength. Finally, the synergistic effect of the three additives on increasing cathodic polarization was verified through chronopotentiometry.
Graphical Abstract
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