Hasil untuk "Industrial electrochemistry"

Justin C. Bonner, Krisztián Bali, Bishal Bhandari et al.

In flexible electronics, the substrate's durability during device processing and operation is critical to ensure good performance and long-term stability. In this article, we aim to understand the difference in thermo-mechanical durability of a transparent conducting electrode (TCE) made on polyethylene terephthalate (PET). The TCEs are composed of layers of silver (Ag) nanowires and indium zinc oxide on a PET substrate containing Ag metal bus lines. TCEs made on all substrates show similar optical, electrical, chemical, and physical properties; however, some TCEs are durable, i.e., maintain conductivity and structural integrity, during device fabrication, while others exhibit catastrophic cohesive failure and become non-conductive. To investigate whether these observations are linked to the surface properties of the PET substrates, surface-sensitive characterizations, including contact angle, ellipsometry, Fourier transform infrared spectroscopy in total attenuated reflection mode, and atomic force microscopy, are employed. Our results show that TCEs made on the bare PET side of the substrate are thermo-mechanically durable, while those fabricated on the primer side always fail when heated during device fabrication. Adhesion of TCE materials to bare PET is found to be stronger than to the primer side. Thus, realizing functional flexible electronics on plastic substrates requires a holistic design of substrate and inorganic thin film stacks, so that the thermal requirements for device fabrication and operation are met.

Jong Hyun Shim

Due to the rising price and limited resource supply chain of Li [NixMnyCoz]O2 (x + y + z = 1) (NMC) cathode material, lithium-ion battery (LIB) recycling technologies have been emerging as the best solution to address the price issue. Mainly, conventional hydrometallurgy processes have been applied to the LIB recycling field in recognition of its value. One remarkable advantage of the hydrometallurgy method is that it serves as a bridge to enable the Hydro-to-Cathode® method. However, using recycled raw materials in the production of precursor cathode materials needs to be studied in parallel with the impurity (dopant) effect. The insufficient selective impurity removal technology leads to unexpected electrochemical properties in the final NMC cathode active material, which can be doped by several different impurities. Consequently, scrutinizing dopant elements (inorganic and organic) is critical if we want to consider the Hydro-to-Cathode® method as a major recycling process of NMC cathode material.

Bingjie Zhou, Yuankai Shao, Weikang Zhu et al.

The growing energy crisis has intensified the need for efficient energy storage solutions. Biomass has emerged as a promising resource for novel energy storage devices. Lignosulfonate, a byproduct of the forestry and pulp industries, contains quinone groups and has enormous potential for electrochemical energy storage. However, due to its poor electrical conductivity, this material must be combined with conductive materials to improve the energy storage efficiency. Carbon materials, particularly porous carbon, are ideal conductive substrates because of their high electrical conductivity, affordability, and ease of fabrication. This study demonstrates the synergistic effects of lignosulfonate/nanocarbon composites (LS/NC), in which heteroatom doping, high specific surface area, and quinone groups considerably enhance their electrochemical performance. Nanocarbon (NC) provides ion diffusion channels with low internal resistance and a large double-layer reaction area, promoting efficient electrolyte ion diffusion and transport. In addition, the introduction of oxygen and sulfur heteroatoms not only increases the material's hydrophilicity but also provides polar surfaces and accessible pseudocapacitive sites. Under acidic conditions, the LS/NC composite achieved a specific capacitance of 571 F g−1 at a discharge rate of 1 A g−1—approximately double that of NC alone (279 F g−1). These findings provide notable advancements in the development of efficient energy storage devices.

P. Riquelme-García, M. García-Rodríguez, J.X. Flores-Lasluisa et al.

Metal oxides of perovskite structure and SrMn1-xCoO3 type have been prepared by a sol-gel synthesis method and mixed with carbon black by ball milling for their use as electrocatalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) in a Zn-air battery. The composites obtained were characterized by different physicochemical and electrochemical techniques. The results of the characterization revealed the existence of two perovskite phases corresponding to Mn and Co as function of the Mn/Co ratio, whose interaction is related to a positive effect for the electrocatalytic activity. The presence of the M-O-C contribution was detected by XPS, which is related to an improvement in the catalytic activity against ORR/OER due to a better interaction and electron transfer between the perovskite and the carbon material. In addition, important differences were observed in the surface chemical species as a function of Mn/Co ratio and the higher the Co content in the composites the higher the amount of oxygen vacancies. The presence of oxygen vacancies is directly related to an improved OER activity; however, the presence of higher Mn content led to better catalytic results for ORR. The best electrocatalyst was studied in a Zn-air battery obtaining an excellent activity with a cyclability higher than 20 h, which is explained by the appropriate amounts of both Mn and Co.

Noor A. Mohammed, Abeer I. Alwared, Khitam Salim Shakhir et al.

This study was focused on the response surface methodology modeling (RSM) for the removal of Atrazine residue (ATZ) using nanocomposite. The FeNi3@SiO2@CuS nanocomposite was fabricated by co-precipitation and sol-gel methodologies, and their properties were studied by XRD, FTIR, VSM, and SEM techniques. The synthesis core-shell composite was used to degrade atrazine herbicide (ATZ) from synthetic wastewater. The efficiency of FeNi3@SiO2@CuS was calculated as a function of different input parameters (pH, ATZ concentration, catalyst concentration, H2O2 concentration, and reaction time by using a central composite design (CCD) adapted from response surface methodology. The CCD created a matrix of 60 runs of the experiment to look into how the five input elements interacted with one another. A reduced quadratic model was created using the findings and demonstrated good predictability of outcomes consistent with the research findings. Variance analysis (ANOVA) indicated that the chosen model was highly significant (p < 0.0001), and the coefficients of determination R2, adjusted R2, and predicted R2 were 0.9587, 0.9513, and 0.9380, respectively, confirming that the second-order regression model had been satisfactorily adjusted to obtained data. Furthermore, the findings provide validation that the degradation rate of ATZ adheres to a pseudo-first-order kinetic model, exhibiting an impressive R2 value surpassing 0.98. Through the use of a numerical optimization technique, a 95.24 % ATZ elimination was represented by the desirability of 81.12 %. This study suggests that sunlight, catalyst, and H2O2 together have a significant influence on ATZ degradation. Additionally, RSM was an appropriate process for optimizing the factors related to the elimination of ATZ by a solar-induced photocatalytic process.

Nicolò Zatta, Bernardo De Cesaro, Enrico Dal Cin et al.

Reduced-order electrothermal models play a key role in the design and control of lithium-ion cell stacks, calling for accurate model parameter calibration. This paper presents a complete electrical and thermal experimental characterization procedure for the coupled modeling of cylindrical lithium-ion cells in order to implement them in a prototype Formula SAE hybrid racing car. The main goal of the tests is to determine how the cell capacity varies with the temperature and the discharge current to predict the open-circuit voltage of the cell and its entropic component. A simple approach for the characterization of the battery equivalent electrical circuit and a two-step thermal characterization method are also shown. The investigations are carried out on four commercial 18650 NMC lithium cells. The model was shown to predict the battery voltage with an RMS error lower than 20 mV and the temperature with an RMS error equal to 0.5 °C. The authors hope that this manuscript can contribute to the development of standardized characterization techniques for such cells while offering experimental data and validated models that can be used by researchers and BMS designers in different applications.

Shuowen Bo, Fumin Tang, Hui Su et al.

Oxygen electrochemistry plays a key role in industrial hydrogen fuel production from water electrolysis, but the slow kinetics of anodic oxygen evolution reaction (OER) under large current density restricts the...

Lixing Xia, Yujing Zhang, Prof. Fuzhi Wang et al.

Abstract Quinone‐based aqueous redox flow batteries (RFBs) have drawn much attention due to their high safety, two‐electron involvement, rapid reaction kinetics, property tunability, and potentially low cost. RFBs operating in neutral solution feature a wide electrochemical window of around 2.5 V, which provides much more space for the design of redox‐active materials (RAMs) to realize a high voltage. However, it is still challenging to achieve low potential in the neutral condition for quinone‐based RAMs, owing to inherently pH‐dependent behaviors and deep LUMO (the lowest unoccupied molecular orbital) energy level. Herein, we report three low‐potential quinone‐based RAMs (1,4‐BDPAQCl2, 1,5‐BDPAQCl2, and 1,8‐BDPAQCl2) by bis‐dimethylamino substitution. The half‐wave potential of the quinones in 0.5 M KCl is approximately −0.55 to −0.57 V versus a normal hydrogen electrode. The low potential is ascribed to the introduced functional groups with two effects. First, the intramolecular hydrogen bonds formed between C=O and H−N can weaken the association between protons and dianion Q2−, resulting in a favorable distribution of products. Second, the functional groups can effectively increase the LUMO over 0.22 eV, compared with anthraquinone. Paired with Fe(glycine)2Cl2, the theoretical open‐circuit voltage of full RFBs is achieved at 1.27–1.29 V. We test full batteries using these quinones as negative RAMs at a lower concentration (0.1 M). The results show that 1,8‐BDPAQCl2 displays stability during 300 charge‐discharge cycles. In contrast, the other two quinones exhibit poor cycling stability due to side reactions. We further execute a higher concentration (0.4 M) for 1,8‐BDPAQCl2. The cycling stability of the quinone−iron RFBs is outstanding, with 0.048 % capacity decay per cycle and 0.88 % capacity decay per day. Our finding offers a feasible strategy to design low‐potential quinone molecules for the neutral RFBs.

Somayeh Molaei, Mohammad Ghadermazi, Nazanin Moeini

The surface of the Fe3O4 has been functionalized with 3-chloropropyltrimethoxysilane, which undergoes an SN2 substitution reaction of the chloro group with the nitrogen of ligand (creatinine), offering the Fe3O4@Creatinine. A new recyclable Ag attached Fe3O4 MNPs (Fe3O4 @Creatinine@Ag) has been produced through a post-synthetic method. FT-IR (Fourier Transforms Infrared), TGA (Thermogravimetric Analysis), XRD (X-ray Diffraction), EDS (Energy-Dispersive X-ray Spectroscopy) and VSM (Vibrating Sample Magnetometer) confirm the effectiveness of the performed chemical modification to synthesize the catalyst. This catalyst displays high catalytic performance in the synthesis of 5-substituted 1H-tetrazoles in water and the selective oxidation of sulfides. In the presence of nano- Fe3O4 @Creatinine@Ag as an efficient heterogeneous nano-catalyst, the corresponding 5-substituted 1H-tetrazoles and sulfoxide were afforded under the mild condition in good to excellent yields. A wide variety of sulfides furnished the corresponding sulfoxide with classical and ultrasonic methods. The results show that ultrasonic is an appropriate method for the oxidation of sulfides to the related sulfoxide. The catalyst can be separated by simple recovery and reused for several periods without any remarkable decrease in the catalysis activity and selectivity.In the synthesis of this catalyst, the environmentally friendly ligand is used to stabilize the eco-friendly active site on the desired support. What distinguishes this catalyst and this research is its high eco-friendliness in several respects. The structure of this catalyst and also, the reaction are based on green chemistry. At a relatively low temperature compared to the reported work, tetrazole derivatives are prepared in water solvent with good efficiency.

De Nora, which specialises in industrial electrochemistry, is working with the National Renewable Energy Laboratory (NREL), University of Oregon and Genomatica to develop a sustainable CO2-emissions-free biofuel technology.

Moran Balaish, J. Rupp

Classic chemical sensors integrated in phones, vehicles, and industrial plants monitor the levels of humidity or carbonaceous/oxygen species to track environmental changes. Current projections for the next two decades indicate the strong need to increase the ability of sensors to sense a wider range of chemicals for future electronics not only to continue monitoring environmental changes but also to ensure the health and safety of humans. To achieve this goal, more chemical sensing principles and hardware must be developed. Here, a proof‐of‐principle for the specific electrochemistry, material selection, and design of a Li‐garnet Li7La3Zr2O12 (LLZO)‐based electrochemical sensor is provided, targeting the highly corrosive environmental pollutant sulfur dioxide (SO2). This work extends the prime use of LLZO as a battery component as well as the range of trackable pollutants for potential future sensor‐noses. Novel composite sensing‐electrode designs using LLZO‐based porous scaffolds are employed to define a high number of reaction sites, and successfully track SO2 at the dangerous levels of 0–10 ppm with close‐to‐theoretical SO2 sensitivity. The insights on the sensing electrochemistry, phase stability and sensing electrode/Li+ electrolyte structures provide first guidelines for future Li‐garnet sensors to monitor a wider range of environmental pollutants and toxins.

Derek Richard, Yu-Chao Huang, Carlos G. Morales‐Guio

Andrew E Eisenhart, T. Beck

The need for environmentally friendly nonaqueous solvents in electrochemistry and other fields has motivated recent research into the molecular-level solvation structure, thermodynamics, and dynamics of candidate organic liquids. In this paper, we present the results of quantum density functional theory simulations of glycerol carbonate (GC), a molecule that has been proposed as a solvent for green industrial chemistry, nonaqueous alternatives for biocatalytic reactions, and liquid media in energy storage devices. We investigate the structure and dynamics of both the pure GC liquid and electrolyte solutions containing KF and KCl ion pairs. These simulations reveal the importance of hydrogen bonding that controls the structural and dynamic behavior of the pure liquid and ion association in the electrolyte solutions. The results illustrate the difficulties associated with classical modeling of complex organic solvents. The simulations lead to a better understanding of the underlying mechanisms behind the previously observed peculiar ion-specific behavior in GC electrolyte solutions.

Ningbo Xu, Jingwen Shi, Gaopan Liu et al.

The construction of Solid Electrolyte Interface (SEI) film in Li-ion batteries with functional electrolyte additives is able to passivate the active material surface and inhibit the decomposition of the electrolyte continuously. In addition, safety issue is also an important factor restricting the large scale application of present lithium-ion batteries. Therefore, the additives for film-forming and safety enhancement are a class of cost-effective components that promote the application and development of batteries. Fluorine is a kind of “bipolar” element, which has strong electronegativity and weak polarity. Fluorine-containing electrolyte additives have excellent kinetic reactivity, which can preferentially generate stable SEI films and uniform Cathode-Electrolyte Interface (CEI) films to effectively improve the electrochemical performance of the batteries. Meanwhile, fluorine-containing electrolyte additives can also be used as flame-retardants to improve safety performance. In this review, we summarize the research status of fluorine-containing additives in recent years and elaborate its reaction mechanisms of improving battery performance. Finally, a personal perspective on the future of the development of fluorine-containing additives is presented.

Xinyao Luo, Hangfu Yang, Nengjun Yu et al.

The structure, magnetic, and the magnetocaloric effecton the La0.7-xEuxSr0.3MnO3sample prepared by the solid-state reaction method had been investigated. The structure data obtained from X-ray powder diffraction and Rietveld refinement analysis show that all these samples have single-phase and a rhombohedra structure with R-3c space group. With the substitution of the Eu3+ content, the volume of unit cells and Mn-O-Mn bond angle increase monotonically as well as the Curie temperature TC, which is caused by the weakening of the double exchange interaction. A magnetic entropy change (-ΔSM)max of 2.21 J kg-1K-1 is obtained under a magnetic field change of 20 kOe for La0.66Eu0.04Sr0.3MnO3 sample. All samples exhibit the FM-PM phase transition with a second-order nature. In the electrochemistry corrosion experiment for the sample, the mass loss rate of the sample is small, so the material possesses optimal anticorrosion performance. The lattice structure and the Curie temperature of the material can be manipulated to some extend with Eu3+ substitution, which provides a method for magnetic refrigeration in an electrolyte solution environment.

Lin-jie Zhang, Hai-bo Zhang, X. Lei et al.

Abstract MBLS10A-200 magnesium-lithium (Mg-Li) alloy is a novel ultralight material, with the density, tensile strength and elongation rate of 1.5 g/cm3, 160 MPa and 60%, respectively. At present, the material is increasingly widely applied in structures with complex shapes of various fields such as aeronautics, astronautics and electronic engineering. At present, the industrial circle has put forward increasingly urgent demand for the welding technique of MBLS10A-200 alloy and the protection technology for corrosion resistance of the welded joints of the alloy. However, related research is rarely reported. Laser welding of MBLS10A-200 Mg-Li alloy with 5 mm in thickness was studied to further obtain the butt joint, with the elongation rate of about 54% and the same strength as base metal (BM). Moreover, the corrosion resistance of laser welded joint was detected by using electrochemistry method. During the experiment, it can be found that the corrosion resistance of metals in the welded seam zone (WSZ) was far higher than that of the BM. The corrosion current density of metals in WSZ was about 10-5 A/cm2, which declined by two orders of magnitude compared with BMs which were about 10-7 A/cm2 and the charge transfer resistance of welded seam zone increased by 4.8 times compared with BMs.

R. Ganigué, Pieter Naert, P. Candry et al.

Valeric acid and its ester derivatives are chemical compounds with a high industrial interest. Here we report a new approach to produce them from crude glycerol, by combining propionic acid fermentation with chain elongation. Propionic acid was produced by Propionibacterium acidipropionici (8.49 ± 1.40 g·L-1). In the subsequent mixed population chain elongation, valeric acid was the dominant product (5.3 ± 0.69 g·L-1) of the chain elongation process. Residual glycerol negatively impacted the selectivity of mixed culture chain elongation towards valeric acid, whereas this was unaffected when Clostridium kluyveri was used as bio-catalyst. Valeric acid could be selectively isolated and upgraded to ethyl valerate by using dodecane as extractant and medium for esterification, whereas shorter-chain carboxylic acids could be recovered by using a 10 wt% solution of trioctylphosphine oxide (TOPO) in dodecane. Overall, our work shows that the combined fermentation, electrochemistry and homogeneous catalysis enables fine chemical production from side streams.

HaiTao Yan, SenSen Xin, Yong Yang et al.

The microstructure and corrosion behavior of 2205 duplex stainless steel (DSS) welds were investigated by optical microscopy (OM), scanning electronic microscopy (SEM) and electrochemical measurements. The ferrite (δ) phase content increases slightly from the base metal (BM) zone, to the heat affected zone (HAZ) to the weld metal (WM) of the welded joint. HAZ shows a very weak sensitization that was effectively detected by the double-loop electrochemical potentiokinetic reactivation (DL-EPR) test with an H2SO4 + HCl mixed solution. In hot artificial seawater, the pitting corrosion resistance, passivation and repassivation abilities decrease gradually from BM, to WM to HAZ. Weak sensitization plays a dominant role in the pitting corrosion of HAZ even though the degree of sensitization (DOS) is very low. BM and WM do not show intergranular corrosion (IGC) susceptibility and the difference in the pitting resistance between these two zones is small. The pitting corrosion resistance of the three weld zones was discussed in detail.

Lan-xiang Sun, Haibin Yu, Z. Cong et al.