Hasil untuk "Industrial electrochemistry"

José R. Rodríguez, S. Bernet, Bin Wu et al.

U. Schröder, F. Harnisch, L. T. Angenent

Dayoung Kim, Cheolhwan Song, Oh B. Chae

Recent advancements in lithium-metal-based battery technology have garnered significant attention, driven by the increasing demand for high-energy storage devices such as electric vehicles (EVs). Lithium (Li) metal has long been considered an ideal negative electrode due to its high theoretical specific capacity (3860 mAh g⁻¹) and low redox potential. However, the commercialization of Li-metal batteries (LMBs) faces significant challenges, primarily related to the safety and cyclability of the negative electrodes. The formation of lithium dendrites and uneven solid electrolyte interphases, along with volumetric expansion during cycling, severely hinder the commercial viability of LMBs. Among the various strategies developed to overcome these challenges, the introduction of artificial protective layers and the structural engineering of current collectors have emerged as highly promising approaches. These techniques are critical for regulating Li deposition behavior, mitigating dendrite growth, and enhancing interfacial and mechanical stability. This review summarizes the current state of Li-negative electrodes and introduces methods of enhancing their performance using a protective layer and current collector design.

Patrycja Koscielniak, Maria Sawicka, Ilya Sterin et al.

Developing new and improving existing systems for controlled drug release is one of the top tasks of biomaterials science nowadays. The current work aims to develop an efficiently controlled doxorubicin release system based on composite hydrogel formed by polyacrylic acid p(AA) cross-linked by N,N’-bis(acryloyl)cystamine (BAC). The formed p(AA-BAC) microgel provides a dual function as a pH-sensitive doxorubicin holding carrier as well as an immobilization matrix for covalent bonding of gold nanoparticles (AuNPs) via sulfur groups of cystamine derivative cross-linker. The immobilized AuNPs are characterized by nanozyme (glucose oxidase-like) activity able to generate the local pH decrease via gluconic acid production in the presence of glucose as a trigger. The resulting local pH decrease provides protonation of carboxylic groups of the p(AA-BAC) matrix resulting in diminished electrostatic attraction between the carrier and the positively charged payload, thus causing its release from the microgels. The structural and morphological characterization of the proposed p(AA-BAC)-AuNPs composite microgel was performed by SEM, AFM, TEM, FTIR, and other techniques. The kinetics of the triggered release of the self-fluorescent doxorubicin was tested by fluorimetry combined with confocal fluorescent analysis. It was demonstrated that the proposed composite p(AA-BAC)-AuNPs microgel could be used as a promising smart release system for releasing a positively charged payload in response to a locally elevated glucose level.

William Yourey, Kayla Nong, Bhanu Babaiahgari

With the goal of increasing energy density in lithium–ion cells, new active materials continue to be developed and evaluated. Similarly, in commercial lithium–ion cells, inert materials present in manufactured cells should also be evaluated. The impact of the thickness of inert materials on EV-sized lithium–ion cells was evaluated. The impact of the thicknesses of the positive current collector, negative current collector, separator, and aluminum laminate package on cell properties is presented. The impact of these materials varies greatly over different cell designs, with one of the largest impacts being from a decrease in separator material thickness, especially in cells with a high number of electrode pairs, specifically, cells with a larger thickness or cells with low-capacity loadings. For high-capacity positive electrode loading, a decrease in separator thickness from 16 to 8 microns results in an increase in stack volumetric energy density from 502 to 531 Wh/L or an increase of 5.7%.

Daniela Galatro, Manav Shroff, Cristina H. Amon

This work presents an adaptive transfer learning approach for predicting the aging of lithium-ion batteries (LiBs) in electric vehicles using capacity fade as the metric for the battery state of health. The proposed approach includes a similarity-based and adaptive strategy in which selected data from an original dataset are transferred to a clean dataset based on the combined/weighted similarity contribution of feature and stress factor similarities and times series similarities. Transfer learning (TL) is then performed by pre-training a model with clean data, with frozen weights and biases to the hidden layer. At the same time, weights and biases toward the output node are recalculated with the target data. The error reduction lies between −0.4% and −8.3% for 20 computational experiments, attesting to the effectiveness and robustness of our adaptive TL approach. Considerations for data structure and representation learning are presented, as well as a workflow to enhance the application of transfer learning for predicting aging in LiBs.

Yu Shi, Haicheng Xie, Xinhong Wang et al.

Against the backdrop of automobile electrification, an increasing number of battery-swapping stations for electric vehicles have been launched to address the issue of slow battery charging under cold temperature conditions. However, due to the separation of the discharging and charging processes for lithium-ion batteries (LIBs) at swapping stations, and the circulation of batteries across different vehicles and stations, the operating data become fragmented, making it difficult to accurately identify the battery state-of-health (SOH). This study proposes a BiLSTM-Transformer framework that extracts the Constant Voltage Time (CVT) feature using only charging data, enabling the precise estimation of battery capacity degradation. Validation experiments conducted on battery samples under different operating temperatures showed that the model achieved a normalized RMSE of less than 1.6%. In ideal conditions, the normalized RMSE of the estimation reached as low as 0.11%. This model enables SOH estimation without relying on discharge data, contributing to the efficient and safe operation of battery swapping stations.

Abdul G. Al Lafi, Jamal Alabdullah, Mohammed Amer Mougrabya et al.

Nano manganese dioxide (NMO) has conquered many important research and application areas but its widespread utilization in adsorption is progressively impacted by the difficulties encountered in solid–liquid separation. Hence, fabrication of polymer/NMO composites has been suggested. This paper devoted to investigate the effects of polymer matrix on the structural and morphological characteristics of polymer/NMO composites using sulfonated poly (ether ether ketone) (SPEEK) having a variety of structures and surface properties as templates. Three distinct types of NMO morphologies were observed namely, nano particle, flower like and rod like nano structures, while metallic Mn was precipitated in other samples. The adsorption capacities decreased from 10 mg g−1 to zero with increasing the IEC of composite based on helium irradiated SPEEK/NMO. Similarly, the adsorption capacities decreased from 16 mg g−1 to zero of composite based on proton irradiated SPEEK/NMO. These were accompanied with the disappearance of the flower like nano structure of NMO in the composite. The structure and morphology of loaded NMO is sensitive to the structure and surface properties of the polymers and this could explain the difference in adsorption properties of polymer/NMO composites, and help in the design of selective adsorbents.

Jing Sun, Qiang Guo, Wanqing Dai et al.

The development of conductive coatings has significant implications for microelectronics and electrochemistry. However, conductive coatings may exhibit different electrochemical properties when prepared on different substrate materials. This research explores the comparative performance of graphene, graphene oxide (GO), and silver nanoparticle (Ag NP) composites as conductive coatings on diverse substrate materials, including polydimethylsiloxane (PDMS), polymethyl methacrylate (PMMA), and glass. The study employed various preparation methods, such as mixing conductive materials with substrate materials and preparing copolymer composite materials. The conductive coating approach was found to be the most straightforward and convenient, with broader development prospects and fewer restrictive conditions. The results indicate that the distinct surface characteristics of the substrate materials influence the conductive properties of coating materials. Consequently, results show that graphene exhibits the highest conductivity on all three substrates, while GO is more conductive than Ag NPs on PMMA and PDMS but less conductive than Ag NPs on glass. That offers valuable insights into the selection of substrate materials and coating materials for the preparation of conductive materials.

Sergi Garcia-Segura, Xiaolei Qu, Pedro J. J. Alvarez et al.

Based upon an international workshop, this perspective evaluates how nano-scale pore structures and unique properties that emerge at nano- and sub-nano-size domains could improve the energy efficiency and selectivity of electroseparation or electrocatalytic processes for treating potable or waste waters. An Eisenhower matrix prioritizes the urgency or impact of addressing potential barriers or opportunities. There has been little optimization of electrochemical reactors to increase mass transport rates of pollutants to, from, and within electrode surfaces, which become important as nano-porous structures are engineered into electrodes. A “trap-and-zap” strategy is discussed wherein nanostructures (pores, sieves, and crystal facets) are employed to allow localized concentration of target pollutants relative to background solutes (i.e., localized pollutant trapping). The trapping is followed by localized production of tailored reactive oxygen species to selectively degrade the target pollutant (i.e., localized zapping). Frequently overlooked in much of the electrode-material development literature, nano-scale structures touted to be highly “reactive” towards target pollutants may also be the most susceptible to material degradation (i.e., aging) or fouling by mineral scales that form due to localized pH changes. A need exists to study localized pH and electric-field related aging or fouling mechanisms and strategies to limit or reverse adverse outcomes from aging or fouling. This perspective provides examples of the trends and identifies promising directions to advance nano-materials and engineering principles to exploit the growing need for near chemical-free, advanced oxidation/reduction or separation processes enabled through electrochemistry.

V. Ganesh, T.H. Al Abdulaal, S.G.S. Al-Amri et al.

The synthesis of pure and different concentrations of Cr-doped (1, 2.5, 5, 7, 10 wt%) lead iodide (PbI2) nanosheets was successfully achieved using a low-cost and simple microwave method. The prepared Cr-doped PbI2 nanostructures were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), FT-Raman, diffuse reflectance, dielectric, and gamma absorption analysis. The structural investigation confirmed the hexagonal phase of the proposed nanostructures without the impurity phase. Morphological studies proved that the undoped PbI2 nanosheet has a size of less than 100 nm, and the size of the prepared Cr-doped PbI2 samples was around 50-60 nm. FT-Raman and optical analysis investigated the doping effects on the pure PbI2 matrix through the slight shifting of characteristics peaks and the energy bandgaps’ variations. The optical bandgap values of pure PbI2 and Cr-doped PbI2 samples were estimated to be ranged from 2.0 eV to 2.2 eV. The obtained values of the dielectric constant were increased from 20 to 27 due to introducing the Cr- ions into the host PbI2 matrix. Together with Cr- dopants, the linear coefficient of Gamma absorption illustrates improvements. To conclude, due to the enhancement in structural morphology, optical, and radiation properties of the synthesized Cr-doped PbI2 nanostructures, those proposed nanosheets potentially are remarkable candidates for various applications including optoelectronics and radiation detectors.

Jun Cheng, Hongqiang Zhang, Deping Li et al.

Due to the intrinsically high ionic conductivity and good interfacial stability towards lithium, garnet-type solid electrolytes are usually introduced into polymer electrolytes as fillers to prepare polymer/garnet composite electrolytes, which can improve the ionic conductivity and enhance the mechanical strength to suppress Li dendrites. However, the surface Li₂CO₃ and/or LiOH passive layers which form when garnet is exposed to the air greatly reduce the enhancement effect of garnet on the composite electrolyte. Furthermore, compared with micro-size particles, nano-size garnet fillers exhibit a better effect on enhancing the performance of composite solid electrolytes. Nevertheless, inferior organic/inorganic interphase compatibility and high specific surface energy of nanofillers inevitably cause agglomeration, which severely hinders the effect of nanoparticles for promoting composite solid electrolytes. Herein, a cost-effective amphipathic 3-Aminopropyltriethoxysilane coupling agent is introduced to modify garnet fillers, which effectively expands the air stability of garnet and greatly improves the dispersion of garnet fillers in the polymer matrix. The well-dispersed garnet filler/polymer interface is intimate through the bridging effect of the silane coupling agent, resulting in boosted ionic conductivity (0.72 × 10⁻⁴ S/cm at room temperature) of the composite electrolyte, enhanced stability against lithium dendrites (critical current density > 0.5 mA/cm²), and prolonged cycling life of LFP/Li full cells.

Michael Theiler, Christian Endisch, Meinert Lewerenz

Float currents are steady-state self-discharge currents after a transient phase—caused by anode overhang, polarization, etc.—is accomplished. The float current is measured in this study with a standard test bench for five 18650 cells (Samsung 25R) at potentiostatic conditions while the temperature is changed in 5 K steps from 5 °C to 60 °C. The entire test is performed in about 100 days resulting in 12 measurement points per cell potential for an Arrhenius representation. The float current follows the Arrhenius law with an activation energy of about 60 kJ/mol. The capacity loss measured at reference condition shows a high correlation to the results of float currents analysis. In contrast to classical calendar aging tests, the performed float current analysis enables determining the aging rate with high precision down to at least 10 °C. Returning from higher temperatures to 30 °C reference temperature shows reducing float currents at 30 °C for increasing temperature steps that may originate from an hysteresis effect that has to be investigated in future publications.

Karolina Kowalewska, Karolina Sipa, Andrzej Leniart et al.

Abstract The interfacial polymerization of nylon-6,6 is studied at the polarized liquid–liquid interface. The optimal conditions (concentration of reagents in a biphasic system, pH of the water phase, voltammetric cycling) are used to modify the interface, supported by a microcapillary, giving a platform with molecular sieving properties.

J. Feliu

J. Lipkowski

A. W. Hassel

With last year’s Nobel Prize for the development of lithium ion batteries, electrochemistry as a discipline was well recognized by a broader scientific community and the society itself. This is however only one aspect of the importance of electrochemistry for solving our energy problems. Lots of attempts are presently made to tackle the global climate challenge. There is a large number of attempts such as avoiding CO2 emission by using regenerative energy (batteries required), reducing CO2 emission by changes in the process, for example, to fuel cells with higher efficiency (cheap and efficient electrocatalysts required), reuse of produced CO2 to generate fuels or produce compounds which are presently made from natural gas or oil. Also the steps into an extended use of hydrogen as energy carrier require electrochemical processes during production and use. A principal advantage of electrochemistry is that it is directly linking chemical reactions and electrical voltage/current. This allows driving chemical reactions with electrical energy on one side but also yield electrical signals from chemical reactions through sensors which can be directly processed further electronically. For sure the importance of electrochemistry will grow further and will pervade our daily life. Let us have a look into why and how this is happening and where are the future tasks for us as electrochemists or scientist entering this field.

G. Inzelt

We may agree with the saying which is attributable to Niels Bohr who said: “It is difficult to make predictions, especially about the future.” Nevertheless, the past can give ideas in this respect and the present circumstances set the course. However, the great breakthroughs cannot be predicted. Without any exaggeration, we may declare that electrochemistry has played, plays, and will play an important role in the scientific and technological advancement, and consequently the quality of life of the people. We cannot imagine the everyday life without electricity. We have had electric current for 220 years since Volta constructed his pile. The year 1800 was the birth of electrochemistry because beside the production of the first electrochemical power source, electrolysis experiments were also executed. Nowadays, I see some problem concerning the desired ratio between the fundamental and applied research. I agree that people are happy with small batteries in their cellular phone or in their pacemaker. It is also good that the research is directed to pollution control. The easy monitoring of glucose level in blood is also a real success. These are important achievements, and the production of things that make the life better is the ultimate goal of the science. Unfortunately, it is often forgotten that all these successes have started decades or even centuries earlier when a researcher discovered a new material or a novel property of matter. Afterwards, during an extended period of time, others clarified the theoretical basis which gave a new impetus, and many discoveries eventually lead to the new product which usually will be improved again and again for decades. The problem is that if the fundamental research would not be financed or financed properly, the development of science and consequently that of the technology will stop or at least will slow down. The decision makers want an immediate success for the money of the taxpayers. The applied research and especially the innovation phase needing the capital also for buildings and machines want orders of magnitude higher money than the grant for some thousand researchers at the universities and institutes. The support of the basic research is not a wasted money, and it underlies the future. I would like to draw the attention to another important point: it is the proper education. The wellprepared and competent researchers are essential for the progress in the future. It is true in all cases, i.e., independently whether we are talking about basic or applied research, or even serendipity. The curiosity of scientists, the intuition, or the fantasy are of the utmost importance, however, the researchers need a solid knowledge, as well. “They have made up the solution of something they knew about, said Poirot.”

S. Pyun

U. Schröder

Electrochemistry is a niche subject. We get this impression when looking into the curricula of chemistry courses—at least at German universities. They contain electrochemistry usually as a minor aspect of physical or general chemistry in undergraduate courses—mostly confined to electrolyte concepts and electrochemical equilibria; advanced electrochemistry courses are scarce and are generally tied to graduate programs at departments with active electrochemical research. Thereby, chairs with an explicit electrochemistry denomination are the exception, and the majority of active groups and chairs operate under the flag of physical, analytical, technical, inorganic, or organic chemistry—or related engineering subjects. The scientific output of the electrochemical community does not reflect this apparent niche existence. Thus, a SciVal analysis (from May 12, 2020) for the years 2014–2019 shows that the international publication output in electrochemistry of 74,320 publications is more than half as high as the number of publications in inorganic chemistry (134,165), one of the main subjects in chemistry. This underlines the creativeness of a vital community. It is obvious and beyond discussion of this article that electrochemistry has become a core element for the research and development in regenerative energy conversion and storage. This trend is reflected in the strong increase in the relative share of fuel cell and battery-related publications over the past 20 years within the electrochemistry field (See Fig. 1). The trend underlines the effects of a focused and strongly increased research funding in this area, which has a significant impact on the publication activity. Looking at fuel cells, the growth trends seem enduring, although the focus of research funding has recently been shifted towards batteries. The current political and social-economic efforts to realize electro-mobility have pushed electrochemistry forward—and into the public and general scientific awareness. This is a unique chance to sustainably strengthen the electrochemical research landscape, e.g., by establishing new research groups and university chairs. Yet, in this development, the rich diversity of electrochemistry should not be sacrificed. Electrochemistry is much broader than battery research. It bridges somany disciplines—from physical chemistry, organic, and inorganic chemistry, as well as green chemistry, to even biology and biochemistry, making electrochemistry an inherently interfacial science, rather than a stand-alone discipline. This explains why we find electrochemical research in so different science and engineering departments—and why electrochemistry should always have its home in these disciplines. I would even go as far as to say that the self-conception of electrochemistry should always be to serve as a connector of sciences. I see this inherent connection in my core research field—microbial electrochemistry and technology. Here, electrochemistry links biology, biochemistry, physical chemistry, materials science, biotechnology, and environmental technology—and even biogeochemistry. The resulting multidisciplinarity creates a fascination that I have missed for a long time in electrochemistry and that attracts many new, young researchers. Yet, to exploit the full potential of a multifaceted electrochemistry, a huge gap needs to be closed—the deficient and often rudimentary electrochemical education. Thus, as much as electrochemistry connects to so many disciplines is part of these disciplines, it should also become part of their education. * Uwe Schröder uwe.schroeder@tu-braunschweig.de