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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 181 records · Page 10
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Non-contact electrochemical evaluation of biofilms

Abstract Here, we demonstrate a non-contact technique for electrochemical evaluation of biofilms on surfaces in relation to corrosion. Electrochemical impedance spectrometry was employed, incorporating flat patterned electrodes positioned over the surfaces of aluminum and glass with and without biofilms. Signal communication from the working electrode to the counter electrode followed electric field lines passing tangentially through the biofilms. Electrochemical impedance parameters that were evaluated included complex impedance, phase angle, imaginary (out of phase) conductivity and Cole–Cole plots with a corresponding equivalent circuit. Changes in the impedance properties due to the presence of biofilms were monitored and correlated through microbiological, chemical and electrochemical assays. Impedance parameters associated with microbial activity correlated with biofilms on aluminum and glass surfaces. This technical approach provides impedance information about the biofilm without the signal traveling through the underlying conductive media or disrupting the biofilm. In this way, biological contributions to surface fouling can be evaluated with minimal contribution from the inorganic surface under the biofilm. In addition, this technique can be used to monitor biofilms on electrochemically inert surfaces as well as electrically conductive surfaces. Graphic abstract

Turick, Charles E. (ORCID:0000000307815846)↗
DOE OSTI2022

Electrochemical, thermodynamic, and physical properties of tetradecyltrihexylphosphonium ([P 6,6, 6,14 ] + ) and methyl-propyl piperidinium containing ionic liquids and their propylene carbonate solutions

Here, the viscosity, conductivity, electrochemical window and related thermodynamic properties such as excess volume and dynamic viscosity deviation of two phosphonium ionic liquids were measured and calculated for “as-supplied” and dried neat liquids and also v/v mixtures of 99/1, 95/5, 90/10, 75/25, and 50/50 of the ionic liquids with propylene carbonate (PC). Tetradecyltrihexylphosphonium dicyanamide ([P 6,6,6,14 ] + dicyanamide), Cyphos 105, and tetradecyltrihexylphosphonium bis(trifluororomethanesulfonyl)imide (called bistriflimide) ([P 6,6,6,14 ] + bistriflimide), Cyphos 109, ionic liquids were studied. Generally speaking, there were slight differences in the measured properties of the wet and dried IL solutions which were reflected in differences if the calculated properties. The measured and calculated properties were compared with those collected and derived from a piperidinium-based ionic liquid, methyl-propyl piperidinium bistriflimide. Arrhenius plots for both the viscosity and conductivity were linear, with the linearity of the Litovitz plots being slightly higher. The viscosity and conductivity of the phosphonium solutions yielded Walden Plots that differed from Walden plots of piperidinium solutions and other ionic liquid solutions. For the phosphonium based ionic liquids, the ionicity was found to increase with increasing dilution in propylene carbonate. The electrochemical windows of the ionic liquids were determined as a function of the concentration of the ionic liquid present in the solution. The size of the window generally initially decreased and then increased with the addition of PC for the [P 6,6,6,14 ] + dicyanamide ionic liquid increasing from 3.4 V in the 95/5 v/v (volume Cyphos 105) to volume of PC solvent) to 3.7 in the 50/50 dried IL case. The electrochemical windows of the dried liquids were slightly larger 3.5 V for the 95/5 v/v and 4.2 V for the 50/50 v/v Cyphos 105/PC solutions. The electrochemical window was larger and the conductivity was higher for the piperidinium IL solutions, but since the ionicity increases with dilution, the phosphonium based IL solutions may prove favorable for processes such as electrochemical reduction.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2025

Microelectrode Arrays for Electrochemical Cycling of Individual Battery Particles

The electrochemical characterization of battery materials is usually performed on porous electrodes containing conductive additives, binders, and ensembles of redox-active particles at densities as high as 10 15 cm –3 . These complex structures often obscure individual battery particles’ intrinsic properties, hindering insights into the fundamentals of battery electrochemistry. To address this challenge, we developed microelectrode arrays to enable the charge and discharge of individual battery particles in liquid electrolytes. In this Methods and Protocols paper, we describe the fabrication of the microelectrode array chips, the assembly of particles onto microelectrodes, and the different types of electrochemical techniques that can be used, including galvanostatic cycling, cyclic voltammetry, potentiostatic intermittent titration, and electrochemical impedance spectroscopy. We use micron-sized lithium cobalt oxide as a model system to showcase the reliability and versatility of single-particle electrochemical experiments enabled by our microelectrode array. In conclusion, we aim to provide a detailed description to promote future uses of microelectrode arrays in fundamental research of batteries and other electrochemical systems.

25 ENERGY STORAGE↗
DOE OSTI2025

Probing Surface/Bulk Structural Chemistry of Key Components of Solid Oxide Electrochemical Cells with In Situ / Operando Raman Spectroscopy

The remarkable attributes of solid oxide electrochemical cell technology (e.g., energy efficiency, low cost, scalability, low emissions, and operational flexibility, etc.) drive the wider adoption of electrochemical conversion routes for sustainability. It is critical for the codevelopment of solid oxide cell materials and processes to establish the mechanistic understanding of the underlying chemical phenomena at the molecular level. Herein, we summarize the advancements in Raman spectroscopy that provide structural/molecular information on electrode/electrolyte materials typically used in solid oxide cells for energy conversion. In particular, we discuss the multifactorial environment induced chemical processes that govern the performance and longevity of solid oxide electrochemical devices. The in situ/operando Raman spectroscopic investigations on the electrode/electrolyte materials reported in the literature are summarized with the emphasis on identification of key material properties that control the functional aspects of the solid oxide cells. The molecular level understanding of the electrochemical processes will allow advancement of the rational design of electrochemical materials for process level deployment of solid oxide cell technology.

Electrodes↗
DOE OSTI2024

Interplay between Catalyst Corrosion and Homogeneous Reactive Oxygen Species in Electrochemical Ozone Production

In this study, electrochemical ozone production (EOP), a six-electron water oxidation reaction, offers promising avenues for creating value-added oxidants and disinfectants. However, progress in this field is slowed by a dearth of understanding of fundamental reaction mechanisms. In this work, we combine experimental electrochemistry, spectroscopic detection of reactive oxygen species (ROS), oxygen-anion chemical ionization mass spectrometry, and computational quantum chemistry calculations to determine a plausible reaction mechanism on nickel- and antimony-doped tin oxide (Ni/Sb–SnO 2 , NATO), one of the most selective EOP catalysts. Antimony doping is shown to increase the conductivity of the catalyst, leading to improved electrochemical performance. Spectroscopic analysis and electrochemical experiments combined with quantum chemistry predictions reveal that hydrogen peroxide (H 2 O 2 ) is a critical reaction intermediate. We propose that leached Ni 4+ cations catalyze hydrogen peroxide into solution phase hydroperoxyl radicals ( • OOH); these radicals are subsequently oxidized to ozone. Isotopic product analysis shows that ozone is generated catalytically from water and corrosively from the catalyst oxide lattice without regeneration of lattice oxygens. Further quantum chemistry calculations and thermodynamic analysis suggest that the electrochemical corrosion of tin oxide itself might generate hydrogen peroxide, which is then catalyzed to ozone. The proposed pathways explain both the roles of dopants in NATO and its lack of stability. Our study interrogates the possibility that instability and electrochemical activity are intrinsically linked through the formation of ROS. In doing so, we provide the first mechanism for EOP that is consistent with computational and experimental results and highlight the central challenge of instability as a target for future research efforts.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2020

Electrolyte Engineering for Efficient Electrochemical Nitrate Reduction to Ammonia on a Titanium Electrode

Nitrates from agricultural runoff and industrial waste streams are a notorious waste product and hazardous pollutant. Traditional electrochemical water remediation approaches aim to solve this problem by converting nitrates to environmentally benign N 2 while minimizing the production of environmentally hazardous side products such as ammonia and nitrous oxide in a process known as “denitrification”. We modify this concept and outline an opportunity to optimize the conversion of nitrates into ammonia, which is also a key commodity product used as a fertilizer, potential fuel, and chemical precursor. The electrochemical conversion of nitrates to ammonia recycles the fixed nitrogen and offers an appealing and supplementary alternative to the energy- and resource-intensive Haber-Bosch process. In this study, we investigated the effect of varying electrochemical conditions (pH, nitrate concentration, and applied potential) on the selective reduction of nitrate to ammonia at a titanium cathode. We observed that high concentrations of both protons and nitrate ions are needed to achieve high selectivity, reaching a peak of 82% Faradaic efficiency to ammonia at an applied potential of -1 V versus RHE and a partial current density to NH 3 of -22 mA/cm 2 , using 0.4 M [NO 3 – ] at pH ~0.77. The Ti electrode, as a poor hydrogen evolution catalyst with notable corrosion resistance, provides a large window of operating conditions to achieve high selectivity in the reduction of nitrate anions. Stability of the system was evaluated, and we found a high Faradaic efficiency throughout the course of an 8 h experiment. After electrochemical testing, titanium hydride was observed at the cathode surface. We also show a preliminary technoeconomic study, indicating that it may be feasible to employ an electrochemical strategy for the production of ammonium nitrate.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2023

Hydration of a Side-Chain-Free n-Type Semiconducting Ladder Polymer Driven by Electrochemical Doping

Here, we study the organic electrochemical transistors (OECTs) performance of the ladder polymer, poly(benzimidazobenzophenanthroline) (BBL) in an attempt to better understand how an apparently hydrophobic side-chain-free polymer is able to operate as an OECT with favorable redox kinetics in an aqueous environment. We examine two BBLs of different molecular masses from different sources. Both BBLs show significant film swelling during the initial reduction step. By combining electrochemical quartz crystal microbalance (eQCM) gravimetry, in-operando atomic force microscopy (AFM), and both ex-situ and in-operando grazing incidence wide-angle x-ray scattering (GIWAXS), we provide a detailed structural picture of the electrochemical charge injection process in BBL in the absence of any hydrophilic side-chains. Compared with ex-situ measurements, inoperando GIWAXS shows both more swelling upon electrochemical doping than has previously been recognized, and less contraction upon dedoping. The data show that BBL films undergo an irreversible hydration driven by the initial electrochemical doping cycle with significant water retention and lamellar expansion that persists across subsequent oxidation/reduction cycles. This swelling creates a hydrophilic environment that facilitates the subsequent fast hydrated ion transport in the absence of the hydrophilic side-chains used in many other polymer systems. Due to its rigid ladder backbone and absence of hydrophilic side-chains, the primary BBL water uptake does not significantly degrade the crystalline order, and the original dehydrated, unswelled state can be recovered after drying. The combination of doping induced hydrophilicity and robust crystalline order leads to efficient ionic transport and good stability.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2022

The effect of residual palladium on the performance of organic electrochemical transistors

Organic electrochemical transistors are a promising technology for bioelectronic devices, with applications in neuromorphic computing and healthcare. The active component enabling an organic electrochemical transistor is the organic mixed ionic-electronic conductor whose optimization is critical for realizing high-performing devices. In this study, the influence of purity and molecular weight is examined for a p-type polythiophene and an n-type naphthalene diimide-based polymer in improving the performance and safety of organic electrochemical transistors. Our preparative GPC purification reduced the Pd content in the polymers and improved their organic electrochemical transistor mobility by ~60% and 80% for the p- and n-type materials, respectively. These findings demonstrate the paramount importance of removing residual Pd, which was concluded to be more critical than optimization of a polymer’s molecular weight, to improve organic electrochemical transistor performance and that there is readily available improvement in performance and stability of many of the reported organic mixed ionic-electronic conductors.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2022

In situ electrochemical recomposition of decomposed redox-active species in aqueous organic flow batteries

Aqueous organic redox flow batteries (AORFBs) offer a safe and potentially inexpensive solution to the problem of storing massive amounts of electricity produced from intermittent renewables. However, molecular decomposition is the major barrier preventing AORFBs from being commercialized. Structural modifications can improve molecular stability at the expense of increased synthetic cost and molecular weight. Utilizing 2,6-dihydroxy-anthraquinone (DHAQ), without further structural modification, we demonstrate that electrochemical regeneration could be a viable route to achieve low-cost, long-lifetime AORFBs. In situ (online) NMR and EPR and complementary electrochemical analyses reveal that decomposition compounds i.e., 2,6-dihydroxy-anthrone (DHA) and its tautomer, 2,6-dihydroxy-anthranol (DHAL), can be converted back to DHAQ in two steps: first DHA(L) 2- are oxidized to the dimer (DHA) 2 4- at - 0.32 V vs. SHE by one-electron transfer; subsequently, the (DHA) 2 4- is oxidized to DHAQ 2- at +0.57 V vs. SHE by three-electron transfer. Electrochemical regeneration rejuvenates not only DHAQ 2- , but also the positive electrolyte – rebalancing the states of charge of both electrolytes without introducing extra ions. We demonstrate the repeated capacity recovery with DHAQ | potassium ferro-/ferricyanide flow battery in basic conditions, and show the approach is also effective for anthraquinone-2,7-disulfonate in acid. Electrochemical regeneration strategies may extend the useful lifetime of many water-soluble organic molecules with anthraquinone core structures in electrochemical cells.

25 ENERGY STORAGE↗
DOE OSTI2023

Effects of film thickness on electrochemical properties of nanoscale polyethylenedioxythiophene (PEDOT) thin films grown by oxidative molecular layer deposition (oMLD)

Poly(3,4-ethylene dioxythiophene) (PEDOT) has a high theoretical charge storage capacity, making it of interest for electrochemical applications including energy storage and water desalination. Nanoscale thin films of PEDOT are particularly attractive for these applications to enable faster charging. Recent work has demonstrated that nanoscale thin films of PEDOT can be formed using sequential gas-phase exposures via oxidative molecular layer deposition, or oMLD, which provides advantages in conformality and uniformity on high aspect ratio substrates over other deposition techniques. But to date, the electrochemical properties of these oMLD PEDOT thin films have not been well-characterized. In this work, we examine the electrochemical properties of 5–100 nm thick PEDOT films formed using 20–175 oMLD deposition cycles. We find that film thickness of oMLD PEDOT films affects the orientation of ordered domains leading to a substantial change in charge storage capacity. Interestingly, we observe a minimum in charge storage capacity for an oMLD PEDOT film thickness of ~30 nm (60 oMLD cycles at 150 °C), coinciding with the highest degree of face-on oriented PEDOT domains as measured using grazing incidence wide angle X-ray scattering (GIWAXS). Thinner and thicker oMLD PEDOT films exhibit higher fractions of oblique (off-angle) orientations and corresponding increases in charge capacity of up to 120 mA h g -1 . Electrochemical measurements suggest that higher charge capacity in films with mixed domain orientation arise from the facile transport of ions from the liquid electrolyte into the PEDOT layer. Greater exposure of the electrolyte to PEDOT domain edges is posited to facilitate faster ion transport in these mixed domain films. In conclusion, these insights will inform future design of PEDOT coated high-aspect ratio structures for electrochemical energy storage and water treatment.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2023

Electrochemical Imaging of Interfaces in Energy Storage via Scanning Probe Methods: Techniques, Applications, and Prospects

Developing a deeper understanding of dynamic chemical, electronic, and morphological changes at interfaces is key to solving practical issues in electrochemical energy storage systems (EESSs). To unravel this complexity, an assortment of tools with distinct capabilities and spatiotemporal resolutions have been used to creatively visualize interfacial processes as they occur. This review highlights how electrochemical scanning probe techniques (ESPTs) such as electrochemical atomic force microscopy, scanning electrochemical microscopy, scanning ion conductance microscopy, and scanning electrochemical cell microscopy are uniquely positioned to address these challenges in EESSs. We describe the operating principles of ESPTs, focusing on the inspection of interfacial structure and chemical processes involved in Li-ion batteries and beyond. We discuss current examples, performance limitations, and complementary ESPTs. Finally, we discuss prospects for imaging improvements and deep learning for automation. We foresee that ESPTs will play an enabling role in advancing EESSs as we transition to renewable energies.

25 ENERGY STORAGE↗
DOE OSTI2021

Investigating Effects of Operational Parameters on the Rate of Electrochemical Cleaning of Chromium Deposits on Strontium-Doped Lanthanum Manganite Cathodes in Solid Oxide Fuel Cells

Chromium poisoning of the cathode remains a significant obstacle to the stable long-term performance of solid oxide fuel cells. This study reports, a quick, in-situ mitigation method, called electrochemical cleaning. By applying a mild anodic bias, the electrochemical deposition reactions of chromium-containing species are reversed. Chromium vapor species are formed, freeing active electrochemical sites in the air electrode. An LSM/YSZ-based cell was exposed to Cr vapors at 800ºC and then subjected to electrochemical cleaning. Cell performance recovery was evidenced by current-voltage and EIS measurements. Chromium removal was verified using SEM and EDS analyses. The cyclability of the electrochemical cleaning was tested by repeated poisoning and cleaning of another cell. Investigation into the effect of cell operating parameters (current density and cell temperature) on the rate of cleaning is discussed.

30 DIRECT ENERGY CONVERSION↗
DOE OSTI2020

An Efficient Electrochemical Tanks-in-Series Model for Lithium Sulfur Batteries

This article applies and efficiently implements the Tanks-in-Series methodology ( J. Electrochem. Soc. , 167 , 013534 (2020)) to generate a computationally efficient electrochemical model for Lithium-Sulfur batteries. The original Tank model approach for Lithium-ion batteries is modified to account for porosity changes with time. In addition, an exponential scaling method is introduced that enables efficient simulation of the model equations to address the wide range of time constants present for different reactions in the Lithium-Sulfur system. The Tank Model achieves acceptable voltage error even for transport-limited discharged conditions. Predictions of internal electrochemical variables are examined, and electrochemical implications of the approximations discussed. This suggests significant potential for real-time applications such as optimal charging, cell-balancing, and estimation, and represents a step forward in efforts to incorporate detailed electrochemical models in advanced Battery Management Systems for Lithium-Sulfur batteries.

Parke, Caitlin D. (ORCID:0000000177324044)↗
DOE OSTI2022

Perspective—Electrochemistry in Understanding and Designing Electrochemical Energy Storage Systems

The number of publications in electrochemical energy storage has increased exponentially in the past decades, focusing mostly on materials science. The electrochemical process controlling the observed overall performances is often not well discussed. This article highlights the importance of understanding rate-limiting steps in the electrochemical process which change dynamically at different conditions and scales. Applying electrochemistry to identify and overcome those rate-limiting steps in the electrochemical devices is the prerequisite to discovering effective solutions and designing different batteries to further advance electrochemical energy storage systems for a broad range of various applications.

25 ENERGY STORAGE↗
DOE OSTI2022

Spatiotemporal Visualization and Chemical Identification of the Metal Diffusion Layer at the Electrochemical Interface

The diffusion layer created by transition metal dissolution is ubiquitous at the electrochemical solid-liquid interface and plays a key role in determining electrochemical performance. Tracking the spatiotemporal dynamics of the diffusion layer has remained an unresolved challenge. With spatially resolved synchrotron X-ray fluorescence microscopy and micro-X-ray absorption spectroscopy, we demonstrate the in situ visualization and chemical identification of the dynamic diffusion layer near the electrode surface under electrochemical operating conditions. Finally, our method allows for direct mapping of the reactive electrochemical interface and provides insights into engineering the diffusion layer for improving electrochemical performance.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2024

In Situ Liquid Electron Microscope Cells Strongly Attenuate Electrochemical Behavior

In situ electrochemical Scanning Transmission Electron Microscopy (ec-S/TEM) probes the dynamics of electrochemical processes in real time and at high spatial resolution. This method utilizes microfabricated electrochemical cells, with enclosed dimensions of 800 μm wide, 800 μm long, and 1–2 μm tall, with electron-transparent silicon nitride windows. Working, counter, and reference electrodes in the configuration studied are deposited Pt with a planar surface area of about 1 μm 2 and a height of 50 nm. The cell confines the electrolyte within a 1 μm tall channel, and the microfabricated electrodes have a non-standard geometry, are coplanar, and are not front-facing. As such, standard assumptions of electrochemical experiments do not apply. COMSOL modeling was used to compare and contrast differences in electrochemical behavior between conventional experimental setups and the in situ ec-S/TEM cells. Cell height strongly affected voltammogram measurements: peak magnitudes and shifts correlate directly to cell height. Reactant concentration above the electrode quickly decreases during deposition, leading to a planar diffusion-dominated regime. The concentration gradient prioritizes particle growth along the thin edges of the electrode and not on the planar part of the electrode. Experiments done in the ec-S/TEM ex situ of a TEM verify the model’s accuracy.

Wittman, Reed M. [Oak Ridge National Laboratory (O↗
DOE OSTI2020

Integrating Data Sources for Improved Safeguards and Accountancy of Electrochemical Fuel Reprocessing Systems. Final Report

Electrochemical reprocessing (also commonly known as “pyroprocessing”) of used nuclear fuel is an alternative to aqueous reprocessing that confers a number of advantages, including the ability to process more recently-discharged fuel, smaller resultant waste volumes, and the lack of isolation of plutonium in the product stream. While electrochemical reprocessing systems have seen a significant research and development effort, nuclear safeguards and security of these systems remains under-developed, particularly given the significant differences in operating environment and process flowsheet compared with established aqueous methods. Objective 4 of DOE’s nuclear energy research and development activities in Nuclear Energy Research and Development Roadmap is: “Understand and minimize the risks of nuclear proliferation and terrorism.” Material Control & Accountancy (MC&A) programs at nuclear processing plants deter and detect theft and diversion of nuclear material by both outside and inside adversaries. Empirical modeling and data analytics of online measurements and state indicators can improve the timeliness of detection and reduce the uncertainty in accountancy measures. To support the development and demonstration of such methods, data are needed that capture expected measurement values collected throughout electrochemical reprocessing facilities. A review of the available literature of current research in measurements for electrochemical reprocessing systems identified twenty-two candidate measurement methodologies, which characterize fuel/salt composition, concentrations of various isotopes and elements, and operational parameters throughout the reprocessing facility. Four primary measurement methodologies have been simulated based on either physical simulations or empirical correlations: gamma emissions, neutron emissions, hybrid k-edge densitometry (HKED), and cyclic voltammetry. Initial investigation into the use of these measures for process monitoring and detection suggests the approach is viable and worthy of further investigation. This report summarizes efforts to generate signatures of key measurements during operation of electrochemical reprocessing facilities and initial investigation of data analytics to support process monitoring, diversion detection, and accountancy.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2024

N-Doped Graphene (N-G)/MOF(ZIF-8)-Based/Derived Materials for Electrochemical Energy Applications: Synthesis, Characteristics, and Functionality

In recent years, graphene-type materials originating from metal–organic frameworks (MOFs) or integrated with MOFs have exhibited notable performances across various applications. However, a comprehensive understanding of these complex materials and their functionalities remains obscure. While some studies have reviewed graphene/MOF composites from different perspectives, due to their structural–functional intricacies, it is crucial to conduct more in-depth reviews focusing on specific sets of graphene/MOF composites designed for particular applications. In this review, we thoroughly investigate the syntheses, characteristics, and performances of N-G/MOF(ZIF-8)-based/derived materials employed in electrochemical energy conversion and storage systems. Special attention is given to realizing their fundamental functionalities. The discussions are divided into three segments based on the application of N-G/ZIF-8-based/derived materials as electrode materials for batteries, electrodes for electrochemical capacitors, and electrocatalysts. As electrodes for batteries, N-G/MOF(ZIF-8) materials can mitigate issues like an electrode volume expansion for Li-ion batteries and the ‘shuttle effect’ for Li-S batteries. As electrodes for electrochemical capacitors, these materials can considerably improve the ion transfer rate and electronic conductivity, thereby enhancing the specific capacitance while maintaining the structural stability. Also, it was observed that these materials could occasionally outperform standard platinum-based catalysts for the electrochemical oxygen reduction reaction (ORR). The reported electrochemical performances and structural parameters of these materials were carefully tabulated in uniform units and scales. Through a critical analysis of the present synthesis trends, characteristics, and functionalities of these materials, specific aspects were identified that required further exploration to fully utilize their inherent capabilities.

Electrochemistry↗