Oxidation Potential Research Articles

Exploring potential of graphene oxide as an alternative antiviral approach for influenza A H1N1.

Aim: Graphene oxide (GO), known for its distinctive physicochemical properties, shows promise as a nanomaterial capable of combating infectious agents. This study investigates the efficacy of GO nanoparticles in restricting influenza A H1N1 replication in MDCK cells.Methods: GO nanoparticles were synthesized. After evaluating the toxicity of GO nanoparticles, the antiviral activity of the highest nontoxic concentration of GO against influenza A H1N1 in MDCK cells was studied.Results: GO treatments resulted in substantial decreases in virus titers, as shown via hemagglutination assay, TCID50 assay and real-time PCR analysis.Conclusion: This study emphasizes that GO nanoparticles have a high level of effectiveness against influenza A H1N1 viruses, making them an intriguing option for various antiviral uses.

Tracking Water Dissociation on RuO2(110) Using Atomic Force Microscopy and First-Principles Simulations.

The interaction between interfacial water and transition metal oxides is a primary enabling step for the oxygen evolution reaction (OER). RuO2 is a prototypical OER electrocatalyst whose ability to activate interfacial water molecules is essential to its OER activity. We image the dissociation of surface water into OH* and O* on RuO2(110), where * denotes adsorbed species, using atomic force microscopy. Starting from the surface-bound water molecules, which form a one-dimensional network along the rows of Ru surface sites, increasing the oxidative potential strips hydrogen away and transforms the water molecules into OH* and O*. This oxidative step changes the pattern of the adsorbates from one- to two-dimensional. First-principles calculations with interfacial polarization, capacitive charging, and adsorbate interactions attribute this evolution to the cooperative dehydrogenation of adsorbed water and OH* on RuO2. We use these results to map the surface phase diagram of RuO2(110) and provide a quantitative interpretation of its cyclic voltammetry. Our result provides the visualization of the water dissociation on a conductive oxide surface, a critical step in the OER, and demonstrates that the water activation is a collective phenomenon at RuO2(110) electrodes.

Seasonal dynamics of bacterial community structure and function in the surf zone seawater of a recreational beach in Ostend, Belgium.

Despite the importance of bacteria in surf zone water quality, detailed insights into their community composition, functions, and seasonal dynamics at recreational beaches are scarce. This study conducted year-long, weekly monitoring of bacterial communities and environmental factors at a recreational beach in Ostend, Belgium. Using full-length 16S rRNA gene sequencing, we correlated bacterial composition and predicted functions with environmental factors to identify potential drivers. Bacterial communities were significantly affected by seasonal variations in chlorophyll a (Chl a), net primary productivity (NPP), and seawater temperature (SWT), with minimal influence from faecal inputs due to human activities. Spring showed distinct abundances of Planktomarina, Amylibacter, and Sulfitobacter, positively correlated with Chl a and related to sulphur oxidation potential. Summer had higher abundances of Cryomorphaceae, likely enhancing chemoheterotrophy. Beginning in mid to late fall and extending into winter, bacterial communities underwent substantial changes. Fall featured a distinctive enrichment of Thioglobaceae, inversely correlated with Chl a. Winter was dominated by Methylophilaceae (OM43 clade), negatively correlated with Chl a, NPP, and SWT. Both seasons exhibited elevated levels of potentially pathogenic phenotypes and predicted functions related to methanol oxidation and methylotrophy. This study provides a baseline for understanding how surf zone bacterial communities respond to environmental changes and impact health.

Enabling Efficient Oxygen Evolution via Anchoring Carbon-Layer-Confined RuOx on a Well-Matched Substrate.

Oxygen evolution reaction (OER) is a multistep proton-coupled four-electron process with sluggish kinetics, which seriously limits the hydrogen production efficiency, thus it is of great importance to develop an efficient and stable OER catalyst. In this study, a two-step differential pyrolysis strategy is employed to design a three-dimensional porous microstructured material consisting of RuOx nanoparticles coated by a thin-layer carbon, where the active particles were isolated in separate chambers and the RuOx nanoparticles mainly existed in the form of a heterogeneous interface between RuO2 and partial metallic Ru. The preparation parameters of the catalysts are optimized via combining transient and steady-state polarization properties, and the target catalyst Cat-500-1.5t shows the best OER catalytic performance after ca. 60 h of a chronopotentiometry test in an acidic medium with a much smaller performance change than other samples. The unique design of adopting a carbon layer to form separate reaction chambers largely mitigates the excessive oxidation loss of the active components under strong oxidation potential. The suitability of the catalyst with the loaded substrate and test media is explored, and in an acidic medium, the carbon paper is much better than the titanium fiber, while in an alkaline medium, the titanium fiber is obviously superior to the carbon paper. On both carbon paper and titanium fiber, the performance in an alkaline medium outperforms that in an acidic medium, and the possible reasons for the performance difference are analyzed. Herein, to obtain the actual electrocatalytic performance, the optimal design of the catalyst structure and matching suitable conductive substrate in a specific medium are quite necessary, which provides a feasible strategy for the acquisition of efficient and stable electrocatalysts and the desirable presentation of performance.

Vertically Expanded Covalent Organic Frameworks for Photocatalytic Water Oxidation into Oxygen

Covalent organic frameworks with unique π architectures and pores could be developed as photocatalysts for transformations. However, they usually form π‐stacking layers, so that only surface layers function in photocatalysis. Here we report a strategy for developing vertically expanded frameworks to expose originally inaccessible active sites hidden in layers to catalysis. We designed covalently linked two‐dimensional cobalt(II) porphyrin layers and explored coordination bonds to connect the cobalt(II) porphyrin layers with bidentate ligands via a three‐component one‐pot polymerization. The frameworks expand the interlayer space greatly, where both the up and down faces of each cobalt(II) porphyrin layer are exposed to reactants. Unexpectedly, the vertically expanded frameworks increase skeleton oxidation potentials, decrease exciton dissociation energy, improve pore hydrophilicity and affinity to water, and facilitate water delivery. Remarkably, these positive effects work collectively in the photocatalysis of water oxidation into oxygen, with an oxygen production rate of 1155 µmol g−1 h−1, a quantum efficiency of 1.24% at 450 nm, and a turnover frequency of 1.39 h−1, which is even 5.1‐fold as high as that of the π‐stacked frameworks and ranks them the most effective photocatalysts. This strategy offers a new platform for designing layer frameworks to build various catalytic systems for chemical transformations.

Vertically Expanded Covalent Organic Frameworks for Photocatalytic Water Oxidation into Oxygen.

Covalent organic frameworks with unique π architectures and pores could be developed as photocatalysts for transformations. However, they usually form π-stacking layers, so that only surface layers function in photocatalysis. Here we report a strategy for developing vertically expanded frameworks to expose originally inaccessible active sites hidden in layers to catalysis. We designed covalently linked two-dimensional cobalt(II) porphyrin layers and explored coordination bonds to connect the cobalt(II) porphyrin layers with bidentate ligands via a three-component one-pot polymerization. The frameworks expand the interlayer space greatly, where both the up and down faces of each cobalt(II) porphyrin layer are exposed to reactants. Unexpectedly, the vertically expanded frameworks increase skeleton oxidation potentials, decrease exciton dissociation energy, improve pore hydrophilicity and affinity to water, and facilitate water delivery. Remarkably, these positive effects work collectively in the photocatalysis of water oxidation into oxygen, with an oxygen production rate of 1155 µmol g-1 h-1, a quantum efficiency of 1.24% at 450 nm, and a turnover frequency of 1.39 h-1, which is even 5.1-fold as high as that of the π-stacked frameworks and ranks them the most effective photocatalysts. This strategy offers a new platform for designing layer frameworks to build various catalytic systems for chemical transformations.

Peracetic acid treatment for removing steroid hormones in a pilot-scale wastewater installation

The global water scarcity challenge urges sustainable solutions such as wastewater reuse, which is crucial to alleviate pressure on dwindling freshwater sources. However, this approach must address the presence of emerging pollutants (EPs), demanding specific treatment processes to ensure water safety and environmental protection. Peracetic acid (PAA) has garnered global interest due to its high oxidation potential and production of low-toxicity byproducts, making it a promising alternative for wastewater decontamination. This study aimed to assess PAA efficacy in removing three EPs: estrone (E1), 17β-estradiol (E2), and 17α-ethinylestradiol (EE2). Conducted in a pilot-scale wastewater treatment facility using real wastewater, the study explored six operational conditions, with varying PAA concentrations (5 mg/L to 15 mg/L) and hydraulic retention times (HRT) of 5, 10, and 15 min. Control parameters were monitored throughout the study. The condition with 15 mg/L PAA and 15 min HRT was the most efficient achieving over 85 % removal efficiency for all three compounds. The condition with 15 mg/L PAA and 10 min HRT was less efficient, achieving 70 % removal for E1 and 60 % and 44 % for E2 and EE2, respectively. A Spearman correlation matrix identified temperature and E. coli as strongly correlated with EPs removal, potentially influencing PAA decay. Overall, PAA demonstrated effective removal of target EPs under real wastewater conditions, underscoring its viability as a sustainable alternative for enhancing wastewater treatment processes, contributing to environmental protection and public health. Future studies could explore the long-term efficiency of PAA application and its scalability.

The indirect global warming potential of methane oxidation in the IPCC’s sixth assessment report

Abstract Greenhouse-gas emission (GHG) metric values for methane in the sixth assessment report by the Intergovernmental Panel on Climate Change (IPCC) include the indirect effect associated to the oxidation of methane to CO2. An analysis of the figures provided by the IPCC reveals they assume that in average 75% of methane is ultimately oxidized to CO2, while the remaining 25% is converted to intermediate degradation products, most notably formaldehyde, which are removed from the atmosphere via wet and dry deposition and treated by the IPCC as a potential carbon sink in terrestrial and aquatic ecosystems. In this short article we present a critique to this assumption, based on existing knowledge about the environmental fate of methane’s degradation products. We conclude that any assumption other than full degradation of methane to CO2 in a rather short time frame is questionable, whereby the default CO2 yield from this oxidation, as far as GHG metrics are concerned, should be 100%. We re-calculate values for the global warming potential (GWP) metric in accordance with our findings, resulting in an increase in GWP100 from 29.8 and 27.0 to 30.40 and 27.65 kg CO2-equivalents/kg fossil and biogenic methane, respectively. Although we only present the implications in terms GWP, our proposal is conceptually valid for other GHG metrics as well.

Visible light activation of permanganate by nitrogen vacancy-modified g-C3N4: Insight into the role of photo-generated electrons and holes

The photo-activation of permanganate (PM) for pollutant degradation in water has garnered significant interest due to its potential, yet it is impeded by efficiency constraints. In this study, the nitrogen-vacancy (NV) engineered graphitic carbon nitride (CN) catalysts with high light absorption, well photocarrier separation, and robust photoreduction capability were employed to activate PM under visible light irradiation (Vis) for sulfadiazine degradation. A high first-order rate constant of 0.185 min−1 was observed with the Vis/PM/NV-modified CN system, which was 25.2 and 7.1 times greater than those from Vis/PM and Vis/PM/CN system respectively. More interestingly, it was found that PM predominantly engaged with photo-generated holes as Lewis acid sites, elevating its oxidation potential and concurrently stimulating the production of photo-generated electrons. Meanwhile, dissolved oxygen (DO) was reduced by photo-generated electrons to form superoxide ions, singlet oxygen, and hydroxyl radicals. These produced reactive species through the synergistic activation of PM and DO, finally participated in the degradation of pollutants. Furthermore, the versatility and reusability of NV-CN catalysts were assessed under different reaction conditions, demonstrating promising prospects for practical applications. The results will contribute to a comprehensive understanding of the mechanism of photoactivation of PM for pollutant degradation.

Deep oxidation of NO via catalytic ozonation

ABSTRACT In addition to selective catalytic reduction (SCR) and selective non-catalytic reduction (SNCR) which are available to remove NOx from flue gas, oxidation method is receiving more and more attention because this method makes it possible to remove NOx and SO2 from flue gas simultaneously by wet scrubbing. O3 as a strong oxidant has a high oxidation capacity and it can oxide NO to N2O5 which has a higher water solubility compared with NO2. However, it needs a long reaction time and the escape of unreacted ozone may cause secondary pollution. In this study, FeMnCo/Al2O3 catalyst and FeMnCe/Al2O3 catalyst were prepared and applied to enhance the deep oxidation of NOx with ozone and reduce O3 slip. Effects of various operating parameters such as O3/NO ratio, gas residence time, and operating temperature were evaluated, and the results demonstrate that N2O5 began to generate when O3/NO ratio was higher than 1.0 and increased with increasing O3/NO ratio. Little residual O3 was formed in the presence of catalyst, while 350 ppm O3 was measured at the outlet gas when O3/NO ratio was controlled at 2.0. The N2O5 conversion efficiency increased with increasing gas residence time and operating temperature, and the highest N2O5 conversion efficiency was achieved at 100°C. Furthermore, the conversion efficiency remained around 90% during 20 h operation over FeMnCe/Al2O3 catalyst with an O3/NO ratio of 1.73, a gas residence time of 1.2 s, and a temperature of 100°C. On the other hand, the N2O5 conversion efficiency remained around 80% during 3 h operation over FeMnCo/Al2O3 catalyst. Overall, FeMnCe/Al2O3 catalyst reveals good potential for deep oxidation of NO by O3 and can be further developed as a viable catalyst for reducing NO emission from industries. Implications: In this study, FeMnCo/Al2O3 catalyst and FeMnCe/Al2O3 catalyst were applied to enhance the deep oxidation of NO into N2O5 with O3. The catalysts can improve the conversion of NO into N2O5, shorten the reaction time and reduce the unreacted O3 slip, which are beneficial to reduce the size of the reactor required and cost of APCDs (air pollution control devices) in practical application. This method can make it possible to simultaneously remove NOx and SO2 from flue gas by wet scrubbing for reducing NO emissions from industries, especially small and medium scaled industries, to meet increasingly stringent emission standards.

Impact of PM2.5 filter extraction solvent on oxidative potential and chemical analysis

ABSTRACT Fine particulate matter (PM2.5) is hypothesized to induce oxidative stress, and has been linked to acute and chronic adverse health effects. To better understand the risks and underlying mechanisms following exposure, PM2.5 is collected onto filters but prior to toxicological analysis, particles must be removed from filters. There is no standard method for filter extraction, which creates the possibility that the methods of extraction selected can alter the chemical composition and ultimately the biological implications. In this study, comparisons were made between extraction solvents (methanol (MeOH), dichloromethane (DCM), 0.9% saline, and Milli-Q water) and the results of oxidative potential and elemental concentration analysis of PM2.5 collected across sites in Arkansas, USA. Significant differences were observed between solvents, with DCM having significantly different results compared to all other extraction solvents (p ≤ 0.001). Significant correlations between element, black carbon, and PM2.5 concentrations and oxidative potential were observed. The observed correlations were extraction solvent dependent. For example, in saline extracted samples, oxidative potential had significant negative correlations with: Ba, Cd, Ce, Co, Ga, Mn and significant positive correlations with: Cr, Ni, Th, U. While in MeOH extracted samples, significant positive correlations were only between oxidative potential and Ga, U and significant negative correlations with V. This indicates that PM2.5 samples extracted with different solvents will yield different conclusions about the causal components. This study highlights the importance of filter extraction methods in interpretation of oxidative potential results and comparisons between studies. Implications: While there is no standard method for PM2.5 filter extraction, variation of extraction methods impact analytical results. This project identifies that extraction method variation, particularly extraction solvent selection, leads to discrepancies in chemical and toxicological analysis for PM2.5 collected on the same filter. This work highlights the need for methods standardization to support accurate comparisons between PM2.5 research studies, thus providing better understanding of PM2.5 across the globe.

Harnessing Oxidizing Potential of Nickel for Sustainable Hydrocarbon Functionalization.

While the oxidative chemistry of transition metals such as iron and copper is a highly developed area of investigation, the study of similar chemistry with nickel is much younger. However, nickel offers rich coordination chemistry with oxygen and other oxidants and is a promising avenue of research for applications such as sustainable hydrocarbon functionalization. Herein, we summarize the progress made recently in nickel coordination chemistry relevant to hydrocarbon functionalization and offer our perspectives on open questions in the field.

Temporal Variations in Health Risk Indices and Combustion-Derived Components of PM1.0: Focus on Terephthalate and Levoglucosan

This study evaluated the health risks and chemical composition of PM1.0 and PM2.5 in Incheon, South Korea, emphasizing the critical role of particle size in public health impacts. The average concentrations were 10.89 μg/m³ for PM2.5 and 8.11 μg/m³ for PM1.0. PM1.0 displayed higher proportions of carbonaceous components and water-soluble ions, predominantly formed through photochemical reactions and atmospheric chemistry processes. Health risk assessments, using the Benzo[a]pyrene toxic equivalency factor, mutagenic and carcinogenic potential, risk index, and oxidative potential (DTT-OP), indicated that PM1.0 poses significantly higher health risks per unit mass compared to PM2.5. Key components in PM1.0, such as levoglucosan and terephthalic acid (TPA), indicate significant contributions from combustion sources like biomass burning and plastic incineration, particularly at night. PM1.0 showed higher carcinogenic and mutagenic risks than PM2.5. The correlation between levoglucosan, PAHs, and TPA supports common combustion origins. Effective management of combustion-related emissions is crucial for reducing health risks associated with PM1.0. The overall average risk index for PM1.0 is 1.30 times higher than PM2.5, implying that, on average, PM1.0 poses a 30% higher health risk across the measured indices compared to PM2.5. This study emphasizes the need for targeted management of combustion emissions, particularly those from plastic and fuel combustion, to mitigate the health risks posed by PM1.0. Effective control of the precursors contributing to PM1.0 formation is crucial for reducing the adverse health impacts of air pollution.

Photoinduced Electrochemiluminescence Immunoassays.

Optimization of electrochemiluminescence (ECL) immunoassays is highly beneficial for enhancing clinical diagnostics. A major challenge is the improvement of the operation conditions required for the bead-based immunoassays using the typical [Ru(bpy)3]2+/tri-n-propylamine (TPrA) system. In this study, we report a heterogeneous immunoassay based on near-infrared photoinduced ECL, which facilitates the imaging and quantitative analysis of [Ru(bpy)3]2+-modified immunobeads at low anodic potential. The photovoltage generated by the photoanode under near-infrared light promotes oxidation processes at the electrode/electrolyte interface, thus considerably lowering the onset potential for both TPrA oxidation and ECL emission. The anti-Stokes shift between the excitation light (invisible to the human eyes) and the visible emitted light results in a clear and stable signal from the immunobeads. In addition, it offers the possibility of site-selective photoexcitation of the ECL process. This approach not only meets the performance of traditional ECL immunoassays in accuracy but also offers the additional benefits of lower potential requirements and enhanced stability, providing a new perspective for the optimization of commercial immunoassays.

In silico Evaluation of NO-Sartans against SARS-CoV-2.

Numerous clinical trials are currently investigating the potential of nitric oxide (NO) as an antiviral agent against coronaviruses, including SARS-CoV-2. Additionally, some researchers have reported positive effects of certain Sartans against SARS-CoV-2. Considering the impact of NO-Sartans on the cardiovascular system, we have compiled information on the general structure, synthesis methods, and biological studies of synthesized NOSartans. In silico evaluation of all NO-Sartans and approved sartans against three key SARS-CoV- -2 targets, namely Mpro (PDB ID: 6LU7), NSP16 (PDB ID: 6WKQ), and ACE-2 (PDB ID: 1R4L), was performed using MOE. Almost all NO-Sartans and approved sartans demonstrated promising results in inhibiting these SARS-CoV-2 targets. Compound 36 (CLC-1280) showed the best docking scores against the three evaluated targets and was further evaluated using molecular dynamics (MD) simulations. Based on our in silico studies, CLC-1280 (a Valsartan dinitrate) has the potential to be considered as an inhibitor of the SARS-CoV-2 virus. However, further in vitro and in vivo evaluations are necessary for the drug development process.

Far-Ultraviolet C Disinfection Reduces Oxidative Damage to the Cornea Compared to Povidone-Iodine Disinfection

Far-ultraviolet C (far-UVC) light shows promise for pathogen control but its safety and efficacy for corneal disinfection remain unclear. In this study, safe far-UVC dosages were investigated for corneal disinfection and its germicidal performance and oxidative damage potential to 5% povidone-iodine (PVP-I) were compared. Rat corneas were exposed to varying 222 nm far-UVC doses (3–60 mJ/cm2) and assessed for ocular damage, apoptosis, and oxidative stress to determine the safe dose of far-UVC. Far-UVC at 30 mJ/cm2 induced corneal apoptosis and oxidative damage, but 15 mJ/cm2 caused no apoptosis or oxidative damage. At this optimized dose (9 mJ/cm2), far-UVC achieved 90.5% sterilization, exceeding 5% PVP-I (80.8%), with significantly less oxidative damage and cell death in the cornea. In conclusion, our study demonstrates that the use of 5% povidone-iodine (PVP-I) for disinfection results in significant oxidative damage to the corneal tissue. However, a safe dosage of far-UVC light exhibited a promising disinfection effect without causing oxidative damage to the corneal tissue. Far-UVC offers a promising alternative for corneal disinfection but requires careful dosage control (≤30 mJ/cm2) to avoid ocular surface harm.

High-efficiency treatment of oily wastewater by photocatalytic in-situ Fenton oxidation under visible light

Oily wastewater poses a significant threat to environmental safety, and complex water environments have caused numerous disturbances in oil pollution treatment. Therefore, constructing composite systems is expected to improve oil pollution treatment efficiency. This study developed an efficient photocatalytic in-situ Fenton oxidation system, HTCC@ZnFe2O4/Ag3PO4 (HZFA), loaded onto polypropylene spheres (PP) for treating oily wastewater (diesel oil) in complex environments. The built-in electric field of HZFA promotes photogenerated carrier separation, enhancing photocatalytic effect. At a diesel concentration of 3.2 g/L, performance of HZFA degraded diesel in deionized water and artificial seawater (ASW) were 60.80 % and 52.62 %, respectively, much higher than a pure photocatalytic system (13.84 %). The dual system compensated for single system defects like instability and narrow application range, achieving 8 effective cycles in ASW. Experimental and computational results showed that high oxidation and reduction potentials in the dual system promoted hydrocarbon oxidative degradation and H2O2 production/activation. The amount of OH, O2−, and h+ produced in different environments is fundamental for the stabilization of catalytic degradation by HZFA. GC–MS and DFT analysis revealed potential oxidative chain-breaking processes for diesel components like alkanes, aromatics, alcohols, acids, aldehydes, and esters. This study offers a new method for green and efficient oily wastewater treatment, overcoming inherent defects of traditional Fenton, with broad application prospects.

Shape-dependent CO chemisorption on Pt13 nanocluster deposited on reduced TiO2(110)

This article delves into the impact of nanoparticle shape on CO chemisorption and the reactivity of Pt13 nanocatalysts supported on reduced TiO2(110). Distinct reactivity in carbon monoxide adsorption is observed among nanoparticles, all composed of 13 platinum atoms but varying in shape. The calculated formation and CO adsorption energies are correlated to the electronic properties of the system and the oxidation states of the Pt atoms involved. Through an analysis of band shifting during the deposition of Pt clusters onto the oxide, and a comparison of the valence band maximum with the measured oxidation potential for the CO to CO2 reaction, we make predictions about the system's oxidation capability in this reaction. Our findings suggest that Pt13 clusters with cuboid, double triangle DT2 and octahedral Oh shapes, supported on the surface, are particularly advantageous for catalyzing the conversion of CO to CO2. Within these geometries, several configurations for CO adsorption are evaluated, focusing on the ratio between anionic and cationic Pt sites. This ratio appears to govern the activity for CO oxidation, aligning with recent experimental reports.

Fluence-Dependent Photoinduced Charge Transfer Dynamics in Polymer-Wrapped Semiconducting Single-Walled Carbon Nanotubes.

Because an individual single-walled carbon nanotube (SWNT) can absorb multiple photons, the exciton density within a single tube depends upon excitation conditions. In SWNT-based energy conversion systems, interactions between excitons and charges make it possible for multiple types of charge transfer reactions. We exploit a SWNT-molecular donor-acceptor hybrid system (R-PBN(b)-Ph6-PDI-[(6,5) SWNT]) that fixes spatial organization and stoichiometry of perylene diimide (PDI) electron acceptors on the nanotube surface, to elucidate how excitation fluence affects ultrafast charge separation (CS) and the nature of charge recombination (CR) dynamics triggered upon SWNT near-infrared excitation. Pump-probe data characterizing these photoinduced CS and thermal CR reactions were acquired over excitation fluences that produce ∼5-125 excitons per 700 nm long nanotube. These experiments show that optical excitation gives rise to CS states in which PDI radical anions (PDI-•) and SWNT hole polarons (SWNT•+) have geminate and nongeminate spatial relationships. Under low excitation fluences, the observed dynamics reflect CR reactions of these geminate and nongeminate CS states. As excitation fluence increases, persistent excitons, which have not undergone CS, undergo reaction with ([SWNT(•+)n]-(PDI-•)n) CS states to produce lower-energy CS states that are characterized by hole (SWNT•+) and electron (SWNT•-) polarons. When nongeminate SWNT•+ and SWNT•- charge carriers are generated, CR dynamics depend on the time scale required for these oppositely charged solvated SWNT polarons to encounter each other. Because SWNT excitons have substantial excited-state reduction (1E-/*) and excited-state oxidation (1E*/+) potentials, they can drive additional charge transfer reactions involving initially prepared CS states under experimental conditions where excess excitons are present.

Machine learning predictions of onset and oxidation potentials for methanol and ethanol electrooxidation: Comprehensive analysis and experimental validation

The onset and oxidation potentials of electrochemical reactions are pivotal in assessing catalytic energy efficiency, spanning applications across various domains, including sustainable energy generation. However, predicting these potentials presents a complex and uncharted challenge. In this study, we present a pioneering approach to developing predictive models for the onset and oxidation potentials within electrochemical reactions linked to the oxidation of methanol and ethanol. We have devised a comprehensive pipeline from Data Collection, Information Extraction, and Preprocessing and assessed the performance of different regression models: Linear, Random Forest, and XGBoost. For the oxidation potential prediction, an RMSE of 0.169 and an R2 value of 0.814 were achieved. Similarly, for the onset potential prediction, the model yielded an RMSE of 0.185 and an R2 value of 0.839. The models were further evaluated using feature importance and SHAP values, enhancing our understanding of their predictive mechanisms and providing more comprehension of the features. Additionally, we conducted experimental validations by comparing the predicted outcomes to actual results obtained from methanol and ethanol oxidation experiments carried out in a chemical laboratory. This validation process included the utilization of platinum, gold, nickel foam, steel and RuO2/FTO electrodes. Encouragingly, the experimental validation yielded promising findings, exhibiting an RMSE of 0.0967 for the onset potential and an RMSE of 0.0234 for the oxidation potential.