Christopher D. Easton

Nonthermal plasma (NTP) offers a promising electrified route for CO2 methanation by enabling molecular activation under mild conditions; however, the role of catalyst supports in governing plasma–catalyst interactions and reaction pathways remains insufficiently understood. In this work, we systematically investigate Ni catalysts supported on Al2O3, ZrO2, BaTiO3, commercial CeO2, and high surfacearea CeO2 (HC300) to elucidate how support properties influence plasmaassisted CO2 methanation. Plasma catalytic testing revealed that while support materials alone have limited impact on overall CO2 conversion, the incorporation of Ni significantly enhances activity and CH4 selectivity, with performance strongly correlated to activemetal dispersion and surface basicity. Ni/HC300 exhibited the highest dispersion (58%), strongest weakbasicity population, and superior performance (82% CO2 conversion, 100% CH4 selectivity). Insitu comparative diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) provided mechanistic insights, showing that surface reactions dominate the conversion under NTP conditions, and both formate and CO pathways occur over the catalysts under investigation. The dominant ratedetermining steps involve hydrogenation of formate (HCOO*) or formyl (HCO*) species, or methoxy (CH3O*) dissociation depending on the nature of the support. Overall, this work establishes clear structure–property–function relationships, offering mechanistic guidance for rational catalyst design in plasmaassisted CO2 hydrogenation.

A In ₂ O ₃ /ZrO ₂ catalyst was deposited onto highly conductive 3D-printed stainless steel scaffolds, yielding uniform and durable coatings. The study examined these catalytic structured materials (CSMs) for their performance in methanol steam reforming.

In 2021, Idriss published a manuscript outlining that an assignment commonly utilized in catalyst research is not feasible. Despite this, the idea that you can measure oxygen vacancies (OV) with ex situ x-ray photoelectron spectroscopy (XPS) persists. A review of 427 manuscripts citing Idriss’s work found that for the citations related to catalysis (55%), those with an interest in OV were more likely to avoid using XPS to identify OV. Regardless, many catalysis researchers continue to rely on erroneous application of XPS data. Of the citations not related to catalysis research (45%), these were more likely to utilize the more obscure approaches. Surprisingly, two thirds of the citations showed no apparent interest in the assignment, an observation shared between both groups. We believe that many of these citations have failed to understand the original publication and/or are using it as a general citation for O 1s assignments. When the data were viewed as a function of publication year, three observations were made: (1) The number of citations using XPS for OV is increasing, (2) those utilizing it as a direct measure are decreasing, and (3) one alternative method is gaining popularity. Herein, we provide evidence that most approaches are generally not applicable, or if they are, can only be successfully performed in-operando using highly specialized equipment with carefully planned methodologies; less than 3% of the citations reviewed met these criteria. It is envisaged that this publication will assist in improving the quality of XPS data interpretation in relation to XP O 1s spectroscopy.

Bimetallic Ni–Fe configurations can influence catalyst performance in plasma catalytic CO₂ methanation, highlighting the importance of metal–metal interactions and catalyst design.

In an interview in 1982, which was 1 year after he shared the Nobel Prize, Kai Siegbahn was asked about his opinion regarding the name of the technique he had developed. Siegbahn had named it “electron spectroscopy for chemical analysis” (ESCA), but the community was choosing to call it “X‐ray photoelectron spectroscopy” (XPS). Now, more than 40 years later, 20 XPS experts have given their opinions on Siegbahn's response and the name of the technique. Some of these participants have been doing XPS for many years and have provided a historical perspective on this issue. While there is no call in these comments for the community to return to “ESCA”—“XPS” is regarded as a more than an adequate name, and insisting on a name change at this point in time would probably only create confusion. However, some of the participants of this study still consider “ESCA” to be an acceptable way to refer to the technique, especially when it is used in a chemical context.

A facile method of synthesizing flexible thin films of carbon nano dots (CNDs) and Polyvinyl Pyrrolidone (PVP) on cellulose based substrates is developed and their thermoelectric properties are demonstrated through the fabrication of a wearable device. Alongside enhanced thermoelectric performance, the CND thin films are biocompatible, low cost and scalable, all essential criteria for wearable thermoelectric devices. A critical window of the CND loading concentration on the cellulose‐based substrate is observed, with significantly enhanced Seebeck coefficient and Power Factor of thin films, demonstrating that the trade‐off principles for thermoelectric materials must be carefully tuned. The highest Seebeck coefficient of –358.45 µV·K⁻¹, power factor of 0.03 µW·m⁻¹·K⁻² and the lowest thermal conductivity of 0.086 W·m⁻¹·K⁻¹ at room temperature is achieved with a CND loading concentration of 9.32 g cm⁻². A wearable thermoelectric device is fabricated using n‐type CND films with copper electrodes. When worn, the device can generate voltage and current of ≈70 mV and ≈15 nA, respectively, at ΔT of 10 K.

This study considers how poor x-ray photoelectron spectroscopy (XPS) peak fitting in the scientific literature is both affected by previous precedent and affects future published work. It focuses on a highly cited paper (the “Subject” paper) from a respected journal that contains incorrect S 2p peak fits. This paper was studied in a genealogical fashion vis-à-vis the XPS peak fitting in its “child,” “parent,” “grandparent,” and “great-grandparent” papers. Interestingly, precedents were not followed to a high degree between parent and child papers. However, in many cases, even when the authors of a study did not follow the incorrect precedent that they cited, they still incorrectly fit their data. Thus, not necessarily for good reasons, the effects of poor XPS peak fits on future generations of papers may be less than some experts had expected or feared. In many cases, older papers appear to contain better XPS peak fitting than newer ones.

In this paper, a review of the analysis of Fe 2p3/2 peak and other transition metals in the austenitic stainless steel literature is presented. It reveals the significant shortcomings of the most widely used approaches, based on the principle of “chemistry fitting,” where single symmetric peaks are used to represent either individual oxidation states or specific compounds. No meaningful conclusions can be drawn from these commonly employed two- or three-component peak fitting (2C and 3C) approaches; the implication being that a large portion of the literature that relies on this approach is flawed. As a significantly more accurate and reliable alternative to “chemistry fitting,” we also assess “envelope fitting” (using empirical multiplet structures) and examine its limitations when applying the approach to austenitic stainless steel data. A detailed comparison of these two fitting approaches is described in Part I. For other elements such as Cr 2p, the problems associated with using single components to represent oxidation states or compounds are not as severe. It was found that it does not impact binding energy measurements, but does influence relative intensities, which will have a flow-on effect for oxide thickness calculations and obtaining a correct understanding of the surface more broadly.

Analyzing transition metal XPS peaks is widely used to determine surface composition and chemistry. However, these peaks have a complex structure, which is still the subject of investigation. Fe 2p analysis is a case in point where the multiplet structure and many-electron-effects lead to peak shapes that cannot be analyzed using standard approaches. Examination of the literature reveals that one of the most widely used approaches to data reduction when processing Fe 2p3/2 spectra involves using symmetric two- or three-component peak fitting with each peak effectively acting to capture a single chemical species (chemistry fit) in the complex spectra. Herein, this approach is compared to an envelope fit approach using Biesinger multiplet components of known iron oxides to determine how effective these methods are in reproducing iron oxide composition. Mixed oxide and metal XPS Fe 2p spectra were synthesized using reference spectra collected experimentally. For the first time, the accuracy and differences between the two approaches are reported. It is demonstrated that no meaningful conclusions can be drawn using single symmetric peaks to analyze complex Fe 2p3/2 spectra, implying that a large portion of the literature is flawed. The envelope fit approach, however, is shown to provide useful information regarding oxide ratios in mixed iron oxide materials, though limitations do exist. A methodology for evaluating the quality of XPS analysis of Fe 2p3/2 spectra is proposed for benchmarking new submissions so that reviewers, authors, and editors can assess these submissions.

Designing effective antifog coatings poses challenges in resisting physical and chemical damage, with persistent susceptibility to decomposition in aggressive environments. As their robustness is dictated by physicochemical structural features, precise control through unique fabrication strategies is crucial. To address this challenge, a novel method for crafting nanoscale antifog films with simultaneous directional growth and cross–linking is presented, utilizing solid‐state continuous assembly of polymers via ring‐opening metathesis polymerization (ssCAP _ROMP ). A new amphiphilic copolymer (specified as macrocross–linker) is designed by incorporating polydimethylsiloxane, poly(2‐(methacryloyloxy)ethyl) trimethylammonium chloride (PMETAC), and polymerizable norbornene (NB) pendant groups, allowing ssCAP _ROMP to produce antifog films under ambient conditions. This novel approach results in distinctive surface and molecular characteristics. Adjusting water‐absorption and nanoscale assembly parameters produced ultra‐thin (≤100 nm) antifog films with enhanced durability, particularly against strong acidic and alkaline environments, surpassing commercial antifog glasses. Thickness loss analysis against external disturbances further validated the stable surface‐tethered chemistries introduced through ssCAP _ROMP , even with the incorporation of minimal content of cross–linkable NB moieties (5 mol%). Additionally, a potential zwitter‐wettability mechanism elucidates antifog observations. This work establishes a unique avenue for exploring nanoengineered antifog coatings through facile and robust surface chemistries.