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Hydrothermal synthesis of earth-abundant electrocatalysts for PEM water electrolysis
No full textIntroduction
Hydrogen gas (H2) has the potential to be a sustainable energy carrier, as it has a high energy density, does not release CO2, and is a feedstock chemical in various industries. Unfortunately, H2 is mainly produced from fossil fuels by steam methane reforming, naphtha reforming, and coal gasification.[1], [2] A promising alternative is water splitting through electrolysis, which produces H2 and O2 via the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER), respectively. As a major advantage, this method does not release CO2 or other volatile by-products. Commercial water electrolysis methods are alkaline electrolysis and PEM (proton exchange membrane) electrolysis. The advantages of PEM electrolysis are higher energy efficiency, quick response, and scalability. However, the used catalysts for the HER and OER in PEM electrolysis are Pt and IrO2, respectively, which are both expensive and low-abundance materials.[3]
Methodology
In the CLEANH2 project, we tackle these challenges. The aim of this PhD is to select, synthesize, characterize, and evaluate earth-abundant electrocatalysts for both HER and OER. The focus is on metal sulfides for HER and metal oxides for OER. Molybdenum disulfide (MoS2) is a widely known alternative catalyst for the HER due to its high catalytic activity and high stability.[4] Other sulfides such as Fe sulfides, were also found to be active as HER catalysts.[5] This implies that a whole range of mixed metal sulfides may have a catalytic performance and stability that outperforms the more established materials. Finding an earth-abundant alternative for the OER is much more challenging. This is caused by the difficult kinetics of the OER and the strong oxidative and acidic environment on the OER side of PEM electrolyzer.[6] A material is needed that has good catalytic activity for the OER and is stable against oxidation in acidic environments. Therefore, metal oxides with more abundant metals were selected as replacements for IrO2.
Discussion
These materials were synthesized via hydrothermal synthesis routes. The synthesized materials were characterized using X-ray diffraction (XRD), Raman spectroscopy, and scanning electron microscopy (SEM) to investigate their morphology and crystal structure. The catalytic performances of the synthesized materials were evaluated with linear sweep voltammetry (LSV) using a three-electrode cell.
Conclusions
In our study, we have explored the potential of earth-abundant electrocatalysts for hydrogen production. Our initial choice of Fe2(MoO4)3 for the oxygen evolution reaction did not yield the expected catalytic activity. Nevertheless, the synthesized Fe and Mo sulfides have demonstrated promising catalytic activity for the hydrogen evolution reaction. We will continue our search for alternative materials for the oxygen evolution reaction and further evaluate the stability and efficiency of these promising Fe and Mo sulfides. As we progress, we are optimistic about the potential impact of our research on the advancement of clean and sustainable energy technologies.
References
[1] J. D. Holladay, J. Hu, D. L. King, and Y. Wang, “An overview of hydrogen production technologies,” Catalysis Today, vol. 139, no. 4. pp. 244–260, Jan. 30, 2009. doi: 10.1016/j.cattod.2008.08.039.
[2] D. A. J. Rand, “A journey on the electrochemical road to sustainability,” Journal of Solid State Electrochemistry, vol. 15, no. 7–8. pp. 1579–1622, Jul. 2011. doi: 10.1007/s10008-011-1410-z.
[3] E. B. Agyekum, C. Nutakor, A. M. Agwa, and S. Kamel, “A Critical Review of Renewable Hydrogen Production Methods: Factors Affecting Their Scale-Up and Its Role in Future Energy Generation,” Membranes, vol. 12, no. 2. MDPI, Feb. 01, 2022. doi: 10.3390/membranes12020173.
[4] R. Li et al., “Recent advances in MoS2-based materials for electrocatalysis,” Chemical Communications, vol. 58, no. 14, pp. 2259–2278, Feb. 2022, doi: 10.1039/d1cc04004a.
[5] D. Heift, “Iron sulfide materials: Catalysts for electrochemical hydrogen evolution,” Inorganics, vol. 7, no. 6. MDPI Multidisciplinary Digital Publishing Institute, 2019. doi: 10.3390/INORGANICS7060075.
[6] X. K. Gu, J. C. A. Camayang, S. Samira, and E. Nikolla, “Oxygen evolution electrocatalysis using mixed metal oxides under acidic conditions: Challenges and opportunities,” Journal of Catalysis, vol. 388. Academic Press Inc., pp. 130–140, Aug. 01, 2020. doi: 10.1016/j.jcat.2020.05.008
Filgotinib in action: Real-world insight from a Belgian registry of patients with rheumatoid arthritis
No full textGalapago
Environmental impact assessment for the recycling of phosphogypsum in alternative cementitious binders
No full textWhy does tinnitus vary with naps? A polysomnographic prospective study exploring the somatosensory hypothesis
No full textBackground: Tinnitus, defined as the conscious awareness of a noise without any identifiable corresponding external acoustic source, can be modulated by various factors. Among these factors, tinnitus patients commonly report drastic increases of tinnitus loudness following nap sleep. Previous studies have suggested that this clinical pattern could be attributed to a somatosensory modulation of tinnitus. To our knowledge, no polysomnographic study has been carried out to assess this hypothesis. Methods: For this observational prospective study, 37 participants reporting frequent increases of tinnitus following naps were recruited. They participated to six full-polysomnography nap attempts over two days. Audiological and kinesiologic tests were conducted before and after each nap attempt. Results: 197 naps were collected. Each nap at each time of day elicited an overall significant increase in tinnitus minimum masking level (MML). Each inter nap period elicited an overall significant decrease. Tinnitus modulations were found significantly correlated with nap sleep duration (Visual numeric scale on tinnitus loudness, VNS-L, p < 0.05), with snoring duration (MML, p < 0.001), with snoring average sound level (VNS on tinnitus intrusiveness, VNS-I, p < 0.05) and with sleep apnea count (VNS-I, p < 0.001). Conclusions: This study confirms objectively that tinnitus may increase following naps. No association was found between these modulations and somatosensory modulations involving the temporomandibular joint and cervical areas. However, it may be possible that nap-induced tinnitus modulations are a hidden form of somatosensory modulation as snoring and sleep apnea events are often related to tensor veli palatini muscle dysfunction.The authors would like to thank Mr Louis Korczowski for his contribution in the realization of the Tinnitus-n-Sleep github repository that was used for labeling bruxism events and for his role as founder of Siopi. Similarly, the authors would like to warmly thank FranceAcouph`enes and the Siopi mobile app team for their help to recruit subjects for the study. The authors would like to thank Mrs Charlotte Glabasnia Linck for her contribution of independently scoring a second time the sleep apnea events of the nap recordings, as presented in the supplementary Table 3
Enhancing education through learning for sustainability: an explorative review of broader benefits
No full textNot availableDirectorate-General for Education, Youth, Sport and Culture Directorate A — Policy Strategy and Evaluation Unit A.4 — Evidence-Based Policy and Evaluatio
Chemotherapy-Induced Cell-Surface GRP78 Expression as a Prognostic Marker for Invasiveness of Metastatic Triple-Negative Breast Cancer
No full textMetastasis remains the leading cause (90%) of cancer-related mortality, especially in metastatic triple-negative breast cancer (TNBC). Improved understanding of molecular drivers in the metastatic cascade is crucial, to find accurate prognostic markers for invasiveness after chemotherapy treatment. Current breast cancer chemotherapy treatments include doxorubicin and paclitaxel, inducing various effects, such as the unfolded protein response (UPR). The key regulator of the UPR is the 78-kDa glucose-regulated protein (GRP78), which is associated with metastatic disease, although, its expression level in the context of invasiveness is still controversial. We evaluate doxorubicin effects on TNBC cells, identifying GRP78 subpopulations linked to invasiveness. Specifically, we evaluate the motility and invasiveness of GRP78 positive vs. negative cell subpopulations by two different assays: the in vitro Boyden chamber migration assay and our innovative, rapid (2-3 h) clinically relevant, mechanobiology-based invasiveness assay. We validate chemotherapy-induced increase in the subpopulation of cell-surface GRP78(+) in two human, metastatic TNBC cell lines: MDA-MB-231 and MDA-MB-468. The GRP78(+) cell subpopulation exhibits reduced invasiveness and metastatic potential, as compared to whole-population control and to the GRP78(-) cell subpopulation, which are both highly invasive. Thus, using our innovative, clinically relevant assay, we rapidly (on clinical timescale) validate that GRP78(-) cells are likely linked with invasiveness, yet also demonstrate that combination of the GRP78(+) and GRP78(-) cells could increase the overall metastatic potential. Our results and approach could provide patient-personalized predictive marker for the expected benefits of chemotherapy in TNBC patients and potentially reveal non-responders to chemotherapy while also allowing evaluation of the clinical risk for metastasis.Acknowledgments
The authors thank Julia Lipovetsky for the technical assistance. The work was partially supported by the Israeli Ministry of Innovation, Science and Technology (MOST) Breakthrough Research Program (Grant no. 1001717860 awarded to Professor Daphne Weihs), by the Applebaum Foundation, by the Gerald O. Mann and the Frank and Dolores Corbett Charitable Foundations, and by the Russel Berrie Nano Institute at the Technion-IIT (all awarded to
Professor Daphne Weihs).
Funding
Open access funding provided by Technion - Israel Institute of Technology
A lab approach to Simulate the Effects of Thermoforming on the Gas Permeability of Commercial Multilayers
No full textIn the search for sustainable food packaging, critical reflection on the choice, combination and quantity of (bio)materials for specific applications is becoming increasingly important to prevent food waste. Our previous research has shown the combined effects of material thinning and polymer reorientation on the gas permeability of thermoformed multilayer trays. This study aims to investigate the feasibility of simulating the thermoforming process by heating and deforming (bio)plastic multilayers in a lab scale set-up to determine the maximum thinning and the associated gas permeability properties.
First, thermal and tensile properties of commercial PE/EVOH/PE and ecovio®/G-Polymer/ecovio multilayer films (~85 μm) are characterized. Next, tensile testing at selected temperatures is applied to determine the maximum stretch, based on the elongation at break. Then, hot stretching of 70x60 mm2-films in machine and/or cross direction (MD, CD, MD+CD) or 45°, is done in an oven at optimal temperature by applying maximum gravity without breaking the multilayer. The microscopical thickness resulting from these situations is compared with the thinning in the bottom, walls and corners of thermoformed trays. The results show that thinning of both films is proportional to an increase in the water vapor transmission rate (WVTR), with the PE-layers providing a better water vapor barrier than the ecovio-layers. In contrast, the oxygen transmission rate (OTR) is not proportional to thinning of the total film, nor the thickness of the barrier layer. Here, polymer reorientation comes into play, even resulting in improved oxygen permeability coefficients as compared to the base films.
We conclude that this approach can support the optimization of thermoforming processes by determining the maximal stretch of the individual layers while safeguarding the gas barrier properties of the final packaging, e.g. in thermoformed fiber-based trays.confidentia
Air pollution exposure and incidence of cardiometabolic diseases: Exploring the modifying role of dietary antioxidant intake in adults
No full textWhile the antioxidative potential of certain vitamins and minerals in cardio-protection has garnered increasing interest, their ability to attenuate associations between air pollution exposure and cardiometabolic diseases (CMDs) remains unexplored. This study examined the associations of air pollution (particulate matter including ultrafine particles (UFP), and nitrogen oxides, including NO2 and NOx) and six dietary antioxidants with incident non-fatal CMDs in 30,519 EPIC-NL study participants. Data on CMD incidence (total cardiovascular disease (CVD), acute myocardial infarction (AMI), coronary heart disease (CHD) and heart failure (HF)) and Type 2 Diabetes Mellitus (T2DM) diagnoses were obtained from medical registries. Annual average ambient concentrations of air pollutants at the participants' baseline residential addresses were predicted using land use regression models. Dietary intake of antioxidants was assessed via a food frequency questionnaire. Multivariable Cox regression models were used to explore associations. Exposures to NO2 and UFP were associated with elevated HF risk (Hazard Ratio (HR) (95 % CI): 1.24 (1.00, 1.54) and 1.69 (1.04, 2.76), respectively). Higher beta-carotene intake was associated with reduced risk of total CVD and CHD incidence (HR (95 % CI): 0.94 (0.89, 0.99) and 0.92 (0.84, 0.99), respectively), whereas, in general, antioxidant intake was positively associated with incident T2DM. Interaction analyses indicated some variability in CMD risk by antioxidant intake, but none of these interactions remained significant after correcting for multiple comparisons. These findings indicate that the associations of air pollution with incident CMD do not differ by dietary antioxidant intake.The EPIC-NL study was funded by “Europe against Cancer” Program of the European Commission (DG SANCO); the Dutch Ministry of Public Health, Welfare and Sports (VWS); the Netherlands Organization for Health Research and Development (ZonMw); and the World Cancer Research Fund (WCRF). The present study has received funding from the European Union’s Horizon 2020 research and innovation program ‘SURREAL’ under grant agreement No 956780. TSN holds funding by Methusalem. IV and EJT are supported by an NWO Gravitation Grant (Exposome-NL, 024.004.017). The funding bodies had no role in the study design, the collection, analysis and interpretation of the data, in writing of the manuscript and in the decision to submit the manuscript for publication
Understanding the Impact of Automatic and Deliberate Mental Haptic Imagery on Consumer Touch Perception in E-commerce Environments
No full textThe phenomenon's relevance. In online stores, the absence of physical product inspection often leads to post-purchase disappointment. Lacking technologies for engaging other senses, webshops mainly rely on visual information. To fill out the blanks, consumers can also rely on 'mental imagery' while browsing, imagining how it would be to interact with products through all senses. Theoretical foundations. Eliciting mental imagery has been used as a persuasive communication strategy for years. Especially in advertising, consumers are often encouraged to imagine the use of the product, leading to better product evaluation, stronger product desire, and greater purchase intentions (Krishna et al., 2016; Elder & Krishna, 2012). Two types of mental sensory imagery can be distinguished: deliberate (i.e., consumers being instructed to form an image) and automatic mental imagery (i.e., more spontaneous imagination, for example, by reading a description). The effects of both types of imagery are so far mostly studied in isolation (Elder & Krishna, 2022). Potential contributions to the field. This research (1) examines the effect of haptic imagery on consumer reactions in webshops, while (2) comparing both types (i.e., automatic and deliberate mental imagery). Research question(s). Our objective is to develop a better understanding of the role of these two types of haptic imagery in consumer decision-making processes in online shopping. We unravel explanatory mechanisms and inspect boundary conditions. Methodology. A controlled lab experiment (n = 161) in a beauty care context with a 2 (automatic imagery: yes/no) x 2 (deliberate imagery: yes/no) full factorial design has been conducted. Mediators (e.g., processing fluency), as well as moderators (e.g., imaginativeness), have been considered. Findings. Consumers with high imaginativeness should be encouraged to use their imaginative power by appealing to deliberate (rather than automatic) mental haptic imagery, as this activates three underlying favorable mechanisms. The indirect effect of deliberate imagery (compared to automatic imagery) on consumer attitude towards the product was statistically significant and positive-albeit only for highly imaginative consumers (+1SD)-and this via (1) communication evoked imagery processing (β = .25; 95% CI = [.05, .49]), (2) embodied mental simulation (β = .18; 95% CI = [.03, .36]), and (3) processing fluency (β = .21; 95% CI = [.05, .42]). These three mechanisms, in turn, are also directly positively related to more positive attitudes and higher purchase intentions towards the product. Discussion. Our findings in a webshop context echo what has been observed in the advertising realm before. Moreover, by examining both types of haptic imagery concurrently (rather than separately), we were able to observe that for certain target customer segments, deliberate imagery outperforms automatic imagery. Conclusion. These insights can inform marketing strategies and practices, ultimately leading to more effective and satisfying online shopping experiences for consumers
Relative quantification of proteins and post-translational modifications in proteomic experiments with shared peptides: a weight-based approach
No full textMotivation Bottom-up mass spectrometry-based proteomics studies changes in protein abundance and structure across conditions. Since the currency of these experiments are peptides, i.e. subsets of protein sequences that carry the quantitative information, conclusions at a different level must be computationally inferred. The inference is particularly challenging in situations where the peptides are shared by multiple proteins or post-translational modifications. While many approaches infer the underlying abundances from unique peptides, there is a need to distinguish the quantitative patterns when peptides are shared.Results We propose a statistical approach for estimating protein abundances, as well as site occupancies of post-translational modifications, based on quantitative information from shared peptides. The approach treats the quantitative patterns of shared peptides as convex combinations of abundances of individual proteins or modification sites, and estimates the abundance of each source in a sample together with the weights of the combination. In simulation-based evaluations, the proposed approach improved the precision of estimated fold changes between conditions. We further demonstrated the practical utility of the approach in experiments with diverse biological objectives, ranging from protein degradation and thermal proteome stability, to changes in protein post-translational modifications.Availability and implementation The approach is implemented in an open-source R package MSstatsWeightedSummary. The package is currently available at https://github.com/Vitek-Lab/MSstatsWeightedSummary (doi: 10.5281/zenodo.14662989). Code required to reproduce the results presented in this article can be found in a repository https://github.com/mstaniak/MWS_reproduction (doi: 10.5281/zenodo.14656053).This work was supported by the National Science Centre, Poland [grant Preludium 2020/37/N/ST6/04070 to M.S.]