Research Articles (Chemistry)
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Item Simultaneous trifunctional group passivation using imidazole derivatives for enhanced performance of perovskite solar cells(Elsevier Ltd, 2025) Iwuoha, Emmanuel; Yang, Jun; Niu, QiaoliPerovskite solar cells (PSCs) are one of the most promising energy technologies in the field of renewable energy. The solution-based perovskite film-forming method is one of its important advantages in commercialization. However, the polycrystalline perovskite thin films prepared by this method may also exhibit various defects, leading to a decrease in device performance. In this work, an imidazole derivative 1-(2-hydroxyethyl)-3-methylimidazolium chloride (HMCl) was used as a passivator for perovskite thin films. The imidazole moiety and hydroxyl in HMCl passivated the negatively charged I - and positively Pb2+ defects in CH3NH3PbI3 (MAPbI3), respectively. Meanwhile the chloride ion establishes ionic bonds with uncoordinated Pb2+, further enhancing the passivation of defects. With HMCl, the PCE of the PSC was enhanced from 17.53 % of the control device to 19.71 %. In addition, the introduction of HMCl enhanced the hydrophobicity of perovskite films, and therefore, improved the storage stability of PSCs. This study provides an alternative passivator for the development of highperformance and long-term stable PSCs.Item Sustainable gliadin - metal oxide composites for efficient inactivation of Escherichia coli and remediation of cobalt (II) from water(Elsevier ScienceDirect Journals, 2024) Emile Salomon Massima Mouele; Leslie PetrikBio-based materials facilitate greener approach to engineering novel materials with multifunctional properties for various applications including water treatment. In this study, we extracted gliadin from wheat gluten using alcoholic solvent. The aggregation limitations of gliadin protein were overcome by functionalisation with metal oxides (MOs) TiO2, AgFe2O3 and AgFe–TiO2 prepared by chemical precipitations. The novel composites were characterised by scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS), Fouriertransform infrared spectroscopy (FTIR), X-Ray diffraction (XRD), thermogravimetry analysis (TGA), Brunauer Emmet–Teller (BET), and zeta potential. The multifunctionality of MOs-gliadin composites was tested through toxic Escherichia coli (E. coli) inactivation and Co2+ adsorption from water. The antibacterial results showed excellent inhibition under both dark and light conditions. The maximum Co2+ uptake, 101 mg/g was reached with TiO2@gliadin after 24 h and best fitted the Langmuir isotherm model. The adsorption process followed pseudo-second order model with an equilibrium adsorption capacity, qe2 = 89.86 mg/g closer to the experimental data. Thermodynamic investigations indicated that ΔG◦ = − 9.677 kJ/mol, ΔH◦ = − 123 kJ/mol, and ΔS◦ = 0.490 J.K/mol, respectively, suggesting that adsorption was spontaneous and endothermic. The regenerated TiO2@gliadin composite was still efficient after five consecutive cycles. This study demonstrates that MOs-gliadin blended composites are sustainable for water purificationItem Stability, deactivation and regeneration study of a newly developed HZSM-5 and Ni-doped HZSM-5 zeolite catalysts for ethanol-to-hydrocarbon conversion(Elsevier B.V., 2024) Anekwe, Ifeanyi Michael Smarte; Khotseng, LindiweThis work investigates the stability and regeneration of HZSM-5 and Ni/HZSM-5 catalysts in the ethanol-to-hydrocarbon conversion. The catalysts were characterised using different techniques and evaluated at 623 K and 7 h−1 for 96 h TOS with two regeneration cycles. HZSM-5 showed high stability with 100% ethanol conversion, while Ni/HZSM-5 catalysts maintained 100% stability for 48 h before dropping. Regenerated catalysts were comparable to the originals in terms of product distribution, stability, and performance. HZSM-5 preferred BTX, while Ni-doped catalysts favoured C5-C8, C9-C12, and C12+ synthesis. The regeneration process restored catalytic activity, especially for the Ni-doped catalysts, extending their life and reducing replacement costs.Item Electrical environment can be altered at 1 km distances from high voltage power lines.(Institute of Physics, 2024) Matthews, James C.; Shallcross, Dudley EHigh voltage powerlines emit electrical charges into the atmosphere which can then attach to aerosols. This space charge above ground can be measured directly using ion spectrometers or indirectly through perturbations of the Earth's potential gradient using field mills. Several publications are reviewed to find evidence of aerosol charging at a distance from power lines. Field measurements of charge state near to high voltage power lines selected due to their high emissions of ions measured a small positive enhancement of electrical charge on aerosols at distances greater than 300 m, corresponding to a transit time of up to 400 s A quasi one-dimensional model of ion-aerosol interactions from a high voltage powerlines found that the addition of new ions to an aerosol population will result in those ions transferring charge to the aerosol which would then remain the dominant carrier of charge several hundred meters downwind. 10-min PG measurements from a fixed site measuring in 2008 compared measurements when the site was downwind of a 275 kV powerline to times with no wind and found evidence of space charge overhead through greater fields and variability at distances over 800 m These studies combined show evidence that the electrical environment near to power lines can be altered beyond 1 km from AC high voltage power lines, with excess charges likely to be concentrated on aerosol.Item Air mass flow and pressure optimization of a pem fuel cell hybrid system for a forklift application(Multidisciplinary Digital Publishing Institute (MDPI), 2024) Radica, Gojmir; Lototskyy, Mykhaylo V.; Pasupathi, SivakumarThe air compressor holds paramount importance due to its significant energy consumption when compared to other balance of plant components of polymer electrolyte membrane (PEM) fuel cells. The air supply system, in turn, plays a critical role in ensuring the stable and efficient operation of the entire fuel cell system. To enhance system efficiency, the impact of varying the stoichiometric ratio of air and air pressure was observed. This investigation was carried out under real loading conditions, replicating the conditions experienced by the power module when fuel cells are in use within a forklift. The air compressor can be operated at different pressure and excess air ratios, which in turn influence both the fuel cell’s performance and the overall efficiency of the power module system. Our research focused on assessing the performance of PEM fuel cells under different load cycles, adhering to the VDI60 requirements for forklift applications. This comprehensive examination encompassed the system’s minimum and maximum load scenarios, with the primary goal of optimizing excess air and pressure ratio parameters, especially under dynamic load conditions. The results revealed that higher air pressures and lower excess air ratios were conducive to increasing system efficiency, shedding light on potential avenues for enhancing the performance of PEM fuel cell systems in forklift applications.Item Smart worksheets and their positive impact on a first-year quantitative chemistry course(American Chemical Society, 2025) Shallcross, Dudley Edmund; Davies-Coleman, Michael; Lloyd, ChrisThe pandemic was a very difficult time for everyone, as well as teachers and their students. Teachers of first-year quantitative chemistry courses, both during the pandemic and postpandemic, encountered many pandemic-induced difficulties, including inter alia communicating with individual students, providing them with rapid formative feedback, and determining where they were on their learning journey. In addition, two cohorts of students requiring different teaching approaches were enrolled on this course during the period of this study (2020-2023). One cohort had a post-16 mathematics qualification (A-level that includes calculus) and the other, a pre-16 mathematics qualification (GCSE that does not include calculus) as their highest mathematics qualification. In this Article, we show the value of using Smart Worksheets to address these challenges. The Smart Worksheets provided valuable information about the students’ ability to apply mathematical concepts within a chemistry context and, consequently, allowed the teaching team to shape workshops to cater for any application difficulties. Smart Worksheets clearly identified a number of (basic) skills that many of the students were struggling with, including graphing, uncertainty analysis, application of units, and application of logs to buffer calculations. Smart Worksheets also allowed the teaching team to connect with students, to either commend them on their work or ask how they were coping if they appeared to be struggling. Students highlighted how the instant formative feedback provided by Smart Worksheets and their unlimited availability during the course impacted positively on their learning. The Smart Worksheets also helped to identify two subgroups in the student cohort with the higher mathematics qualification; one subgroup could apply their mathematics knowledge within different chemistry contexts while the other subgroup was not able to move from a mathematical context to a chemistry context. This information allowed the teaching team to alter workshop approaches to emphasize translation from one context to another.Item Ag doped TiO2 anchored on metal free g-C3N4 for enhanced solar light activated photodegradation of a dye(Elsevier, 2024) Ratshiedana, Rudzani; Mishra, Ajay Kumar; Mafa, Potlako JohnHeterogeneous semiconductor photocatalysis has attracted researcher’s attention in wastewater treatment owing to the improved surface area, optical properties, and charge transfer rate for boosted degradation of organic pollutants. Thus, the g-C3N4/Ag/TiO2 was prepared following a hydrothermal route for the degradation of azo dye tartrazine (TA) used as a food colourant under solar light. Before application, the composite and pristine materials were interrogated for physicochemical and structural properties using SEM, TEM, EDS, XPS, XRD, UV–vis DRS, PL, BET, Raman, and FTIR spectroscopy. The PL and electrochemical analysis revealed that the CNAT composite had a high charge transfer rate that was coupled with low charge carrier complexation. The degradation efficiency of 91 % was realized in 180 min and the rate of pseudo-first-order kinetics of 0.01143 min− 1 was obtained. The CNAT catalyst also displayed high removal efficiency towards a cocktail of naproxen (NPX) and TA. The improved removal efficiencies stem from increased visible usage, reduced charge carrier compounding, and formation of Z-scheme heterojunction with high redox capabilities. The total organic carbon removal reached 95 % while CNAT showed high convincing stability even after four cycles. Given the above results, the hydrothermally prepared composite catalyst can be extended to other organic pollutants such as pharmaceuticals, pesticides, and reduction of inorganics.Item Ag induced plasmonic tio2 for photocatalytic degradation of pharmaceutical under visible light: insights into mechanism, antimicrobial and cytotoxicity studies(Elsevier, 2024) Ratshiedana, Rudzani; Mishra, Ajay Kumar; Malefane, Mope EdwinGlobal concerns include water scarcity and shortage, which are escalated by organic pollutants such as naproxen (NPX) that deteriorate drinking water and taint access to safe drinking water by humans. Moreover, NPX may cause gastrointestinal difficulties, cardiovascular risks, kidney damage, allergic reactions, liver toxicity, bleeding issues and pregnancy risks, hence it is essential to remove it in water. Ag-TiO2 was synthesized by hydrothermal method for NPX degradation. Ag on TiO2 reduced the band gap and surface area of TiO2 and resulted in a plasmonic Ag-TiO2 composite of 0.2 % Ag. The photocatalytic degradation of 0.2 % Ag-TiO2 was 80 % in 180 minutes using a solar simulator during NPX degradation with a first order reaction rate that was 3.6 times faster than that of pure TiO2 and the catalyst showed good stability for four cycles. The dual activity of Ag0 surface plasmon resonance improved light absorption capability and enhanced charge transfer for increased photodegradation rate and stability. The antibacterial studies demonstrated that 0.2 % Ag-TiO2 posted strong antibacterial properties under light irradiation and less in the dark, with a greater effect on gram-negative than gram-positive bacteria. The minimum inhibitory concentration (MIC) values of 620, 1250, 2500, 2500 µg/mL were attained against B. subtilis, S. aureus, E. coli and S. typhimurium bacteria, respectively. The low cell toxicity of 0.2 % Ag-TiO2 was determined using human embryonic kidney (HEK293) cells with an inhibitory concentration (IC50) of 61.09 ± 0.24 µg/mL under light irradiation. Radical trapping experiments demonstrated that hydroxyl radicals (OH• ) played a vital role during the degradation and bactericidal activity of NPX under light irradiation. This work advances new insights on the synthesis of less toxic nanoparticles with high photocatalytic and bactericidal activity for possible applications at industrial scale.Item Uric acid signal transduction enhancement through the electrical wiring of urate oxidase with copper schiff base complex and reduced graphene oxide(Elsevier Ltd, 2025) Moeketse, Teboho; Baker, Priscilla; Makgwane, PeterUric acid (UA) is an important antioxidant biomolecule and disease biomarker in body fluids such as urine, sweat, serum, and saliva. In this paper, we developed an electrochemical biosensor to enhance UA signals using glassy carbon electrodes (GCEs) modified with graphene oxide, copper Schiff base complex and uricase enzyme. The reduced graphene oxide modified sensor took the lead by enhancing the UA signal response when coupled to Schiff base complex modified electrodes. The uricase enzyme biosensor yielded an extended linear range due to its catalytic effect on the UA oxidation process. The development of the sensors involved a step-by-step evaluation of the sensor performance using scanning mode and fixed potential mode electrochemistry, as well as spectroscopic and microscopic techniques. Square wave voltammetry in particular reported UA signal response in the linear range was 12 µM to 167 + µM, and LOD was in the range of 0.26 – 2.54 µM for UA sensors. This information is valuable for sensor application in human biofluids where UA concentrations may manifest up to 150–450 µM.Item Electrochemical analysis of solvothermally synthesized MoS2 nanostructures for high performance supercapacitor(Elsevier Ltd, 2025) Mishra, Ajay Kumar; Kumar, Sunil; Bulla, MamtaThis study investigates the influence of different solvents, including ethylene glycol (EG), dimethylformamide (DMF) and water, on the structure and electrochemical properties of MoS2 synthesized via a single-step pot synthesis technique. These solvents facilitate the formation of MoS2 nanostructures with diverse dimensions. The synthesized material was analyzed using XRD, FTIR, Raman spectroscopy, FE-SEM and BET analysis. The hierarchical microflower structure of MoS2, with exfoliated edge-enriched nanosheets, exhibited the highest specific capacitance of 428 F g−1 at 1 mV s−1 and 280 F g−1 at 1 A g−1 when synthesized using water as a solvent, surpassing the results achieved with other solvents. The MoS2 nanostructure-based symmetric supercapacitor achieved an energy density of 7.5 Wh kg−1, a power density of 1980 W kg−1 and retained ∼95 % capacitance after 1000 cycles at 2 A g−1, highlighting its potential for future applications with exceptional stability and durability.Item Coal fly ash and acid mine drainage-based fe-bea catalysts for the friedel–crafts alkylation of benzene(Multidisciplinary Digital Publishing Institute (MDPI), 2025) Hlatywayo, Tapiwa; Petrik, Leslie; Louis, BenoitCoal fly ash and acid mine drainage are significant environmental issues in South Africa, causing storage constraints and impacting water quality. This study explores the use of coal fly ash and acid mine drainage in preparing zeolite HBEA-supported Fe catalysts. The Na-BEA parent catalysts were synthesised hydrothermally using coal fly ash as a feedstock. The Fe was loaded upon the H-BEA form zeolite using liquid-phase ion exchange or wet impregnation, using Fe-rich acid mine drainage as the metal precursor. The ion-exchanged Fe-BEA catalysts exhibited excellent activity, with the highest selectivity achieved over the 25 AHW after 0.5 h on stream. The study also found that when impregnation was used to load Fe onto the zeolite support, other metals present in the AMD affected the overall activity, with Mn, Ca, Mg, and Na decreasing conversion and selectivity, while Ni had a promoting effect. This study demonstrates that green solid acid catalysts with high catalytic activity can be prepared using two waste materials, coal fly ash and acid mine drainage. To the best of our knowledge, we are reporting for the first time the use of acid mine drainage as a metal precursor in Fe-BEA catalyst preparation.Item Sutherlandiosides E−K: Further cycloartane glycosides from Sutherlandia frutescens(Elsevier Ltd, 2024) Tchegnitegni, Billy Toussie; Lerata, Mookho S.; Beukes, Denzil R.; Antunes, Edith M.A further chemical investigation of the butanol extract of leaves from the South African medicinal plant Sutherlandia frutescens led to the isolation of eight previously unreported saponins (1−8), together with the known sutherlandiosides A−D. Their structures were established by spectroscopic (1D and 2D NMR) analyses, CD, optical rotation, mass spectrometry, as well as chemical conversions. The isolates were screened for their cytotoxic activity against the MCF-7 human breast cancer cell line, although no significant activity was observed. In addition to the chemophenetic markers for this genus, i.e. the cycloartane glycosides, the present work also reports on the first isolation of an oleanan-type saponin from the Sutherlandia genus, forming an important fingerprint for the chemical composition of the plant.Item Chemical science research, elementary school children and their teachers are more closely related than you may imagine: the “I bet you did not know” project(American Chemical Society, 2024) Trew, Alison; Early, Craig; Shallcross, DudleyTopics associated with the chemical sciences form a significant part of the curriculum in science at the primary school level in the U.K. In this methodology paper, we demonstrate how a wide range of research articles associated with the chemical sciences can be disseminated to an elementary school audience and how children can carry out investigations associated with cutting-edge research in the classroom. We discuss how the Primary Science Teaching Trust’s (PSTT’s) “I bet you did not know” (IBYDK) articles and their accompanying Teacher Guides benefit children, primary (elementary) school teachers, and other stakeholders including the researchers themselves. We define three types of research articles; ones describing how children can reproduce the research themselves without much adaptation, others where children can mirror the research using similar methods, and some where an analogy can be used to explain the research. We provide exemplars of each type and some preliminary feedback on articles written.Item Cathodically-activated boron-doped diamond electrode reactor for sensing and analysis of environmental tenofovir and emtricitabine from combination antiretroviral therapy drugs(Elsevier Ltd, 2025) Mokwebo, Kefilwe; Sanga, Nelia; Mini, Sixolile; Cox, Meleskow; Ross, Natasha; Iwuoha, EmmanuelTenofovir disoproxil fumarate (TDF) and emtricitabine (FTC), sold under the brand name Truvada®, are amongst the highly prescribed combination antiretroviral therapy (c-ART) for the treatment and prevention of HIV/AIDS. Herein, for the first time, a simple, selective and rapid electroanalytical approach for the simultaneous co-determination of TDF and FTC on a non-chemically modified boron-doped diamond electrode (BDD) is described. The surface chemistry of the electrode was modified by cathodic pretreatment (CPT) in H2SO4 to generate a CPT-BDD. On a CPT-BDD, TDF and FTC exhibit irreversible oxidation peaks at higher potentials of +1.4 V and +1.65 V, respectively. Comparatively, the voltammetric signal of FTC was not visible on a glassy carbon electrode (GCE). Differential pulse voltammetry (DPV) was able to spatially separate the oxidation peaks of both analytes, and the limit of detection (LOD) of 0.0218 µM and 0.0886 µM were obtained for TDF and FTC, respectively, in the concentration range of 0.1 – 50 µM. The electrochemistry of TDF is pH-dependent, while that of FTC is not at pH>2. Moreover, the signals of TDF and FTC were not affected by the presence of interfering compounds, except for mercury (Hg2+) and lamivudine (3TC). The practicability of this electroanalytical approach was demonstrated by analyzing TDF and FTC in synthetic urine, pharmaceutical formulation and wastewater samples without prior sample pretreatment. The achieved recovery percentages of 93.6 % to 105.7 % demonstrate the practicability of this analytical method in simultaneously monitoring TDF and FTC in real samplesItem Transition metal phosphides for efficient hydrogen evolution: synthesis, multiscale regulation, and industrial prospects(Elsevier Ltd, 2025) Iwuoha, Emmanuel; Dong, Hao; Jiang, JunzhengAchieving scalable green hydrogen generation through water electrolysis hinges on discovering affordable yet highly effective hydrogen evolution reaction (HER) catalysts to replace traditional Pt-based options. Transition metal phosphides (TMPs) have risen as attractive electrocatalysts, featuring tunable electronic structures, excellent conductivity, and robust stability. This review systematically examines recent advances in TMPs-based HER catalysts, bridging fundamental research and industrial applications. We first elucidate structure-activity relationships and HER mechanisms, then critically evaluate scalable synthesis methods. Multiscale optimization strategies are comprehensively discussed, including atomic-scale engineering, nanostructural design, and hybrid composites, with experimental-theoretical correlations quantifying performance enhancements. Notably, we highlight breakthroughs in achieving industrial current densities (≥500 mA cm−2) while maintaining stability. Key challenges in in-situ characterization, durability, and practical deployment are identified, with targeted solutions proposed to accelerate commercialization. This work provides critical insights for designing next-generation HER electrocatalysts to enable sustainable hydrogen production at scale.Item Sensitive gold nanostar-based adsorption sensor for the determination of dexamethasone(Multidisciplinary Digital Publishing Institute (MDPI), 2025) MacDonald, Riccarda Thelma; Pokpas, Keagan; Iwuoha, Emmanuel; Cupido, CandiceHerein, a novel, highly efficient electrochemical adsorption method is introduced for detection of the potent anti-inflammatory synthetic corticosteroid, dexamethasone (DEX). Unlike conventional electrochemical techniques that rely on high reduction potentials, the proposed sensor offers an alternative adsorption-based mechanism with a gold nanostar-modified glassy carbon electrode (AuNS|GCE). This enables DEX detection at a less negative or moderate reduction potential of +200 mV, circumventing potential window limitations of a GCE and providing a suitable microenvironment for detection in biological media. DEX is known to effectively prevent or suppress symptoms of inflammation due to its small applied dosage; however, an overdose thereof in the human body could lead to adverse drug effects such as gastrointestinal perforation, seizures, and heart attacks. Therefore, a sensitive method is essential to monitor DEX concentration in biofluids such as urine. NMGA-capped AuNSs were leveraged to enhance the active surface area of the sensing platform and allow adsorption of DEX onto the gold surfaces through its highly electronegative fluorine atom. Under optimized experimental conditions, the developed AuNS|GCE sensor showed excellent analytical performance with a remarkably low limit of detection (LOD) of 1.11 nM, a good sensitivity of 0.187 µA.nM−1, and a high percentage recovery of 92.5% over the dynamic linear range of 20–120 nM (linear regression of 0.995). The favourable electrochemical performance of this sensor allowed for successful application in the sensitive determination of DEX in synthetic urine (20% v/v in PBS, pH 7).Item Characterization of new pyrone-containing flavones from Helichrysum petiolare Hilliard & B.L. Burtt(Elsevier B.V., 2025) Makhaba, Masixole; Yalo, Masande; Koki, Mkhuseli; Nako, Ndikho; Mabusela, Wilfred T.; Pearce, Keenau; Benjeddou, MongiHelichrysum petiolare Hilliard & B.L. Burtt. (Asteraceae), native to the Cape Floral Region of South Africa, is traditionally used in the management of wounds, respiratory complaints, and diabetes. Although extensive studies on its extracts, few have focused on the bioactivity of the individual phytochemicals. In this study, chromatographic processing of the H. petiolare leaf total extract led to the isolation and identification of ten compounds C1–C10) using NMR, FTIR, and HRESIMS spectroscopy. Two pyrone-containing flavones (C1 and C2) are reported for the first time from natural sources. The known compounds identified included flavonoids (C3–C5), phenolics (C6–C9), and a sterol (C10). The MTT assay revealed dose-dependent cytotoxicity of C1–C4 only against MDA-MB-231 (breast cancer), HeLa (cervical cancer), and HEK-293 (non-cancerous kidney) cell lines after 24 h exposure. Notably, C4 demonstrated selective activity toward HeLa cells (45 % viability reduction at 100 µM; IC₅₀ = 89.19 µg/mL). This is the first report of compounds C1–C10 from H. petiolare and their in vitro cytotoxic profile. Despite moderate activity, this work provides a foundation for further pharmacological investigations of derivatives of these metabolites in cancer management.Item Graphitic carbon nitride (g-C3N4) in fuel cells: A comprehensive review of synthesis, functionalization, and multifaceted electrocatalytic roles(Elsevier Ltd, 2025) Khotseng, Lindiwe; Ravichandran, Balamurali; Zhang, WeiqiThe commercialization of fuel cells hinges on developing low-cost, durable, platinum-group-metal (PGM)-free electrocatalysts. Graphitic carbon nitride (g-C3N4), an earth-abundant polymeric semiconductor, is a promising alternative due to its stability and tunable electronic structure. This review highlights the evolution of g-C3N4 from a material with inherent limitations, such as poor conductivity and low surface area, to a versatile platform for high-performance fuel cell components. We summarize key engineering strategies that overcome these drawbacks, including morphological control, electronic structure modulation via doping and defect engineering, and the formation of synergistic composites. Critically, this work provides a unique and holistic perspective by categorizing the distinct and synergistic electrocatalytic roles of engineered g- C3N4: (i) as a robust catalyst support superior to conventional carbons, (ii) as a potent metal-free catalyst for the oxygen reduction reaction (ORR), (iii) as an ideal scaffold for single-atom catalysts (SACs), and (iv) as a functional membrane additive. Despite significant progress, with performance rivaling platinum in alkaline media, major challenges persist. These include improving activity and stability in acidic environments (e.g. PEMFC) and developing scalable, cost-effective synthesis methods. This work consolidates the current state-of-the-art and outlines future research directions, including the use of advanced characterization and machine learning-assisted design, to realize the full potential of g-C3N4 for a sustainable energy future.Item Metal-organic frameworks and their derivatives as catalysts of magnesium hydrogenation(Institute of Physics, 2025) Lototskyy, Mykhaylo V; Pasupathi, Sivakumar; Linkov, Vladimir MThis article presents the results of an experimental study on the preparation and characterisation of metal-organic frameworks (MOFs) formed by coordination polymers of Ni(II) and Co(II) itaconates (Ni-IA and Co-IA), as well as the products of thermolysis of their mixtures. It is found that the thermolysis results in the formation of heterometallic CoNi nanoparticles enveloped in a porous carbonaceous matrix (CoNi@C core-shell structures). The catalytic effect of the as-synthesised MOFs and their CoNi@C derivatives on the hydrogenation of Mg during high-energy reactive ball milling (HRBM) in hydrogen has been studied. These catalysts were shown to increase the rate of hydrogenation of Mg during HRBM by about ninefold as compared with non-catalysed magnesium. The kinetic improvements are superior to those observed earlier for other catalysts, including Pd-doped UiO-66 MOF and Ni nanoparticles deposited onto graphene-like materials. At the same time, the achieved reacted fractions when using MOFs and their derivatives as catalysts for magnesium hydrogenation were incomplete. It was found that the use of the as-synthesised MOFs as additives to Mg during HRBM results in the slow hydrogenation of pristine magnesium at room temperature during pauses between the first milling sessions. Almost full conversion of Mg into MgH2 was achieved when the milling vial was kept during these pauses until pressure stabilisation. Based on this observation, it was assumed that the intermediate products of MOF decomposition are more active catalysts of magnesium hydrogenation than the CoNi@C core-shell structures formed as the final MOF decomposition product.Item Leveraging TikTok to enhance understanding and engagement in university chemistry students: A South African case study(Taylor and Francis Ltd., 2025) Ross, Natasha; Sulliman, Basheerah; van Heerden, MartinaThis study explores TikTok’s potential as an educational tool in South African undergraduate chemistry education. TikTok is a social media platform that enables users to create, share, and explore brief videos. TikTok’s user-friendly interface and creative features offer an engaging platform for learning. While learning technologies have traditionally supported knowledge transfer, research highlights their cognitive, behavioural, and affective benefits. Through a teaching intervention and qualitative feedback, students reported improved understanding of complex concepts. The TikTok assignment aligned with both inquiry-based learning (IBL) and decolonial pedagogies, encouraging independent inquiry, collaboration, and cultural relevance by valuing students’ voices and contexts. Though the study reflects a short-term, context-specific case and is not generalisable, it provides useful insights into students’ positive perceptions of using social media in science education. The findings indicate that integrating social media tools into the curriculum within the South African higher education landscape can introduce innovative learning methods. Future research should encompass a wider range of establishments and extend over longer durations to enhance its generalizability and address the current study’s limitations.