Electrochemical Study of Biotin-Modified Self-Assembled Monolayers: Recommendations for Robust Preparation

The development of the underpinning methodology for the production of robust, well-formed, and densely packed biotin-HPDP functionalised gold surfaces, the crucial first step in immobilising bimolecules on surfaces, is described. Self-assembled monolayers (SAMs) with biotin end-groups were prepared on polycrystalline gold surfaces according to a published method. The layers formed were studied using cyclic voltammetry to determine the composition of the layer and its quality. Crystal impedance spectroscopy was also applied as a complimentary indicator of the composition of the layer.For the first time, the effect of assembly time on the properties of the layer was studied along with the composition of the layer and the ability of the precursor molecule to self-assemble by oxidative addition

Insights into in-situ catalytic degradation of plastic wastes over zeolite-based catalyst from perspective of three-dimensional pore structure evolution

Acknowledgements The authors are grateful for financial supports provided by the Royal Society of Chemistry Enablement Grant (E21-5819318767) and Royal Society of Chemistry Mobility Grant (M19-2899), National Natural Science Foundation of China (No. 51906110), the Natural Science Foundation of Jiangsu province, China (No. BK20190465). The authors gratefully acknowledge financial support from China Scholarship Council.Peer reviewedPublisher PD

X-ray tomography-assisted study of a phase inversion process in ceramic hollow fiber systems – Towards practical structural design

Phase inversion-assisted extrusion processes provide a feasible approach for the development of micro-structured ceramic hollow fibers. The mass transport of the hollow fiber, which is closely correlated to the pore structure, is especially important in the application of fuel cell electrodes and membrane reactors. Whilst the relationship between the pore microstructure and the fabrication factors has been the subject of significant investigations, there remains much disagreement in the literature. Recent development in X-ray computed tomography (CT) has enabled new insight into 3D microstructures, which could help to realize practical morphology design and optimization. In this study, a series of alumina hollow fibers have been prepared with varied polymer binder (polyethersulfone, PESf) concentration and new polymer-based internal coagulant (aqueous solution of polyvinyl alcohol, PVA). For the first time, the micro-channels were characterized in 3D using X-ray CT to determine micro-channel densities and diameters in the radial direction, as well as the 2D measurement of the pore size in the sponge-like layer. Water permeation tests were then conducted to correlate the micro-structure of the hollow fiber to the permeability. Results show that the diameter of the micro-channels decreases as the concentration of polymer binder increases, but the pore size in the spongy-like layer becomes larger. When the polymer binder concentration is increased from 16 wt% to 30 wt%, the maximum micro-channel diameter is almost halved (from 29 to 15 µm), and the radial length is 60% longer, whereas the mean flow pore size in the sponge-like layer is increased from approximately 288 to 422 nm. Larger pore size in the spongy-like layer of the high PVA concentration sample contributes to a better permeability (pure water flux almost doubled), but the dimension of the micro-channels is less important. This study provides a new approach to optimize fabrication of hollow fibers for various applications

High power Nb-doped LiFePO₄ Li-ion battery cathodes; pilot-scale synthesis and electrochemical properties

AbstractHigh power, phase-pure Nb-doped LiFePO4 (LFP) nanoparticles are synthesised using a pilot-scale continuous hydrothermal flow synthesis process (production rate of 6 kg per day) in the range 0.01–2.00 at% Nb with respect to total transition metal content. EDS analysis suggests that Nb is homogeneously distributed throughout the structure. The addition of fructose as a reagent in the hydrothermal flow process, followed by a post synthesis heat-treatment, affords a continuous graphitic carbon coating on the particle surfaces. Electrochemical testing reveals that cycling performance improves with increasing dopant concentration, up to a maximum of 1.0 at% Nb, for which point a specific capacity of 110 mAh g−1 is obtained at 10 C (6 min for the charge or discharge). This is an excellent result for a high power cathode LFP based material, particularly when considering the synthesis was performed on a large pilot-scale apparatus

In-Situ Li-Ion Pouch Cell Diagnostics Utilising Plasmonic Based Optical Fibre Sensors

As the drive to improve the cost, performance characteristics and safety of lithium-ion batteries increases with adoption, one area where significant value could be added is that of battery diagnostics. This paper documents an investigation into the use of plasmonic-based optical fibre sensors, inserted internally into 1.4 Ah lithium-ion pouch cells, as a real time and in-situ diagnostic technique. The successful implementation of the fibres inside pouch cells is detailed and promising correlation with battery state is reported, while having negligible impact on cell performance in terms of capacity and columbic efficiency. The testing carried out includes standard cycling and galvanostatic intermittent titration technique (GITT) tests, and the use of a reference electrode to correlate with the anode and cathode readings separately. Further observations are made around the sensor and analyte interaction mechanisms, robustness of sensors and suggested further developments. These finding show that a plasmonic-based optical fibre sensor may have potential as an opto-electrochemical diagnostic technique for lithium-ion batteries, offering an unprecedented view into internal cell phenomena

TiO2/MoO2 nanocomposite as anode materials for high power Li-ion batteries with exceptional capacity

Nanoparticles of molybdenum(IV) oxide (MoO 2 ) and a TiO 2 /MoO 2 nanocomposite were synthesised via a continuous hydrothermal synthesis process. Both powders were analysed using XRD, XPS, TEM, and BET and evaluated as active materials in anodes for Li-ion half-cells. Cyclic voltammetry and galvanostatic charge/discharge measurements were carried out in the potential window of 0.1 to 3.0 V vs. Li/Li+. Specific capacities of ca. 350 mAh g -1 were obtained for both materials at low specific currents (0.1 A g -1 ); TiO 2 /MoO 2 composite electrodes showed superior rate behaviour & stability under cycling (compared to MoO 2 ), with stable specific capacities of ca. 265 mAh g -1 at a specific current of 0.5 A g -1 and ca. 150 mAh g -1 after 350 cycles at a specific current of 2.5 A g -1 . The improved performance of the composite material, compared to MoO 2 , was attributed to a smaller particle size, improved stability to volume changes (during cycling), and lower charge transfer resistance during cycling. Li-ion hybrid electrochemical capacitors using TiO 2 /MoO 2 composite anodes and activated carbon (AC) cathodes were evaluated and showed excellent performance with an energy density of 44 Wh kg -1 at a power density of 600 W kg -1

Study of H2S Removal Capability from Simulated Biogas by Using Waste-Derived Adsorbent Materials

Funding: This work was part of the research activities carried out in the framework of the “European Biofuels Research Infrastructure for Sharing Knowledge 2 (BRISK2)” project under grant agreement 731101 (https://brisk2.eu/) and the European Commission is acknowledged for co-funding the work.Peer reviewedPublisher PD

Multi-scale Designed CoxMn3–xO4 Spinels : Smart Pre-Catalysts towards High-Efficiency Pyrolysis-Catalysis Recycling of Waste Plastics

Acknowledgements M. W. and A. W. highly acknowledge the funding by the German Federal Ministry of Education and Research (BMBF) within the NexPlas project (project number: 03SF0618B). Y. S. Z is grateful for financial supports provided by the Royal Society of Chemistry Enablement Grant (E21-5819318767) and Royal Society of Chemistry Mobility Grant (M19-2899).Peer reviewedPostprin

Palladium alloys used as electrocatalysts for the oxygen reduction reaction

Palladium-based alloy materials as cathodes for the reduction of oxygen are regarded as potential substitutes for platinum-based catalysts in fuel cells. In this work, we present the scientometric analysis and critically review the use of Pd alloys for the oxygen reduction reaction (ORR). Through scientometric analysis, publication information, research fronts and hotspots are identified. For the critical review, reaction mechanisms in different media are discussed, with the aid of volcano plots to show the general principles for catalyst modifications to maximise the ORR. Influencing factors, including alloying, structure, strain and ligand, particle size, crystal facet and dealloying are considered with a view to informing the theoretical feasibility to enhance ORR activity. In addition, Pd-based alloys synthesized by different methods are presented and compared in terms of ORR activities. Future research directions are discussed and possible approaches to the mass production for industrialization are also proposed

Roadmap for a sustainable circular economy in lithium-ion and future battery technologies

The market dynamics, and their impact on a future circular economy for lithium-ion batteries (LIB), are presented in this roadmap, with safety as an integral consideration throughout the life cycle. At the point of end-of-life (EOL), there is a range of potential options—remanufacturing, reuse and recycling. Diagnostics play a significant role in evaluating the state-of-health and condition of batteries, and improvements to diagnostic techniques are evaluated. At present, manual disassembly dominates EOL disposal, however, given the volumes of future batteries that are to be anticipated, automated approaches to the dismantling of EOL battery packs will be key. The first stage in recycling after the removal of the cells is the initial cell-breaking or opening step. Approaches to this are reviewed, contrasting shredding and cell disassembly as two alternative approaches. Design for recycling is one approach that could assist in easier disassembly of cells, and new approaches to cell design that could enable the circular economy of LIBs are reviewed. After disassembly, subsequent separation of the black mass is performed before further concentration of components. There are a plethora of alternative approaches for recovering materials; this roadmap sets out the future directions for a range of approaches including pyrometallurgy, hydrometallurgy, short-loop, direct, and the biological recovery of LIB materials. Furthermore, anode, lithium, electrolyte, binder and plastics recovery are considered in order to maximise the proportion of materials recovered, minimise waste and point the way towards zero-waste recycling. The life-cycle implications of a circular economy are discussed considering the overall system of LIB recycling, and also directly investigating the different recycling methods. The legal and regulatory perspectives are also considered. Finally, with a view to the future, approaches for next-generation battery chemistries and recycling are evaluated, identifying gaps for research. This review takes the form of a series of short reviews, with each section written independently by a diverse international authorship of experts on the topic. Collectively, these reviews form a comprehensive picture of the current state of the art in LIB recycling, and how these technologies are expected to develop in the future