| 1. |
- Andersson, Rassmus, et al.
(författare)
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Micro versus Nano : Impact of Particle Size on the Flow Characteristics of Silicon Anode Slurries
- 2020
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Ingår i: ENERGY TECHNOLOGY. - : WILEY-V C H VERLAG GMBH. - 2194-4288 .- 2194-4296. ; 8:7
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Tidskriftsartikel (refereegranskat)abstract
- Silicon is interesting for use as a negative electrode material in Li-ion batteries due to its extremely high gravimetric capacity compared with today's state-of-the-art material, graphite. However, during cycling the Si particles suffer from large volume changes, leading to particle cracking, electrolyte decompositions, and electrode disintegration. Although utilizing nm-sized particles can mitigate some of these issues, it would instead be more cost-effective to incorporate mu m-sized silicon particles in the anode. Herein, it is shown that the size of the Si particles not only influences the electrode cycling properties but also has a decisive impact on the processing characteristics during electrode preparation. In water-based slurries and suspensions containing mu m-Si and nm-Si particles, the smaller particles consistently give higher viscosities and more pronounced viscoelastic properties, particularly at low shear rates. This difference is observed even when the Si particles are present as a minor component in blends with graphite. It is found that the viscosity follows the particle volume fraction divided by the particle radius, suggesting that it is dependent on the surface area concentration of the Si particles.
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| 2. |
- Aung, Soe Ko Ko, et al.
(författare)
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Enhanced Thermal Stability of Low-Temperature Processed Carbon-Based Perovskite Solar Cells by a Combined Antisolvent/Polymer Deposition Method
- 2022
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Ingår i: Energy Technology. - : Wiley-VCH Verlagsgesellschaft. - 2194-4288 .- 2194-4296. ; 10:8
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Tidskriftsartikel (refereegranskat)abstract
- Low-temperature processed carbon-based perovskite solar cells have received great attention due to low-cost, high stability, and simple preparation processes that can be employed in large-scale manufacturing. Carbon paste is deposited by techniques such as doctor blading or screen printing. However, solvents from this paste can damage the perovskite or underlying layers resulting in poor performance of solar cells. Furthermore, carbon is not an ideal hole-selective contact. To overcome these issues, the antisolvent treatment is combined with the deposition of a polymeric hole conductor. Specifically, poly(3-hexylthiophene) (P3HT), added into the chlorobenzene antisolvent, improves perovskite morphology and reduces interfacial carrier recombination. As a result, the power conversion efficiency (PCE) of solar cells with the device structure SnO2/MAPbI3/P3HT/carbon increases to 12.16% from 10.6% of pristine devices without P3HT, using pure antisolvent. For poly(triarylamine) hole conductor in the same method, PCE improves only slightly to 11.1%. After 260 h of thermal stress at 82 °C, the P3HT-additive devices improve PCE up to 13.2% in air and maintain 91% of their initial efficiency over 800 h.
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| 3. |
- Etman, Ahmed, et al.
(författare)
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On the Capacities of Freestanding Vanadium Pentoxide-Carbon Nanotube-Nanocellulose Paper Electrodes for Charge Storage Applications
- 2020
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Ingår i: ENERGY TECHNOLOGY. - : WILEY-V C H VERLAG GMBH. - 2194-4288 .- 2194-4296. ; 8:12
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Tidskriftsartikel (refereegranskat)abstract
- Herein, a one-step protocol for synthesizing freestanding 20 mu m thick cellulose paper electrodes composed of V2O5 . H2O nanosheets (VOx), carbon nanotubes (CNTs), and Cladophora cellulose (CC) is reported. In 1.0 m Na2SO4, the VOx-CNT-CC electrodes deliver capacities of about 200 and 50 C g(-1) at scan rates of 20 and 500 mV s(-1), respectively. The obtained capacities are compared with the theoretical capacities and are discussed based on the electrochemical reactions and the mass loadings of the electrodes. It is shown that the capacities are diffusion rate limited and, consequently, depend on the distribution and thickness of the V2O5 . H2O nanosheets, whereas the long-term cycling stabilities depend on vanadium species dissolving in the electrolyte. The electrodes feature high mass loadings (2 mg cm(-2)), good rate performances (25% capacity retention at 500 mV s(-1)), and capacity retentions of 85% after 8000 cycles. A symmetric VOx-CNT-CC energy storage device with a potential window of about 1 V exhibits a capacity of 40 C g(-1) at a scan rate of 2 mV s(-1).
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| 4. |
- Etman, Ahmed S., et al.
(författare)
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Acetonitrile-Based Electrolytes for Rechargeable Zinc Batteries
- 2020
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Ingår i: Energy technology. - : Wiley. - 2194-4288 .- 2194-4296. ; 8:9
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Tidskriftsartikel (refereegranskat)abstract
- Herein, Zn plating-stripping onto metallic Zn using a couple of acetonitrile (AN)-based electrolytes (0.5 mZn(TFSI)(2)/AN and 0.5 mZn(CF3SO3)(2)/AN) is studied. Both electrolytes show a reversible Zn plating/stripping over 1000 cycles at different applied current densities varying from 1.25 to 10 mA cm(-2). The overpotentials of Zn plating-stripping over 500 cycles at constant current of 1.25 and 10 mA cm(-2)are +/- 0.05 and +/- 0.2 V, respectively. X-ray photoelectron spectroscopy analysis reveals that no decomposition product is formed on the Zn surface. The anodic stability of four different current collectors of aluminum foil (Al), carbon-coated aluminum foil (C/Al), TiN-coated titanium foil (TiN/Ti), and multiwalled carbon nanotube paper (MWCNT-paper) is tested in both electrolytes. As a general trend, the current collectors have a higher anodic stability in Zn(TFSI)(2)/AN compared with Zn(CF3SO3)(2)/AN. The Al foil displays the highest anodic stability of approximate to 2.25 V versus Zn2+/Zn in Zn(TFSI)(2)/AN electrolyte. The TiN/Ti shows a comparable anodic stability with that of Al foil, but its anodic current density is higher than Al. The promising reversibility of the Zn plating/stripping combined with the anodic stability of Al and TiN/Ti current collectors paves the way for establishing highly reversible Zn-ion batteries.
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| 5. |
- Fenske, Markus, et al.
(författare)
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Improved Electrical Performance of Perovskite Photovoltaic Mini-Modules through Controlled PbI2 Formation Using Nanosecond Laser Pulses for P3 Patterning
- 2021
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Ingår i: Energy Technology. - : Wiley. - 2194-4288 .- 2194-4296. ; 9:4
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Tidskriftsartikel (refereegranskat)abstract
- The upscaling of perovskite solar cells to modules requires the patterning of the layer stack in individual cells that are monolithically interconnected in series. This interconnection scheme is composed of three lines, P1–P3, which are scribed using a pulsed laser beam. The P3 scribe is intended to isolate the back contact layer of neighboring cells, but is often affected by undesired effects such as back contact delamination, flaking, and poor electrical isolation. Herein, the influence of the laser pulse duration on the electrical and compositional properties of P3 scribe lines is investigated. The results show that both nanosecond and picosecond laser pulses are suitable for P3 patterning, with the nanosecond pulses leading to a higher open circuit voltage, a higher fill factor, and a higher power conversion efficiency. It is found that the longer pulse duration resultes in a larger amount of PbI2 formed within the P3 line and a thin Br-rich interfacial layer which both effectively passivate defects at the scribe line edges and block charge carrier in its vicinity. Thus, nanosecond laser pulses are preferable for P3 patterning as they promote the formation of beneficial chemical phases, resulting in an improved photovoltaic performance.
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| 6. |
- Johansson, Erik, et al.
(författare)
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Combining Quantum Dot and Perovskite Photovoltaic Cells for Efficient Photon to Electricity Conversion in Energy Storage Devices
- 2022
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Ingår i: Energy Technology. - : John Wiley & Sons. - 2194-4288 .- 2194-4296. ; 10:10
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Tidskriftsartikel (refereegranskat)abstract
- Renewable energy sources, such as wind and solar power, are increasingly important today to reduce emissions from fossil-based energy sources. However, the electricity from wind and solar power varies over time and depends on weather conditions and the time of the day. Therefore, to include a large fraction of electricity from these energy sources in the electricity grid, large-scale and low-cost energy storage is needed. Herein, it is investigated how a combination of quantum dot based photovoltaic cells and perovskite-based photovoltaic cells can be used to increase the energy conversion efficiency and increase the working range of energy storage devices based on conversion between heat, light, and electricity. The results show that these new types of photovoltaic materials have very promising properties for efficient utilization in energy storage devices, which have the potential for large-scale and low-cost energy storage.
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| 7. |
- Khossossi, Nabil, et al.
(författare)
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Strong Optical Excitation and High Thermoelectric Performance in 2D Holey-Phosphorene Monolayer
- 2022
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Ingår i: Energy Technology. - : John Wiley & Sons. - 2194-4288 .- 2194-4296. ; 10:10
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Tidskriftsartikel (refereegranskat)abstract
- Through density functional theory (DFT)-based computations, a systematic exploration of the newly predicted 2D phosphorene allotrope, namely holey-phosphorene (HP), is carried out. It is revealed that HP shows a semiconducting nature with an indirect bandgap of 0.83 eV upon Perdew-Burke-Ernzerhof (PBE) functional. Then, to survey the optical features, a (G(0)W(0))-based approach is employed to solve the Bethe-Salpeter equation to derive the intra-layer excitonic effects. It is derived via the absorption spectrum, that HP presents an excitonic binding strength of 1.47/1.96 eV along the x/y-direction with the first peak of the absorption at 0.92/0.43 eV for the x/y-direction. The thermoelectric properties are also explored in detail and reveal a very high thermal power value along with an enhanced figure of merit (ZT) of about 3.6. The 2D HP monolayer for thermoelectric performance has high thermoelectric conversion efficiency (TCE) and is estimated to be about 22%. All these outstanding findings may be attributed to the quantum confinement effect of the porous geometry of the 2D HP nanosheet, thereby confirming its relevance as a prospect for high-performance optoelectronic and thermoelectric engineering systems.
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| 8. |
- Liu, Lianlian, 1988-, et al.
(författare)
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Black Charcoal for Green and Scalable Wooden Electrodes for Supercapabatteries
- 2022
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Ingår i: Energy Technology. - : Wiley-VCH Verlag GMBH. - 2194-4288 .- 2194-4296. ; 10:3
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Tidskriftsartikel (refereegranskat)abstract
- A green, though black, sustainable and low-cost carbon material-charcoal produced from wood-is developed for electricity storage. Charcoal electrodes are fabricated by ball-milling charcoal and adding protein nanofibril binders. The charcoal electrode presents a capacitance of 360 F g(-1) and a conductivity of 0.2 S m(-1). A pair of redox peaks is observed in the cyclic voltammetry and assigned to originate from quinone groups. Compared with other wooden electrodes, these charcoal electrodes display better cycling stability with 88% capacity retention after 1000 cycles. Their discharge capacity is 2.5 times that of lignosulfonate/graphite hybrid electrodes.
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| 9. |
- Ma, Shengyu, et al.
(författare)
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Metal–Molybdenum Sulfide Nanosheet Arrays Prepared by Anion Exchange as Catalysts for Hydrogen Evolution
- 2020
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Ingår i: Energy Technology. - : Wiley-VCH Verlag. - 2194-4288 .- 2194-4296. ; 8:10
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Tidskriftsartikel (refereegranskat)abstract
- Metal–molybdenum sulfide (MMoSx)-based catalysts exhibit good performance over a wide pH range toward hydrogen evolution with relatively low overvoltage requirements. Therefore, they are considered as suitable alternatives to Pt as catalysts for hydrogen evolution reaction. Herein, self-supported amorphous CuMoSx and NiMoSx nanosheet arrays are prepared on copper foam (CF) and nickel foam (NF), respectively, through an anion-exchange strategy. CF and NF are first converted into CuTCNQ and NiTCNQ nanowire arrays (TCNQ = tetracyanoquinodimethane), which are then in situ reacted with (NH4)2MoS4 solution to generate amorphous CuMoSx/CF and NiMoSx/NF nanosheets, respectively, as efficient electrocatalysts for H2 generation. NiMoSx/NF exhibits a superior catalytic activity to CuMoSx/CF in 0.5 m H2SO4 solution, as CuMoSx/CF requires overpotentials (η) of 213 and 275 mV to obtain current densities of 10 and 50 mA cm−2, respectively, whereas NiMoSx/NF only requires η of 174 and 248 mV to receive the same current densities, respectively. Furthermore, these electrodes exhibit considerable long-term electrochemical durability. Herein, an effective and easy-to-operate strategy for the construction of self-supported metal–molybdenum sulfide nanosheet arrays films toward a highly efficient electrochemical hydrogen generation reaction is provided.
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| 10. |
- Mathies, Florian, et al.
(författare)
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Advances in Inkjet-Printed Metal Halide Perovskite Photovoltaic and Optoelectronic Devices
- 2020
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Ingår i: Energy Technology. - : Wiley. - 2194-4296 .- 2194-4288. ; 8:4
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Forskningsöversikt (refereegranskat)abstract
- Inkjet printing (IJP) has evolved over the past 30 years into a reliable, versatile, and cost-effective industrial production technology in many areas from graphics to printed electronic applications. Intensive research efforts have led to the successful development of functional electronic inks to realize printed circuit boards, sensors, lighting, actuators, energy storage, and power generation devices. Recently, a promising solution-processable material class has entered the stage: metal halide perovskites (MHPs). Within just 10 years of research, the efficiency of perovskite solar cells (PSCs) on a laboratory scale increased to over 25%. Despite the complex nature of MHPs, significant progress has also been made in controlling film formation in terms of ink development, substrate wetting behavior, and crystallization processes of inkjet-printed MHPs. This results in highly efficient inkjet-printed PSCs with a power conversion efficiency (PCE) of almost 21%, paving the way for cost-effective and highly efficient thin-film solar cell technology. In addition, the excellent optoelectronic properties of inkjet-printed MHPs achieve remarkable results in photodetectors, X-ray detectors, and illumination applications. Herein, a comprehensive overview of the state-of-the-art and recent advances in the production of inkjet-printed MHPs for highly efficient and innovative optoelectronic devices is provided.
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| 11. |
- Moldenhauer, Patrick, 1983, et al.
(författare)
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Oxygen-Carrier Development of Calcium Manganite–Based Materials with Perovskite Structure for Chemical-Looping Combustion of Methane
- 2020
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Ingår i: Energy Technology. - : Wiley. - 2194-4296 .- 2194-4288. ; 8:6
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Tidskriftsartikel (refereegranskat)abstract
- The present work is related to the upscaling of calcium manganite–based oxygen-carrier materials, which have a perovskite structure, both with respect to the use of inexpensive raw materials, i.e., instead of pure chemicals, and the upscaling of production to multitonne batches. Results are presented from the two different stages of material development, i.e., raw material selection and upscaling. The evaluation involves both operation in chemical-looping combustor units of 300 W and 10 kW, and material characterization. In the latter unit, the gas velocities in the riser and in the grid-jet zone of the gas distributor come close to gas velocities of industrial-scale units and, therefore, this unit is also used to assess particle lifetime. Results from the various chemical-looping combustion units and oxygen-carrier materials produced from various raw materials of both high and low purity show that very high degrees of fuel conversion can be reached while achieving very high oxygen-carrier lifetimes. The composition of the oxygen-carrier materials seems robust and flexible with respect to the precursors used in its manufacturing.
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| 12. |
- Surywanshi, Gajanan Dattarao, 1989, et al.
(författare)
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Energy, Exergy, Economic and Exergoeconomic Analyses of Chemical Looping Combustion Plant Using Waste Bark for District Heat and Power Generation with Negative Emissions
- 2024
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Ingår i: Energy Technology. - : John Wiley and Sons Inc. - 2194-4296 .- 2194-4288. ; 12:2
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Tidskriftsartikel (refereegranskat)abstract
- The greenhouse gas emissions from the boiler of pulp and paper industries can be minimized by adapting chemical looping combustion (CLC) technology. This work aims to analyze the energy, exergy, economic, and exergoeconomic performance of an industrial scale CLC plant for district heat and electricity generation using waste bark from the paper and pulp industry. The CLC plant with one natural ore and one industrial waste oxygen carrier (OC) is modeled using Aspen Plus. The performance of the CLC plant has been compared to Örtofta combined heat and power plant without CO2 capture and with post-combustion CO2 capture as the reference cases. Results showed that the CLC-based power plant is energetically, exegetically, and economically efficient compared to the reference cases. The circulating fluidized bed boiler unit contributes the highest exergy destruction (about 50–80%). Among the CO2 capture plants, the CLC plant with ilmenite has the lowest levelized cost of district heat (4.58 € GJ−1), and a payback period (9.69 years) followed by the CLC plant with LD slag (5.91 € GJ−1 and 11.84 years), and the plant with PCC (6.94 € GJ−1 and 13.58 years). The exergoeconomic analysis reveals that the CLC reactors have the highest cost reduction potential, followed by the steam turbine.
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| 13. |
- Wang, Xiaoxiao, et al.
(författare)
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Copper Selenide-Derived Copper Oxide Nanoplates as a Durable and Efficient Electrocatalyst for Oxygen Evolution Reaction
- 2020
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Ingår i: Energy Technology. - : Wiley. - 2194-4288 .- 2194-4296. ; 8:7
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Tidskriftsartikel (refereegranskat)abstract
- Earth-abundant transition metal-based nanomaterials play a signi?cant role in oxygen evolution reaction (OER). Among them, copper has attracted signi?cant attention due to its excellent electrocatalytic activity, low price, and abundance. Herein, a nanostructured copper oxide (CuO-A) is generated in situ from a cuprous selenide (Cu2Se) precursor under oxygen evolution reaction conditions. The as-prepared CuO-A/copper foam (CF) electrode delivers a current density of 10 mA cm(-2) at an overpotential of 297 mV with good stability for over 50 h in 1 m KOH solution, which is superior to most recently reported copper-based water oxidation catalysts. The high catalytic performance of CuO-A is mainly attributed to the improved surface area offered by the morphology reconstruction during the in situ transformation process. As a result, it paves a way to synthesize effective and stable transition metal oxide catalysts via the in situ conversion of transition metal chalcogenides for energy conversion and storage applications.
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| 14. |
- Wu, Zhixing, 1990-, et al.
(författare)
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Bifunctional Mesoporous MO x (M = Cr, Fe, Co, Ni, Ce) Oxygen Electrocatalysts for Platinum Group Metal-Free Oxygen Pumps
- 2022
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Ingår i: Energy Technology. - : Wiley-V C H Verlag GMBH. - 2194-4288 .- 2194-4296. ; 10:12
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Tidskriftsartikel (refereegranskat)abstract
- Bifunctional electrocatalysts with both accelerated oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) enable high-power density electricity storage and decentralized extraction of pure oxygen from air for usage in health care. Herein, a hydrothermal synthesis employing the anionic surfactant sodium dodecyl sulfate as structure-directing agent is developed to fabricate a family of crystalline mesoporous metal oxides (meso-MO X , M = Cr, Fe, Co, Ni, Ce). The pore size and specific surface area depend on the metal used and they range from 3 to 6 nm and 60 to 200 m(2) g(-1), respectively. NiO and Co3O4 show a higher catalytic efficiency in alkaline media in comparison with the other oxides studied, and their activities are comparable with the values reported for platinum group metal (PGM)-based electrocatalysts. This stems from lower voltage losses and by the presence of specific hydroxide adsorbates on the surface. Both ORR and OER driven on Co3O4 show the unified rate-determining chemical step (|OO-|(center dot) (ads) + H2O <-> |OOH|(center dot) (ads) + OH-, where | X | ads are the species adsorbed on active sites). The bifunctional ORR/OER electrocatalysis obtained on mesoporous NiO is utilized for the first symmetrical PGM-free oxygen pump fed by air and water only.
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| 15. |
- Xue, Xiaoyin, et al.
(författare)
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Enhanced Storage and Interface Structure Stability of NCM811 Cathodes for Lithium-Ion Batteries by Hydrophobic Fluoroalkylsilanes Modification
- 2022
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Ingår i: ENERGY TECHNOLOGY. - : Wiley-VCH Verlagsgesellschaft. - 2194-4288 .- 2194-4296. ; 10:4
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Tidskriftsartikel (refereegranskat)abstract
- The nickel-rich ternary-layered oxide LiNixCoyMn(1-x-y)O2 (NCM) cathode exhibits high reversible capacity and low cost; however, severe capacity fade and aggravated air degradation prohibit its widespread commercialization. Herein, the hydrophobic fluoroalkylsilane-modified NCM811 cathode materials are reported. To better understand the effects of electrochemical properties of lithium-ion batteries, a variety of characterization techniques and electrochemical methods are utilized to study the surface chemistry at the cathode/electrolyte interphase. The hydrophobic fluoroalkylsilanes-grafted NCM811 cathode materials suppress the formation of residual lithium even after 30 days in humid air. The fluoroalkylsilanes layer can also provide chemical stabilization to the NCM811 cathode materials by anchoring transition metals (TM) and suppressing TM dissolution during long immersion times in electrolytes. Moreover, the degree of improvement depends on the structure of the fluoroalkylsilanes, such as the number of F groups and the length of carbon chains. As a result, FAS17-modified NCM811 cathode materials after 30-day humid air exposure (humidity 70%) exhibit the greatest overall capacity retention of 74.2% after 200 charge/discharge cycles.
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| 16. |
- Xue, Xiaoyin, et al.
(författare)
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PEDOT:PSS @Molecular Sieve as Dual-Functional Additive to Enhance Electrochemical Performance and Stability of Ni-Rich NMC Lithium-Ion Batteries
- 2020
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Ingår i: Energy Technology. - : Wiley. - 2194-4288 .- 2194-4296. ; 8:10
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Tidskriftsartikel (refereegranskat)abstract
- Molecular sieves (MSs) coated with conductive polymer (PEDOT:PSS) are used as water scavengers to modify the nickel‐rich LiNi1–x–yCoxMnyO2 (NMC)‐layered cathode. This strategy proactively captures residual water in the battery system without affecting the transport performance of electrons and Li+ ions. The moisture content and nuclear magnetic resonance (NMR) tests show that MSs after coating still maintain good water absorption characteristics and inhibit the decomposition of the electrolyte. The conductivity of the PEDOT:PSS@MS‐NMC electrode is 1.08 × 10−4 S cm−1, which is improved by 63.9%, compared with the MS‐NMC electrode. Through X‐ray photoelectron spectroscopy, transmission electron microscopy, and scanning electron microscopy measurements, it is also shown that the surface structure stability and particle integrity for PEDOT:PSS@MS‐NMC electrode is well retained. After 500 cycles, the capacity retention of the composite cathode is 71.3%, which is higher than that of the NMC (38.3%) and MS‐NMC cathode (62.4%). This is a novel and effective strategy to suppress side reactions at the electrode interface and improve electrode stability, capacity retention, and cycle performance of the Ni‐rich NMC cathode.
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| 17. |
- Yin, Litao, et al.
(författare)
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An Integrated Flow–Electric–Thermal Model for a Cylindrical Li-Ion Battery Module with a Direct Liquid Cooling Strategy
- 2022
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Ingår i: Energy Technology. - : Wiley. - 2194-4296 .- 2194-4288. ; 10:8
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Tidskriftsartikel (refereegranskat)abstract
- An integrated model is constructed for a Li-ion battery module composed of cylindrical cells by coupling individual first-order equivalent circuit models (ECMs) with a 3D heat transfer model, also considering the fluid flow dynamics of the applied cooling liquid, and bench-marked against experimental data. This model simulates a representative unit of the battery module with direct liquid cooling in a parallel configuration. Instead of assigning specific values to the featured parameters involved in the ECMs, they are here defined as 4D arrays. This makes it possible to simultaneously consider the effect of the state of charge, current rate, and temperature on the battery dynamics, making the model more adaptive, versatile, and connectable to the battery cell electrochemistry. According to the simulation results, the model employing state-dependent battery properties fits better with the experimental cooling results. Additionally, the temperature uniformity of the module with a parallel cooling configuration is improved compared to a serial configuration. However, the increase of the absolute core temperature cannot be directly controlled by the surface cooling due to the slow heat transport rate across the battery material. The simulations also provide directions for the modification of module design, to the potential benefit of battery pack developers.
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| 18. |
- Zhang, Wenjing, et al.
(författare)
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Highly Structured Nanofiber Zeolite Materials for Biogas Upgrading
- 2020
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Ingår i: Energy Technology. - : John Wiley & Sons. - 2194-4296 .- 2194-4288. ; 8:1
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Tidskriftsartikel (refereegranskat)abstract
- Hierarchical zeolite composite nanofibers are designed using an electrospinning technique with post‐carbonization processing to form mechanically strong pellets for biogas upgrading. A ZSM‐5 nanopowder (zeolite) and a polyvinylpyrrolidone (PVP) polymer are electrospun to form ZSM/PVP composite nanofibers, which are transformed into a ZSM and carbon composite nanofiber (ZSM/C) by a two‐step heat treatment. The ZSM/C nanofibers show a 30.4% increase in Brunauer–Emmett–Teller (BET) surface area compared with the non‐structured ZSM‐5 nanopowder. Using ideal adsorbed solution theory, CO2‐over‐CH4 selectivity of 20 and CO2 uptake of 2.15 mmolg−1 at 293 K at 1 bar for ZSM/C nanofibers are obtained. For the efficient use of adsorbents in pressure swing adsorption operation, the nanofibers are structured into ZSM/C pellets that offer a maximum tensile strength of 6.46 MPa to withstand pressure swings. In the breakthrough tests, the CO2 uptake of the pellets reach 3.18 mmolg−1 at 293 K at 4 bar after 5 breakthrough adsorption–desorption cycles, with a much higher mass transfer coefficient of 1.24 ms−1 and CO2 uptake rate of 2.4 mg of CO2 g−1s−1, as compared with other structured zeolite adsorbents.
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| 19. |
- Zhao, Yi, et al.
(författare)
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Improved Proton Adsorption and Charge Separation on Cadmium Sulfides for Photocatalytic Hydrogen Production
- 2022
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Ingår i: Energy Technology. - : John Wiley & Sons. - 2194-4288 .- 2194-4296. ; 10:12
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Tidskriftsartikel (refereegranskat)abstract
- Cadmium sulfide has attracted wide attention in photocatalytic hydrogen production, due to its appropriate bandgap and band positions. However, high-rate photogenerated electron-hole recombination and few active sites on CdS lead to its low photocatalytic activity. Herein, a PANI/NCPP/CdS (PANI/NiCoP/NiCoPi/CdS) hybrid as a noble metal-free visible light-driven photocatalyst is reported, with metal phosphides, metal phosphates, and polyaniline (PANI) as reduction and oxidation cocatalysts, respectively. This hybrid not only facilitates the charge separation and transfer owing to the formation of heterojunction, but also improves the local concentration of H+ on the surface of catalysts due to the formation of the protonated amine groups on PANI, bene?cial to hydrogen evolution reaction. As a result, the as-prepared photocatalyst could show a high hydrogen evolution rate of 170.3 mmol g(-1) h(-1) and an apparent quantum efficiency of 41.37% at 420 nm, representing one of the best performances of all-CdS-based photocatalysts.
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