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•Effect of three different treatments to lignocellulose content of sugarcane biomass.•Direct-carbonization of sugarcane biomass to obtain anode for Na-ion battery.•Optimized carbon ...anode shows extremely low voltage plateau and outstanding stability.•In situ TEM study reveals small volume changes in the carbon after charge-discharge.
Development of low-cost anode for sodium-ion battery (NIB) has become the most desirable target in today’s energy demanding society. In this work, we present different treatments of sugarcane biomass to alter the lignocellulose compositions to obtain low-cost porous carbon as NIB’s anode. The optimized sugarcane biomass derived carbon presents the initial reversible capacity of 229 mAh g−1 and the reversible capacity of 189 mAh g−1 at 100 mA g−1 after 50 cycles. It is worth noting that the carbon also exhibits an extremely low voltage plateau with 74.2 % of discharge capacity originating from the voltages below 0.5 V. In addition, the sugarcane biomass derived carbon displays an ultra-stable capacity with almost no attenuation even after 2000 cycles. In consideration of the low voltage plateau, we also calculated the relative energy density (ER, combination of the capacity and voltage plateau), and a high ER of 500 Wh kg−1 in the first cycle and 416 Wh kg−1 after 50 cycles are obtained. In situ TEM analysis was conducted to investigate the structural stability of sugarcane biomass derived carbon. Small volumetric changes are observed at different charge-discharge states, indicating the structural stability of our sugarcane biomass derived carbon during sodiation-desodiation process, which is conducive to the stable cycling of Na-ions.
In large-scale, hydrogen production from water-splitting represents the most promising solution for a clean, recyclable, and low-cost energy source. The realization of viable technological solutions ...requires suitable efficient electrochemical catalysts with low overpotentials and long-term stability for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) based on cheap and nontoxic materials. Herein, we present a unique molecular approach to monodispersed, ultra-small, and superiorly active iron phosphide (FeP) electrocatalysts for bifunctional OER, HER, and overall water-splitting. They result from transformation of a molecular iron phosphide precursor, containing a Fe2P3 core with mixed-valence FeIIFeIII sites bridged by an asymmetric cyclo-P(2+1)3− ligand. The as-synthesized FeP nanoparticles act as long-lasting electrocatalysts for OER and HER with low overpotential and high current densities that render them one of the best-performing electrocatalysts hitherto known. The fabricated alkaline electrolyzer delivered low cell voltage with durability over weeks, representing an attractive catalyst for large-scale water-splitting technologies.
The hybrid Mg2+/Li+ battery (MLIB) is a very promising energy storage technology that combines the advantage of the Li and Mg electrochemistry. However, previous research has shown that the battery ...performance is limited due to the strong dependence on the Li content in the dual Mg2+/Li+ electrolyte. This limitation can be circumvented by significantly improving the diffusion kinetics of Mg2+ in the electrode, so that both Li+ and Mg2+ ions can be utilized as charge carriers. Herein, a free‐standing interlayer expanded MoS2/graphene composite (E‐MG) is demonstrated as a cathode for MLIB. The key advantage of this cathode is to enable the efficient intercalation of both Mg2+ and Li+. The E‐MG electrode displays a reversible capacity of ≈300 mA h g−1 at 20 mA g−1 in an MLIB cell, corresponding to a specific energy density up to ≈316.9 W h kg−1, which is comparable to that of the state‐of‐the‐art Li‐ion batteries (LIBs) and has no dendrite formation. The composite electrode is stable against cycling with a coulombic efficiency close to 100% at 500 mA g−1. This new electrode design represents a significant step forward for building a safe and high‐density electrochemical energy storage system.
Facile interlayer expansion in layered material with designed structure is applied in lithium–magnesium hybrid battery. With an improved magnesium ion diffusion kinetics and good electrochemical performance, it provides a step forward to the cost‐effective and high‐energy battery application.
Energy storage devices such as electrochemical supercapacitors, with high power and energy densities are required to address the colossal energy requirements against the backdrop of global warming ...and the looming energy crisis. Nanocarbon, particularly two-dimensional graphene and graphene-based conducting polymer composites are promising electrode materials for such energy storage devices. Owing to their environmental stability, the low cost of polymers with high electroactivity and pseudocapacitance, such composite hybrids are expected to have wide implications in next generation clean and efficient energy systems. In this feature article, an overview of current research and important advances over the past four years on the development of conducting polyaniline (PANI)-graphene based composite electrodes for electrochemical supercapacitors are highlighted. Particular emphasis is made on the design, fabrication and assembly of nanostructured electrode architectures comprising PANI and graphene along with metal oxides/hydroxides and carbon nanotubes. Comments on the challenges and perspectives towards rational design and synthesis of graphene-based conducting polymer composites for energy storage are discussed.
Energy storage devices such as electrochemical supercapacitors, with high power and energy densities are required to address the colossal energy requirements against the backdrop of global warming and the looming energy crisis.
In this paper, we report a flame deposition method to prepare carbon nanoparticles (CNPs) from coconut oil. The CNPs were further modified with a piranha solution to obtain surface-carboxylated ...carbon nanoparticles (c-CNPs). When used as an anode for sodium-ion batteries, the CNPs and c-CNPs respectively delivered discharge capacities of 277 and 278mAhg−1 in the second cycle at a current density of 100mAg−1. At the 20th cycle, the capacities of CNP and c-CNPs were 217 and 206mAhg−1 respectively. The results suggest that modification of the CNPs with the piranha solution improved neither the charge storage capacity nor the stability against cycling in a sodium-ion battery. When the CNP and c-CNP were used an anode in a lithium-ion battery, 2nd-cycle discharge capacities of 741 and 742mAhg−1 respectively at a current density of 100mAg−1 were obtained. After 20 cycles the capacities of CNP and c-CNP became 464 and 577mAhg−1 respectively, showing the cycling stability of the CNPs was improved after modification. The excellent cycling performance, high capacity and good rate capability make the present material as highly promising anodes for both sodium-ion and lithium-ion batteries.
Carbon nanoparticles derived from biomass and their electrochemical performance as anode in both sodium-ion and lithium-ion batteries.
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•Carbon nanoparticles (CNPs) were prepared from biomass.•CNPs work as a robust anode material with high discharge capacities for NIBs and LIBs.•CNPs exhibited superior rate and cycling performance for both LIBs and NIBs.
Porous, biodegradable and biocompatible chitosan, chitosan with natural hydroxyapatite derived from
Thunnus Obesus bone (chitosan/HAp) and chitosan grafted with functionalized multiwalled carbon ...nanotube in addition to HAp (
f-MWCNT-
g-chitosan/HAp) scaffolds were prepared for the first time via freeze-drying method and physiochemically characterized as bone graft substitutes. The cross-linkages in the novel
f-MWCNT-
g-chitosan/HAp scaffold were observed by FT-IR spectroscopy. The water uptake, retention ability and degradation of composite scaffolds decreased whereas thermal stability increased with an addition of HAp and
f-MWCNT. Uniform dispersion of HAp and
f-MWCNT in chitosan matrix with interconnected porosity of 70–200
μm (chitosan/HAp) and 46–200
μm (
f-MWCNT-
g-chitosan/HAp) was observed by X-ray diffraction, scanning electron microscopy and optical microscopy. Cell proliferation in composite scaffolds was twice than in pure chitosan when checked
in vitro using MG-63 cell line. These observations suggest that the novel chitosan/HAp and
f-MWCNT-
g-chitosan/HAp composite scaffolds are promising biomaterials for bone tissue engineering.
The overarching demand of modern electronics and electrification of transportation has tremendously increased usage of rechargeable lithium‐ion batteries (LIBs). As a result, massive amounts of solid ...waste are generated from the end‐of‐life LIBs and expected to increase by two‐ to threefolds in the near future. Without proper recycling strategies and infrastructure, the immediate threat of environmental pollution and wastage of resources is clear. One way to circumvent these challenges is to recycle the spent LIBs and recover the components and materials, especially heavy metals for future repurposing applications. This review highlights the recent discoveries on the use of deep eutectic solvents (DESs) as an economical and environmentally friendly medium for metal recovery from spent LIBs. Herein, how the different hydrogen donors and acceptors affect the overall performance of DES in terms of leaching efficiency, time, temperature, and metal recovery rates are outlined. Very importantly, the mechanism of metal leaching from the metal oxides using DES is discussed. Finally, some potential strategies and opportunities for further development of novel DES for metal‐recovery from not only spent LIBs but also other industries such as, mining, oil, and agriculture are outlined.
Deep eutectic solvents (DESs) are a new class of green solvents, which brings unique characteristics such as low cost, non‐toxic, biodegradable, and easy to synthesize. They have been recently explored as promising leaching agents to recover metals from spent batteries. The present review highlights recent strategies to design and develop novel DES and their potential for effective battery recycling.
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•Tailoring the crystal facet of electrocatalyst for syngas production.•HFGDEs provide sufficient CO2 supply and improved triple-phase interfaces.•Syngas selectivity over 90 % and ...achieved a production rate of 1328.6 µmol/h∙cm2.•This strategy can be versatile by loading other nanostructured electrocatalysts.
Electrochemical reduction of CO2 (CO2RR) in aqueous electrolytes not only relies on advanced gas diffusion electrodes (GDEs) to improve CO2 mass transportation but also efficient electrocatalysts to produce specific products. Herein, to produce syngas (CO and H2 mixture), a facet-orientated zinc nanosheet catalyst was electrodeposited on the Cu hollow fiber GDE via a controllable facile surfactant-assisted method. The introduction of cationic surfactant cetyl trimethyl ammonium bromide (CTAB) could manipulate the nucleation and crystal growth of zinc ions around the GDE during the electrodeposition process, leading to controlled changes in the surface free energy and tuned zinc crystal growth orientation. Consequently, the ZncNS-HF with the largest ratio of Zn (101)/Zn (002), resulted in a high current density of 73.3 mA/cm2 and a high syngas production rate of 1328.6 µmol/h∙cm2 at applied potential −1.3 V (vs. RHE). This comes from the hierarchical structure of HFGDE, which provides sufficient CO2 reaching the catalyst/electrolyte interface, and the well-connected zinc nanosheets contribute to a significant number of active sites for CO2RR. This is the first time to configure flow-through or gas-penetrated HFGDEs with zinc crystal facets controlled nanosheet catalysts for syngas production. This research demonstrates the high potential of nanoengineering catalysts for HFGDEs to achieve high production rates of syngas.
Pseudocapacitance, which is the storage of charge based on continuous and fast reversible redox reactions at the surface of electrode materials, is commonly observed for electrodes in lithium ion ...batteries, especially for transition metal oxide anodes. In this report, bare Fe2O3 of granular morphology (∼30 nm in diameter) with high purity and decent crystallinity as well as recommendable electrochemical performances is fabricated hydrothermally and employed as the subject to clarify pseudocapacitive behavior in transition metal oxide anodes. Electrochemical technologies such as galvanostatic charging/discharging, differential capacity analysis (dQ/dV) and the power law relationship (i = aνb), which can distinguish pseudocapacitive behaviors of an electrode reaction were employed to analyze the electrodes. Reversible capacities of ∼120 mA h g−1 (0.117 F cm−2) for Fe2O3 were found within particular electrochemical windows (2.3–3.0 V, 0.3–0.8 V for discharging and 2.2–3.0 V, 0.3–1.3 V for charging). A new direction of optimizing the capacities, rate and cycling performances for lithium ion batteries is pointed out with connections between the pseudocapacitive behavior and morphologies of surfaces as well as structures of the electrodes.
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