Low-Temperature Synthesis of Titanium Oxynitride Nanoparticles

The synthesis of transition metal oxynitrides is complicated by extreme reaction conditions such as high temperatures and/or high pressures. Here, we show an unprecedented solution-based synthesis of narrowly dispersed titanium oxynitride nanoparticles of cubic shape and average size of 65 nm. Their synthesis is performed by using titanium tetrafluoride and lithium nitride as precursors alongside trioctylphosphine oxide (TOPO) and cetrimonium bromide (CTAB) as stabilizers at temperatures as low as 250 °C. The obtained nanoparticles are characterized in terms of their shape and optical properties, as well as their crystalline rock-salt structure, as confirmed by XRD and HRTEM analysis. We also determine the composition and nitrogen content of the synthesized particles using XPS and EELS. Finally, we investigate the applicability of our titanium oxynitride nanoparticles by compounding them into carbon fiber electrodes to showcase their applicability in energy storage devices. Electrodes with titanium oxynitride nanoparticles exhibit increased capacity compared to the pure carbon material.

Download Full-text

Systematic Design of Polypyrrole/Carbon Fiber Electrodes for Efficient Flexible Fiber-Type Solid-State Supercapacitors

Nanomaterials ◽

10.3390/nano10020248 ◽

2020 ◽

Vol 10 (2) ◽

pp. 248 ◽

Cited By ~ 6

Author(s):

Yu-Shun Sung ◽

Lu-Yin Lin

Keyword(s):

Energy Storage ◽

Carbon Fiber ◽

Fiber Type ◽

Coulombic Efficiency ◽

Discharge Process ◽

Energy Storage Devices ◽

Storage Devices ◽

Flexible Fiber ◽

Carbon Fiber Electrodes ◽

Soft Electronics

Fiber-type supercapacitors (FSC) have attracted much attention as efficient energy storage devices for soft electronics. This study proposes the synthesis of polypyrrole (PPy) on carbon fiber (CF) using electropolymerization as the energy storage electrode for FSC. Effects of the electrolyte, applied current, and time of electropolymerization for synthesizing PPy on CF are investigated. The configuration of the electrochemical system is also studied to better understand the electropolymerization of PPy. The highest specific capacitance (CM) of 308.2 F/g are obtained for the PPy electrode prepared using 0.5 M pyrrole and 0.3 M NaClO4 as the electrolyte at 40 mA for 20 min. The FSC assembled with PPy electrodes and the polyvinyl alcohol/H3PO4 gel electrolyte shows a CM value of 30 F/g and the energy density of 5.87 Wh/kg at the power density of 60.0 W/kg. Excellent cycling stability with CM retention of 70% and Coulombic efficiency higher than 98% in 3000 times charge/discharge process, and the good bending capability with CM retention of 153% and 148%, respectively, under the bending angle of 180° and the bending times of 600 are achieved. This work gives deeper understanding of electropolymerization and provides recipes for fabricating an efficient PPy electrode for soft energy storage devices.

Download Full-text

Enzymatic Synthesis, Characterization and Biocompatibility Studies of Cellulose Nanoparticles from Cotton Fibers

Advances in Nanoscience and Nanotechnology ◽

10.33140/02/01/00009 ◽

2018 ◽

Vol 2 (1) ◽

Keyword(s):

Lung Epithelial Cells ◽

Cotton Fibers ◽

Energy Storage Devices ◽

Storage Devices ◽

Cellulose Nanoparticles ◽

Viability Assay ◽

Wide Range ◽

New Energy ◽

Green Catalysis ◽

Average Size

Interest in cellulose nanoparticles has been increasing exponentially in the past few decades due to its unique characteristics such as reinforcement properties, high tensile strength, and excellent thermal and electrical properties. Cellulose nanoparticles were produced by an enzymatic method including hydrolysis of cotton fibers by cellulase enzyme and sonication process. Further, cellulose nanoparticles were characterized to determine the morphology and purity of the material. Characterization of cellulose nanoparticles was performed by Scanning Electron Microscope (SEM) with Energy Dispersive X-Ray Spectroscopy (EDX) and Fourier Transform Infrared Spectroscopy (FT-IR). Biocompatibility studies of cellulose nanoparticles were carried out by MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) assay and Live/Dead viability assay. Using SEM, the average size of cellulose nanoparticles was found to be around 100-125nm and the particles were spherical in shape. FTIR spectrum showed the formation of cellulose nanoparticles from cotton fibers without any presence of impurities. MTT assay and Live/Dead viability assay showed no significant induction of cell death even at higher concentrations (100 μg) upon exposure to Rat Lung Epithelial cells. The results revealed that the synthesized cellulose nanoparticles could be used in wide range of emerging applications in the development of new energy storage devices, enzyme immobilization, antimicrobial and medical materials, green catalysis, bio-sensing and controlled drug delivery.

Download Full-text

Flexible and wearable fiber shaped high voltage supercapacitors based on copper hexacyanoferrate and porous carbon coated carbon fiber electrodes

Journal of Materials Chemistry A ◽

10.1039/c6ta00093b ◽

2016 ◽

Vol 4 (13) ◽

pp. 4934-4940 ◽

Cited By ~ 35

Author(s):

S. T. Senthilkumar ◽

Junsoo Kim ◽

Yu Wang ◽

Haitao Huang ◽

Youngsik Kim

Keyword(s):

Energy Storage ◽

Carbon Fiber ◽

High Voltage ◽

Light Weight ◽

Energy Storage Devices ◽

Copper Hexacyanoferrate ◽

Storage Devices ◽

Carbon Fiber Electrodes ◽

Carbon Coated ◽

Coated Carbon

Fiber supercapacitors have been considered as one of the promising candidates for light weight, flexible and wearable energy storage devices.

Download Full-text

An aqueous hybrid electrolyte for low-temperature zinc-based energy storage devices

Energy & Environmental Science ◽

10.1039/d0ee01538e ◽

2020 ◽

Vol 13 (10) ◽

pp. 3527-3535 ◽

Cited By ~ 1

Author(s):

Nana Chang ◽

Tianyu Li ◽

Rui Li ◽

Shengnan Wang ◽

Yanbin Yin ◽

...

Keyword(s):

Energy Storage ◽

Low Temperature ◽

Energy Storage Devices ◽

Storage Devices

A frigostable aqueous hybrid electrolyte enabled by the solvation interaction of Zn2+–EG is proposed for low-temperature zinc-based energy storage devices.

Download Full-text

NMR studies of alkali intercalted carbon nanotubes

MRS Proceedings ◽

10.1557/proc-772-m3.4 ◽

2003 ◽

Vol 772 ◽

Cited By ~ 1

Author(s):

M. Schmid ◽

C. Goze-Bac ◽

M. Mehring ◽

S. Roth ◽

P. Bernier

Keyword(s):

Carbon Nanotubes ◽

Lattice Relaxation ◽

Spin Lattice Relaxation ◽

Energy Storage Devices ◽

Nmr Studies ◽

Storage Devices ◽

Spin Lattice ◽

Relaxation Measurements ◽

Resonance Spin ◽

Walled Carbon Nanotubes

AbstractLithium intercalted carbon nanotubes have attracted considerable interest as perspective components for energy storage devices. We performed 13C Nuclear Magnetic Resonance spin lattice relaxation measurements in a temperature range from 4 K up to 300 on alkali intercalated Single Walled Carbon Nanotubes in order to investigate the modifications of the electronic properties. The density of states at the Fermi level were determined for pristine, lithium and cesium intercalated carbon nanotubes and are discussed in terms of intercalation and charge transfer effects.

Download Full-text

How Certain Are the Reported Ionic Conductivities of Thiophosphate-Based Solid Electrolytes? an Interlaboratory Study

10.26434/chemrxiv.11316497.v2 ◽

2020 ◽

Author(s):

Saneyuki Ohno ◽

Tim Bernges ◽

Johannes Buchheim ◽

Marc Duchardt ◽

Anna-Katharina Hatz ◽

...

Keyword(s):

Standard Deviation ◽

Ionic Conductivity ◽

Relative Standard Deviation ◽

Solid Electrolytes ◽

Ionic Conductivities ◽

Ionic Conductors ◽

Energy Storage Devices ◽

Activation Barriers ◽

Storage Devices ◽

Relative Standard

Owing to highly conductive solid ionic conductors, all-solid-state batteries attract significant attention as promising next-generation energy storage devices. A lot of research is invested in the search and optimization of solid electrolytes with higher ionic conductivity. However, a systematic study of an interlaboratory reproducibility of measured ionic conductivities and activation energies is missing, making the comparison of absolute values in literature challenging. In this study, we perform an uncertainty evaluation via a Round Robin approach using different Li-argyrodites exhibiting orders of magnitude different ionic conductivities as reference materials. Identical samples are distributed to different research laboratories and the conductivities and activation barriers are measured by impedance spectroscopy. The results show large ranges of up to 4.5 mScm-1 in the measured total ionic conductivity (1.3 – 5.8 mScm-1 for the highest conducting sample, relative standard deviation 35 – 50% across all samples) and up to 128 meV for the activation barriers (198 – 326 meV, relative standard deviation 5 – 15%, across all samples), presenting the necessity of a more rigorous methodology including further collaborations within the community and multiplicate measurements.

Download Full-text

Ultrathin Carbon Nanosheets for Highly-efficient Capacitive K-ion and Zn-ion Storage

10.26434/chemrxiv.12413411.v2 ◽

2020 ◽

Author(s):

Yamin Zhang ◽

Zhongpu Wang ◽

Deping Li ◽

Qing Sun ◽

Kangrong Lai ◽

...

Keyword(s):

Energy Storage ◽

Porous Carbon ◽

Metal Ion ◽

Rate Capability ◽

Energy Storage Devices ◽

Capacity Retention ◽

Carbon Nanosheets ◽

Storage Devices ◽

High Efficient ◽

Ion Storage

Porous carbon has attracted extensive attentions as the electrode material for various energy storage devices considering its advantages like high theoretical capacitance/capacity, high conductivity, low cost and earth abundant inherence. However, there still exists some disadvantages limiting its further applications, such as the tedious fabrication process, limited metal-ion transport kinetics and undesired structure deformation at harsh electrochemical conditions. Herein, we report a facile strategy, with calcium gluconate firstly reported as the carbon source, to fabricate ultrathin porous carbon nanosheets. <a>The as-prepared Ca-900 electrode delivers excellent K-ion storage performance including high reversible capacity (430.7 mAh g-1), superior rate capability (154.8 mAh g-1 at an ultrahigh current density of 5.0 A g-1) and ultra-stable long-term cycling stability (a high capacity retention ratio of ~81.2% after 4000 cycles at 1.0 A g-1). </a>Similarly, when being applied in Zn-ion capacitors, the Ca-900 electrode also exhibits an ultra-stable cycling performance with ~90.9% capacity retention after 4000 cycles at 1.0 A g-1, illuminating the applicable potentials. Moreover, the origin of the fast and smooth metal-ion storage is also revealed by carefully designed consecutive CV measurements. Overall, considering the facile preparation strategy, unique structure, application flexibility and in-depth mechanism investigations, this work will deepen the fundamental understandings and boost the commercialization of high-efficient energy storage devices like potassium-ion/sodium-ion batteries, zinc-ion batteries/capacitors and aluminum-ion batteries.

Download Full-text

Further Evidence for Energy Landscape Flattening in the Superionic Argyrodites Li6+xP1−xMxS5I (M = Si, Ge, Sn)

10.26434/chemrxiv.8109506.v2 ◽

2019 ◽

Author(s):

Saneyuki Ohno ◽

Bianca Helm ◽

Till Fuchs ◽

Georg Dewald ◽

Marvin Kraft ◽

...

Keyword(s):

Solid State ◽

Activation Barrier ◽

Energy Landscape ◽

General Mechanism ◽

Ionic Conductors ◽

Energy Storage Devices ◽

Ion Conductor ◽

Storage Devices ◽

Open Questions ◽

Sudden Decrease

All-solid-state batteries are promising candidates for next-generation energy storage devices. Although the list of candidate materials for solid electrolytes has grown in the past decade, there are still many open questions concerning the mechanisms behind ionic migration in materials. In particular, the lithium thiophosphate family of materials has shown very promising properties for solid-state battery applications. Recently, the Ge-substituted Li6PS5I argyrodite was shown to be a very fast Li-ion conductor, despite the poor ionic conductivity of the unsubstituted Li6PS5I. Therein, the conductivity was enhanced by over three orders of magnitude due to the emergence of I−/S2−exchange, i.e.site-disorder, which led to a sudden decrease of the activation barrier with a concurrent flattening of the energy landscapes. Inspired by this work, two series of elemental substitutions in Li6+xP1−xMxS5I (M= Si and Sn) were investigated in this study and compared to the Ge-analogue. A sharp reduction in the activation energy was observed at the same M4+/P5+composition as previously found in the Ge-analogue, suggesting a more general mechanism at play. Furthermore, structural analyses with X-ray and neutron diffraction indicate that similar changes in the Li-sublattice occur despite a significant variation in the size of the substituents, suggesting that in the argyrodites, the lithium substructure is most likely influenced by the occurring Li+– Li+interactions. This work provides further evidence that the energy landscape of ionic conductors can be tailored by inducing local disorder.

Download Full-text