Ga-Doped LLZO Solid-State Electrolyte with Unique ``Plate-like'' Morphology Derived from Water Hyacinth (Eichhornia crassipes) Aquatic Weed: Waste to Wealth Conversion

An attempt has been made for the first time to convert waste biomass such as water hyacinth (WH) to a functional energy material in a cost-effective way. The present research describes a novel exo-templating methodology to develop engineered microstructure of Ga-doped Li7La3Zr2O12 (Li6.25La3Ga0.25Zr2O12, referred as WH-Ga-LLZO) solid-state electrolyte for its use in all solid-state lithium batteries (ASSLBs) by mimicking the intercellular structure of water hyacinth (Eichhornia crassipes), an invasive and noxious aquatic plant. The developed exo-templated methodology offers a low calcination temperature of 1000 degrees C in air where all the major peaks could be indexed as cubic garnet, as confirmed by XRD. The FESEM micrographs revealed a unique ``plate-like'' morphology that mimicked the intercellular structure of water hyacinth fiber. The bulk lithium-ion conductivity in the WH-Ga-LLZO electrolyte was found to be 3.94 x 10(-5) S/cm. Li/WH-Ga-LLZO/Li cells were galvanostatically cycled for a continuous 295 h with increasing step current densities from 28 mu A/cm(3) without a short circuit. The highest current density as measured for maximum polarization in a symmetric cell was found to be 452 mu A/cm(2). The WH exotemplated methodology was thus developed and optimized and can be extended for synthesizing any application-specific multifunctional materials

Engineered Li7La3Zr2O12 (LLZO) for Pseudo-Solid-State Lithium Metal Batteries (SSLMBs): Tailor-Made Synthesis, Evolution of the Microstructure, Suppression of Dendritic Growth, and Enhanced Electrochemical Performance

Morphologically engineered Li7La3Zr2O12 (LLZO) impregnated with a common solvated ionic liquid (SIL) can greatly influence the cycling performance (360 cycles), coulombic efficiency (>99%), and high rate capability (0.05-1.2 mA center dot cm-2) of pseudo-solid-state lithium metal batteries (SSLMBs). In this report, to obtain a unique microstructure of cubic-LLZO, a fine-tuned combustion synthesis process was first designed; synthetic parameters were duly optimized, and powders were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR),1H NMR, and Raman spectroscopy. An in-depth analysis of powder properties and electrochemical behavior of the fabricated SSLM cells revealed that impurities present in LLZO significantly facilitated electrochemical cell performances. Such a combination of the engineered LLZO impregnated with the SIL enabled the plating and stripping cycles in Li symmetric cells with up to 200 h of operation at a constant current density of 0.05 mA center dot cm-2 avoiding short circuit. The critical current density (CCD) was found to be 450 mu A cm-2, which is significantly higher than the other reported CCD values for pristine LLZO. The post-electrochemical study revealed that transgranular lithium dendritic growth, a genuine problem in SSLMBs, was impeded to a significant extent by the engineered LLZO and an in situ formed phase, Li0.5Al0.5La2O4, at grain boundaries during cycling. The multicathode compatibility tests as performed (Li/LLZO-SIL/LMO, Li/ LLZO-SIL/LFP, and Li/LLZO-SIL/NMC111) exhibited that morphologically altered LLZO with the SIL interface is compatible with most of the commercial cathodes. The study thus envisaged that the engineered LLZO solid electrolyte impregnated with the SIL can exert a synergistic effect to enhance faster Li-ion conduction as well as resistance to Li dendritic growth, providing a path for developing high-performance SSLMBs

Engineered Li₇La₃Zr₂O₁₂ (LLZO) for Pseudo-Solid-State Lithium Metal Batteries (SSLMBs): Tailor-Made Synthesis, Evolution of the Microstructure, Suppression of Dendritic Growth, and Enhanced Electrochemical Performance

Morphologically engineered Li7La3Zr2O12 (LLZO) impregnated with a common solvated ionic liquid (SIL) can greatly influence the cycling performance (360 cycles), coulombic efficiency (>99%), and high rate capability (0.05–1.2 mA·cm–2) of pseudo-solid-state lithium metal batteries (SSLMBs). In this report, to obtain a unique microstructure of cubic-LLZO, a fine-tuned combustion synthesis process was first designed; synthetic parameters were duly optimized, and powders were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR), 1H NMR, and Raman spectroscopy. An in-depth analysis of powder properties and electrochemical behavior of the fabricated SSLM cells revealed that impurities present in LLZO significantly facilitated electrochemical cell performances. Such a combination of the engineered LLZO impregnated with the SIL enabled the plating and stripping cycles in Li symmetric cells with up to 200 h of operation at a constant current density of 0.05 mA·cm–2 avoiding short circuit. The critical current density (CCD) was found to be 450 μA cm–2, which is significantly higher than the other reported CCD values for pristine LLZO. The post-electrochemical study revealed that transgranular lithium dendritic growth, a genuine problem in SSLMBs, was impeded to a significant extent by the engineered LLZO and an in situ formed phase, Li0.5Al0.5La2O4, at grain boundaries during cycling. The multicathode compatibility tests as performed (Li/LLZO-SIL/LMO, Li/LLZO-SIL/LFP, and Li/LLZO-SIL/NMC111) exhibited that morphologically altered LLZO with the SIL interface is compatible with most of the commercial cathodes. The study thus envisaged that the engineered LLZO solid electrolyte impregnated with the SIL can exert a synergistic effect to enhance faster Li-ion conduction as well as resistance to Li dendritic growth, providing a path for developing high-performance SSLMBs

Filter paper templated interconnected nanocrystalline LiMn(2)O(4) with high coulombic efficiency and rate capability

A novel filter paper templating method has been developed to prepare nanocrystalline LiMn(2)O(4). Whatman 42 filter paper impregnated with the precursor gel produces ultrafine powder (80-100 nm) when calcined at 800 degrees C. The structure and morphology of the powder and the template have been studied in detail by X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). A single phase cubic spinel with interconnected powder morphology is found. The electrochemical properties have been studied using 2032 coin type cells in the potential window of 3.4 to 4.5 V versus Li/Li(+). Sharp oxidation-reduction peaks at 4.09/3.90V and 4.22/4.04V in the cyclic voltagram indicate high crystallinity and good reversibility of the cathode. A typical cell shows an initial discharge capacity of 97 mAh/g with similar to 98% columbic efficiency. Rate capability study of the synthesized cathode has been performed by cycling the cell for 130 cycles at different current densities (0.1-1.5 mA/cm(2)) and it is observed that 80-100% retention of initial capacity is possible when cycled at 0.1-0.6 mA/cm(2). A capacity fading of only 0.03 mAh/g per cycle is observed even at 1.5 mA/cm(2) (8C). Thus, we have shown that simple filter paper templating technique can produce nanocrystalline LiMn(2)O(4) with high coulombic efficiency (100-95%) and rate capability

Oxygen separation membrane derived from aquatic weed: A novel bio-inspired approach to synthesize BaBi0.2Co0.35Fe0.45O3-delta perovskite from water hyacinth (Eichhornia crassipes)

In recent years, bio-inspired synthesis processes have drawn increasing research interest as a new tool for designing next generation advanced functional materials with unparalleled advantages. Bio-inspired process offers unique microstructures which are difficult to engineer through conventional synthesis methodologies. The present study aims to develop a bio-templating process of synthesizing BaBi0.2Co0.35Fe0.45O3-delta (BBCF) perovskite type oxygen separation membrane mimicking the interior of water hyacinth's (Eichhornia crassipes) petioles. In Indian sub-continent water hyacinth is considered as one of the worst aquatic weed whose removal is necessary from natural water reservoir to save aquatic environment. The idea of using such water pollutant to produce engineered microstructure for improving material's functionality is the philosophy behind the present study. The exo-templating of water hyacinth results in interesting microstructure and enhanced the physical properties of BBCF membrane in terms of oxygen permeation flux. The novel, simple method may be extended to produce any multifunctional advanced material with a spectacular microstructure and unique properties. (C) 2016 Elsevier B.V. All rights reserved

Synthesis of BaBi0.2Co0.Fe-35(0).O-45(3-delta) by a novel aqueous soft chemical method and its characterizations

BaBi0.Co-2(0).Fe-35(0).O-45(3-delta)(BBCF) single phase perovskite has been successfully synthesized by a novel alanine assisted soft chemical combustion method. Thermal behavior of metal alanine complexes during combustion to form BBCF perovskite structure has been studied in detail. X- ray diffraction patterns reveal that the formation of single phase BBCF perovskite proceeds by formation of several intermediate phases. A single phase BBCF powder is obtained at a temperature of 950 degrees C. Homogeneous distribution of multiple dopants in BBCF matrix is confirmed by elemental mapping using FESEM. The electrical conductivity reveals that with the increase in sintering temperature, conductivity of BBCF increases, reaches to a maximum value of 10.38 S cm 1 at 800 degrees C when measured in air for samples sintered at 950 degrees C and upon further increase in sintering temperature, the conductivity decreases gradually. Up to 800 degrees C, BBCF shows a semiconducting behavior and subsequently follows metallic conduction above 800 degrees C while performing electrical conductivity measurement in air. (C) 2013 Elsevier B.V. All rights reserved

Zr- and Tb-doped barium cerate-based cermet membrane for hydrogen separation application

Ba0.8Ce0.35Zr0.5Tb0.15O3- (BCZT) perovskite has been synthesized by glycine-assisted solution combustion method. The Ni-Ba0.8Ce0.35Zr0.5Tb0.15O3--based cermet membrane is obtained by cosintering NiO and BCZT powder mixture at 1550 degrees C in reducing atmosphere. The X-ray diffraction pattern of sintered pellet shows the characteristic peaks of both Ni and BCZT phases. FESEM image and elemental mapping confirm the presence of randomly distributed metallic nickel in the BCZT matrix. An electrical conductivity of similar to 14S/cm at 700 degrees C is achieved in Ni-BCZT membrane, which reduced further with increase in temperature (>700 degrees C). The cermet membrane (1.5mm thick) shows a highest hydrogen permeation flux of similar to 0.07mL/min/cm(2) at 900 degrees C. Chemical stability of Ni-BCZT membrane has also been examined under humid and carbon dioxide containing atmosphere. The membrane shows good structural stability without any significant change in hydrogen permeation flux

Cellulose-ceramic composite flexible paper separator with improved wettability and flame retardant properties for lithium-ion batteries

In quest of developing sustainable separator for lithium-ion batteries (LIBs), this research focuses on functionalization of low cost cellulose based commercial paper using duo-polymer and nano-SiO2 by designing a facile aqueous based industry friendly wet-coating process. Unlike commercial plastic based polyolefin separators (polypropylene/polyethylene), the developed paper separator shows superior thermal stability > 200 degrees C without dimensional shrinkage, excellent electrolyte wettability (147%) with zero contact angle, quicker electrolyte saturation and satisfactory mechanical strength (34.86-38.31 MPa). The electrochemical performance carried out in 2032 coin cells using fabricated paper separators shows comparable performance to that of commercial polypropylene (PP) based separator at different current densities of 0.05-0.4 mA/cm(2) with excellent columbic efficiency (> 96%) and good capacity retention on cycling. The developed separator is found to be compatible with most of the commercial electrodes (MCMB, -LiCoO2, -LiFePO4) used in today's LIBs. The functionalized cellulose-ceramic composite paper separator shows excellent flame retardant properties by offering an added safety features for its successful use in lithiumion batteries

Filter paper derived cross-linked interconnected BaBi0.2Co0.35Fe0.45O3-delta morphology with an enhanced oxygen permeation property

This study aims to investigate the effect of an engineered microstructure on the oxygen permeation property of a BaBi0.2Co0.35Fe0.45O3-delta (BBCF) type perovskite membrane. The interconnected multi-level cross-linked structure of the BBCF membrane has been synthesized by mimicking a common laboratory grade filter paper. The controlled calcination of the cellulose matrix results in a single phase BBCF structure when calcined at 950 degrees C in air. The average diameter of the interconnected BBCF fiber is about 1 mu m as confirmed by FESEM. The electrical conductivity is measured to be similar to 20 S cm(-1) at 800 degrees C, higher than that of other conventionally prepared BBCF based membranes. The perovskite membrane derived by exo-templating of the filter paper's cellulose fiber reveals an enhanced oxygen permeation flux of 0.98 ml min (1) cm (2) at 900 degrees C