Papers by Zhumabay Bakenov
Nanomaterials, 2020
Low dimensional Si-based materials are very promising anode candidates for the next-generation li... more Low dimensional Si-based materials are very promising anode candidates for the next-generation lithium-ion batteries. However, to satisfy the ever-increasing demand in more powerful energy storage devices, electrodes based on Si materials should display high-power accompanied with low volume change upon operation. Thus far, there were no reports on the Si-based materials which satisfy the stated requirements. Hence, here, we report on modified onion-structured Si nanoparticles (SiNPs) co-coated with Li4Ti5O12 (LTO) and cyclized polyacrylonitrile (cPAN) to bring the synergistic effect enhancing the conductivity, tolerance to volume change and stable performance. Obtained results suggest that the nanoparticles were conformally coated with both materials simultaneously and the thicknesses of the films were in a range of a few nanometers. Electrochemical tests show that the modified SiNPs deliver a high initial capacity of 2443 mAh g−1 and stable capacity retention over 50 cycles with 9...
Scientific Reports
Zinc oxide (ZnO) is one of the most promising metal oxide semiconductor materials, particularly f... more Zinc oxide (ZnO) is one of the most promising metal oxide semiconductor materials, particularly for optical and gas sensing applications. The influence of thickness and solvent on various features of ZnO thin films deposited at ambient temperature and barometric pressure by the sequential ionic layer adsorption and reaction method (SILAR) was carefully studied in this work. Ethanol and distilled water (DW) were alternatively used as a solvent for preparation of ZnO precursor solution. Superficial morphology, crystallite structure, optical and electrical characteristics of the thin films of various thickness are examined applying X-ray diffraction (XRD) system, scanning electron microscopy, the atomic force microscopy, X-ray photoelectron spectroscopy, ultraviolet–visible spectroscopy, photoluminescence spectroscopy, Hall effect measurement analysis and UV response study. XRD analysis confirmed that thin films fabricated using ethanol or DW precursor solvents are hexagonal wurtzite Z...
Nanoscale Research Letters
Harvesting abundant mechanical energy has been considered one of the promising technologies for d... more Harvesting abundant mechanical energy has been considered one of the promising technologies for developing autonomous self-powered active sensors, power units, and Internet-of-Things devices. Among various energy harvesting technologies, the triboelectric harvesters based on contact electrification have recently attracted much attention because of their advantages such as high performance, light weight, and simple design. Since the first triboelectric energy-harvesting device was reported, the continuous investigations for improving the output power have been carried out. This review article covers various methods proposed for the performance enhancement of triboelectric nanogenerators (TENGs), such as a triboelectric material selection, surface modification through the introduction of micro-/nano-patterns, and surface chemical functionalization, injecting charges, and their trapping. The main purpose of this work is to highlight and summarize recent advancements towards enhancing t...
Nanomaterials (Basel, Switzerland), Jan 26, 2018
A simple and effective method was developed to obtain the electrode for lithium/sulfur (Li/S) bat... more A simple and effective method was developed to obtain the electrode for lithium/sulfur (Li/S) batteries with high specific capacity and cycling durability via adopting an interconnected sulfur/activated carbon/graphene (reduced graphene oxide) aerogel (S/AC/GA) cathode architecture. The AC/GA composite with a well-defined interconnected conductive network was prepared by a reduction-induced self-assembly process, which allows for obtaining compact and porous structures. During this process, reduced graphene oxide (RGO) was formed, and due to the presence of oxygen-containing functional groups on its surface, it not only improves the electronic conductivity of the cathode but also effectively inhibits the polysulfides dissolution and shuttle. The introduced activated carbon allowed for lateral and vertical connection between individual graphene sheets, completing the formation of a stable three-dimensionally (3D) interconnected graphene framework. Moreover, a high specific surface ar...
Frontiers in Energy Research, 2015
Although sulfur has a high theoretical gravimetric capacity, 1672 mAh/g, its insulating nature re... more Although sulfur has a high theoretical gravimetric capacity, 1672 mAh/g, its insulating nature requires a large amount of conducting additives: this tends to result in a low massloading of active material (sulfur), and thereby, a lower capacity than expected. Therefore, an optimal choice of conducting agents and of the method for sulfur/conductingagent integration is critically important. In this paper, we report that the areal capacity of 4.9 mAh/cm 2 was achieved at sulfur mass loading of 4.1 mg/cm 2 by casting sulfur/polyacrylonitrile/ketjenblack (S/PAN/KB) cathode composite into carbon fiber paper. This is the highest value among published/reported ones even though it does not contain expensive nanosized carbon materials such as carbon nanotubes, graphene, or graphene derivatives, and competitive enough with the conventional LiCoO 2-based cathodes (e.g., LiCoO 2 , <20 mg/cm 2 corresponding to <2.8 mAh/cm 2). Furthermore, the combination of sulfur/PAN-based composite and PAN-based carbon fiber paper enabled the sulfurbased composite to be used even in carbonate-based electrolyte solution that many lithium/sulfur battery researchers avoid the use of it because of severer irreversible active material loss than in electrolyte solutions without carbonate-based solutions, and even at the highest mass-loading ever reported (the more sulfur is loaded, the more decomposed sulfides deposit at an anode surface).
Sensors
With the increase of interest in the application of piezoelectric polyvinylidene fluoride (PVDF) ... more With the increase of interest in the application of piezoelectric polyvinylidene fluoride (PVDF) in nanogenerators (NGs), sensors, and microdevices, the most efficient and suitable methods of their synthesis are being pursued. Electrospinning is an effective method to prepare higher content β-phase PVDF nanofiber films without additional high voltage poling or mechanical stretching, and thus, it is considered an economically viable and relatively simple method. This work discusses the parameters affecting the preparation of the desired phase of the PVDF film with a higher electrical output. The design and selection of optimum preparation conditions such as solution concentration, solvents, the molecular weight of PVDF, and others lead to electrical properties and performance enhancement in the NG, sensor, and other applications. Additionally, the effect of the nanoparticle additives that showed efficient improvements in the PVDF films was discussed as well. For instance, additives o...
In this paper, economical comparison is conducted among non-toxic, non-flammable rechargeable bat... more In this paper, economical comparison is conducted among non-toxic, non-flammable rechargeable batteries for integrating renewable energy into electrical grids. Two types of recently developed aqueous batteries, “flow assisted Zn/NiOOH battery” and “half capacitor - half battery” (AC/NiOOH and AC/NaMnO2, AC denotes activated carbon. The AC electrode can be considered “a half capacitor,” and the NiOOH or NaMnO2 electrode can be considered “a half battery”), are introduced and analyzed. These new energy storage devices offer less expensive solutions for large scale energy storage than conventional ones such as lithium-ion batteries, lead-acid batteries, vanadium redox flow batteries, and nickel metal hydride batteries. A newly started aqueous battery development, flow-assist-free Zn/NiOOH battery is also presented.
The olivine structured mixed lithium-transition metal phosphates LiMPO4 (M = Fe, Mn, Co) have att... more The olivine structured mixed lithium-transition metal phosphates LiMPO4 (M = Fe, Mn, Co) have attracted
tremendous attention of many research teams worldwide as a promising cathode materials for lithium batteries. Among
them, lithium manganese phosphate LiMnPO4 is the most promising considering its high theoretical capacity and
operating voltage, low cost and environmental safety. Various techniques were applied to prepare this perspective cathode
for lithium batteries. The solution based synthetic routes such as spray pyrolysis, precipitation, sol-gel, hydrothermal and
polyol synthesis allow preparing nanostructured powders of LiMnPO4 with enhanced electrochemical properties, which is
mostly attributed to the higher chemical homogeneity and narrow particle size distribution of the material. Up-to-date, the
LiMnPO4/C composites prepared by the spray pyrolysis route have the best electrochemical performance among the
reported in the literature.
Although sulfur has a high theoretical gravimetric capacity, 1672 mAh/g, its insulating
nature re... more Although sulfur has a high theoretical gravimetric capacity, 1672 mAh/g, its insulating
nature requires a large amount of conducting additives: this tends to result in a low massloading
of active material (sulfur), and thereby, a lower capacity than expected. Therefore,
an optimal choice of conducting agents and of the method for sulfur/conductingagent
integration is critically important. In this paper, we report that the areal capacity
of 4.9 mAh/cm2 was achieved at sulfur mass loading of 4.1 mg/cm2 by casting sulfur/
polyacrylonitrile/ketjenblack (S/PAN/KB) cathode composite into carbon fiber paper.
This is the highest value among published/reported ones even though it does not contain
expensive nanosized carbon materials such as carbon nanotubes, graphene, or graphene
derivatives, and competitive enough with the conventional LiCoO2-based cathodes (e.g.,
LiCoO2, <20 mg/cm2 corresponding to <2.8 mAh/cm2). Furthermore, the combination
of sulfur/PAN-based composite and PAN-based carbon fiber paper enabled the sulfurbased
composite to be used even in carbonate-based electrolyte solution that many
lithium/sulfur battery researchers avoid the use of it because of severer irreversible active
material loss than in electrolyte solutions without carbonate-based solutions, and even at
the highest mass-loading ever reported (the more sulfur is loaded, the more decomposed
sulfides deposit at an anode surface).
Potassium nickel hexacyanoferrate KNi[Fe(CN)6] (NiHCF) was synthesized by a simple co-precipitati... more Potassium nickel hexacyanoferrate KNi[Fe(CN)6] (NiHCF) was synthesized by a simple co-precipitation
method and investigated as a cathode material for lithium-ion batteries. The X-ray diffraction and
transmission electron microscopy studies revealed the formation of pure phase of agglomerated NiHCF
nanoparticles of about 20–50 nm in size. The material exhibited stable cycling performance as a cathode
in a lithium half-cell within a wide range of current densities, and a working potential around 3.3 V vs. Li+/
Li. The lithium ion diffusion coefficient in this system was determined to be in a range of 109 to 108 cm2
s1, which is within the values for the cathode materials for lithium-ion batteries with high rate
capability. Considering promising electrochemical performance and attractive lithium-ion diffusion
properties of this material along with its economical benefits and simplified preparation, NiHCF could be
considered as a very promising cathode for large scale lithium-ion batteries.
A free-standing sulfur/nitrogen-doped carbon nanotube (S/N-CNT) composite prepared via a simple s... more A free-standing sulfur/nitrogen-doped carbon nanotube (S/N-CNT) composite prepared via a simple solution
method was first studied as a cathode material for lithium/sulfur batteries. By taking advantage of the self-weaving
behavior of N-CNT, binders and current collectors are rendered unnecessary in the cathode, thereby simplifying its
manufacturing and increasing the sulfur weight ratio in the electrode. Transmission electronic microscopy showed
the formation of a highly developed core-shell tubular structure consisting of S/N-CNT composite with uniform
sulfur coating on the surface of N-CNT. As a core in the composite, the N-CNT with N functionalization provides a
highly conductive and mechanically flexible framework, enhancing the electronic conductivity and consequently
the rate capability of the material.
High specific energy and low cost flexible lithium/sulfur batteries have attracted significant
at... more High specific energy and low cost flexible lithium/sulfur batteries have attracted significant
attention as a promising power source to enable future flexible and wearable electronic
devices. Here, we review recent progress in the development of free-standing sulfur composite
cathodes, with special emphasis on electrode material selectivity and battery structural
design.The mini-review is organized based on the dimensionality of different scaffold
materials, namely one-dimensional carbon nanotube (CNT), two-dimensional graphene,
and three-dimensional CNT/graphene composite, respectively. Finally, the opportunities
and perspectives of the future research directions are discussed.
tComputational fluid dynamics (CFD) has been incorporated into a chemical engineering curriculum ... more tComputational fluid dynamics (CFD) has been incorporated into a chemical engineering curriculum at the interme-diate undergraduate level. CFD has now become a component of professional life in engineering practice and toprepare students properly, they must get exposure to all aspects of their chosen profession. Issues of concern arisewhen mathematical modelling is being introduced into a curriculum. For example, at the practical level, it mustbe considered whether or not an appropriate platform has been developed to allow the students to use the soft-ware efficiently and importantly without frustration. Also it is important that students have been taught sufficientskills for the student to continue with simulations in a systematic and methodical manner. The incorporation of theCFD package into a traditional chemical engineering curriculum is described here, and evaluation results based onpre–post knowledge and skill experiments, and student survey results document successful learning outcomes andeffectiveness of the approach.
Safety is an indispensable feature for a battery particularly in large scale applications. In thi... more Safety is an indispensable feature for a battery particularly in large scale applications. In this respect, gel electrolytes are more attractive due to less possibility of electrolyte leakage and safer if abused. Unfortunately, most present gel electrolyte systems are mainly based on polyethers which supposed to be flammable. In addition, PEO and PPO based systems exhibit a low cation transference number. Therefore, the seeking of novel thermally stable and safety polymer electrolytes with improved electrochemical behaviour is crucial. In the present contribution, we propose a series of Li-ion conducting polymer electrolytes based on the poly(ethyleneglycol) (PEG) borate ester (PE-350B) and PEG-methacrylates (PME-400 and PDE-600, respectively) plasticized by M550B100 PEG-borate ester, which can be characterized as a thermally stable solvent with high flash point [1].
Journal of The Electrochemical Society
ABSTRACT The composite cathode was successfully prepared by a combination of spray pyrolysis and ... more ABSTRACT The composite cathode was successfully prepared by a combination of spray pyrolysis and wet ballmilling with heat-treatment. The composite cathode had narrow particle size distribution with an average particle size of 99 nm. The Mg doping on the Mn site led to the electrochemical performance enhancement of the composite cathode, which was confirmed by cyclic voltammetry, ac impedance spectroscopy, and charge–discharge tests. The Mg-doped composite cathode exhibited a high discharge capacity in lithium cell, which remarkably increased with an increase in the charge cutoff voltage under galvanostatic charge–discharge. The cathode exhibited a discharge capacity of (above 93% of the theoretical value) at 0.1C when charge–discharged galvanostatically to 4.9 V. Along with enhanced discharge capacity, the cell exhibited a good rate capability under the galvanostatic charge–discharge. Under the trickle mode conditions, the cell exhibited discharge capacities of 154, 136, 106, and at 0.05, 0.1, 1, and 5C, respectively.
In this paper, economical comparison is conducted among non-toxic, non-flammable rechargeable bat... more In this paper, economical comparison is conducted among non-toxic, non-flammable rechargeable batteries for integrating renewable energy into electrical grids. Two types of recently developed aqueous batteries, “flow assisted Zn/NiOOH battery” and “half capacitor - half battery” (AC/NiOOH and AC/NaMnO2, AC denotes activated carbon. The AC electrode can be considered “a half capacitor,” and the NiOOH or NaMnO2 electrode can be considered “a half battery”), are introduced and analyzed. These new energy storage devices offer less expensive solutions for large scale energy storage than conventional ones such as lithium-ion batteries, lead-acid batteries, vanadium redox flow batteries, and nickel metal hydride batteries. A newly started aqueous battery development, flow-assist-free Zn/NiOOH battery is also presented.
Lithium sulfur battery is a promising candidate for the next generation rechargeable battery sinc... more Lithium sulfur battery is a promising candidate for the next generation rechargeable battery since the negative electrode, lithium, and the cathode, sulfur, have the highest theoretical capacities of 3862 and of 1672 mAh/g, respectively, among any other active materials, e.g., graphite (372 mAh/g) or LiCoO2 (274 mAh/g, only about 50% is practically available). However, there are several challenging issues in order to realize the use of this type of next generation battery. First, the lithium metal anode has an intrinsic safety issue, dendrite growth that can result in internal short circuit failure. Second, the sulfur cathode is a very insulating material; therefore, sulfur-based cathodes need a large amount of conducting additives, resulting in the decrease in the practically available gravimetric capacity per the unit mass of cathode composite. Third, lithium polysulfides, reduced (discharged) forms of sulfur, dissolve into an electrolyte solution, resulting in capacity fading. Fo...
Uploads
Papers by Zhumabay Bakenov
tremendous attention of many research teams worldwide as a promising cathode materials for lithium batteries. Among
them, lithium manganese phosphate LiMnPO4 is the most promising considering its high theoretical capacity and
operating voltage, low cost and environmental safety. Various techniques were applied to prepare this perspective cathode
for lithium batteries. The solution based synthetic routes such as spray pyrolysis, precipitation, sol-gel, hydrothermal and
polyol synthesis allow preparing nanostructured powders of LiMnPO4 with enhanced electrochemical properties, which is
mostly attributed to the higher chemical homogeneity and narrow particle size distribution of the material. Up-to-date, the
LiMnPO4/C composites prepared by the spray pyrolysis route have the best electrochemical performance among the
reported in the literature.
nature requires a large amount of conducting additives: this tends to result in a low massloading
of active material (sulfur), and thereby, a lower capacity than expected. Therefore,
an optimal choice of conducting agents and of the method for sulfur/conductingagent
integration is critically important. In this paper, we report that the areal capacity
of 4.9 mAh/cm2 was achieved at sulfur mass loading of 4.1 mg/cm2 by casting sulfur/
polyacrylonitrile/ketjenblack (S/PAN/KB) cathode composite into carbon fiber paper.
This is the highest value among published/reported ones even though it does not contain
expensive nanosized carbon materials such as carbon nanotubes, graphene, or graphene
derivatives, and competitive enough with the conventional LiCoO2-based cathodes (e.g.,
LiCoO2, <20 mg/cm2 corresponding to <2.8 mAh/cm2). Furthermore, the combination
of sulfur/PAN-based composite and PAN-based carbon fiber paper enabled the sulfurbased
composite to be used even in carbonate-based electrolyte solution that many
lithium/sulfur battery researchers avoid the use of it because of severer irreversible active
material loss than in electrolyte solutions without carbonate-based solutions, and even at
the highest mass-loading ever reported (the more sulfur is loaded, the more decomposed
sulfides deposit at an anode surface).
method and investigated as a cathode material for lithium-ion batteries. The X-ray diffraction and
transmission electron microscopy studies revealed the formation of pure phase of agglomerated NiHCF
nanoparticles of about 20–50 nm in size. The material exhibited stable cycling performance as a cathode
in a lithium half-cell within a wide range of current densities, and a working potential around 3.3 V vs. Li+/
Li. The lithium ion diffusion coefficient in this system was determined to be in a range of 109 to 108 cm2
s1, which is within the values for the cathode materials for lithium-ion batteries with high rate
capability. Considering promising electrochemical performance and attractive lithium-ion diffusion
properties of this material along with its economical benefits and simplified preparation, NiHCF could be
considered as a very promising cathode for large scale lithium-ion batteries.
method was first studied as a cathode material for lithium/sulfur batteries. By taking advantage of the self-weaving
behavior of N-CNT, binders and current collectors are rendered unnecessary in the cathode, thereby simplifying its
manufacturing and increasing the sulfur weight ratio in the electrode. Transmission electronic microscopy showed
the formation of a highly developed core-shell tubular structure consisting of S/N-CNT composite with uniform
sulfur coating on the surface of N-CNT. As a core in the composite, the N-CNT with N functionalization provides a
highly conductive and mechanically flexible framework, enhancing the electronic conductivity and consequently
the rate capability of the material.
attention as a promising power source to enable future flexible and wearable electronic
devices. Here, we review recent progress in the development of free-standing sulfur composite
cathodes, with special emphasis on electrode material selectivity and battery structural
design.The mini-review is organized based on the dimensionality of different scaffold
materials, namely one-dimensional carbon nanotube (CNT), two-dimensional graphene,
and three-dimensional CNT/graphene composite, respectively. Finally, the opportunities
and perspectives of the future research directions are discussed.
tremendous attention of many research teams worldwide as a promising cathode materials for lithium batteries. Among
them, lithium manganese phosphate LiMnPO4 is the most promising considering its high theoretical capacity and
operating voltage, low cost and environmental safety. Various techniques were applied to prepare this perspective cathode
for lithium batteries. The solution based synthetic routes such as spray pyrolysis, precipitation, sol-gel, hydrothermal and
polyol synthesis allow preparing nanostructured powders of LiMnPO4 with enhanced electrochemical properties, which is
mostly attributed to the higher chemical homogeneity and narrow particle size distribution of the material. Up-to-date, the
LiMnPO4/C composites prepared by the spray pyrolysis route have the best electrochemical performance among the
reported in the literature.
nature requires a large amount of conducting additives: this tends to result in a low massloading
of active material (sulfur), and thereby, a lower capacity than expected. Therefore,
an optimal choice of conducting agents and of the method for sulfur/conductingagent
integration is critically important. In this paper, we report that the areal capacity
of 4.9 mAh/cm2 was achieved at sulfur mass loading of 4.1 mg/cm2 by casting sulfur/
polyacrylonitrile/ketjenblack (S/PAN/KB) cathode composite into carbon fiber paper.
This is the highest value among published/reported ones even though it does not contain
expensive nanosized carbon materials such as carbon nanotubes, graphene, or graphene
derivatives, and competitive enough with the conventional LiCoO2-based cathodes (e.g.,
LiCoO2, <20 mg/cm2 corresponding to <2.8 mAh/cm2). Furthermore, the combination
of sulfur/PAN-based composite and PAN-based carbon fiber paper enabled the sulfurbased
composite to be used even in carbonate-based electrolyte solution that many
lithium/sulfur battery researchers avoid the use of it because of severer irreversible active
material loss than in electrolyte solutions without carbonate-based solutions, and even at
the highest mass-loading ever reported (the more sulfur is loaded, the more decomposed
sulfides deposit at an anode surface).
method and investigated as a cathode material for lithium-ion batteries. The X-ray diffraction and
transmission electron microscopy studies revealed the formation of pure phase of agglomerated NiHCF
nanoparticles of about 20–50 nm in size. The material exhibited stable cycling performance as a cathode
in a lithium half-cell within a wide range of current densities, and a working potential around 3.3 V vs. Li+/
Li. The lithium ion diffusion coefficient in this system was determined to be in a range of 109 to 108 cm2
s1, which is within the values for the cathode materials for lithium-ion batteries with high rate
capability. Considering promising electrochemical performance and attractive lithium-ion diffusion
properties of this material along with its economical benefits and simplified preparation, NiHCF could be
considered as a very promising cathode for large scale lithium-ion batteries.
method was first studied as a cathode material for lithium/sulfur batteries. By taking advantage of the self-weaving
behavior of N-CNT, binders and current collectors are rendered unnecessary in the cathode, thereby simplifying its
manufacturing and increasing the sulfur weight ratio in the electrode. Transmission electronic microscopy showed
the formation of a highly developed core-shell tubular structure consisting of S/N-CNT composite with uniform
sulfur coating on the surface of N-CNT. As a core in the composite, the N-CNT with N functionalization provides a
highly conductive and mechanically flexible framework, enhancing the electronic conductivity and consequently
the rate capability of the material.
attention as a promising power source to enable future flexible and wearable electronic
devices. Here, we review recent progress in the development of free-standing sulfur composite
cathodes, with special emphasis on electrode material selectivity and battery structural
design.The mini-review is organized based on the dimensionality of different scaffold
materials, namely one-dimensional carbon nanotube (CNT), two-dimensional graphene,
and three-dimensional CNT/graphene composite, respectively. Finally, the opportunities
and perspectives of the future research directions are discussed.