Materials for Energy Harvesting and Storage

Journal Name	Impact Factor	CiteScore	Launched Year	First Decision (median)	APC
Batteries batteries	4.0	5.4	2015	17.7 Days	CHF 2700
Designs designs	-	3.2	2017	16.4 Days	CHF 1600
Energies energies	3.2	5.5	2008	16.1 Days	CHF 2600
Materials materials	3.4	5.2	2008	13.9 Days	CHF 2600
Sustainability sustainability	3.9	5.8	2009	18.8 Days	CHF 2400

12 pages, 533 KiB

Open AccessArticle

Partial Oxidation Synthesis of Prussian Blue Analogues for Thermo-Rechargeable Battery

by Yutaka Moritomo, Masato Sarukura, Hiroki Iwaizumi and Ichiro Nagai

Batteries 2023, 9(8), 393; https://doi.org/10.3390/batteries9080393 - 27 Jul 2023

Cited by 1 | Viewed by 975

A thermo-rechargeable battery or tertiary battery converts thermal energy into electric energy via an electrochemical Seebeck coefficient. The manufacturing of the tertiary batteries requires a pre-oxidation step to align and optimize the cathode and anode potentials. The pre-oxidation step, which is not part [...] Read more.

A thermo-rechargeable battery or tertiary battery converts thermal energy into electric energy via an electrochemical Seebeck coefficient. The manufacturing of the tertiary batteries requires a pre-oxidation step to align and optimize the cathode and anode potentials. The pre-oxidation step, which is not part of the secondary battery manufacturing process, makes the manufacturing of tertiary batteries complex and costly. To omit the pre-oxidation step, we used partially oxidized Prussian blue analogs, i.e., Na

_{x}

Co[Fe(CN)

_{6}

]

_{y}

zH

_{2}

O (Co-PBA) and Na

_{x}

Ni[Fe(CN)

_{6}

]

_{y}

zH

_{2}

O (Ni-PBA), as cathode and anode materials. The modified tertiary battery without the pre-oxidation step shows good thermal cyclability between 10

^{\circ}

C and 50

^{\circ}

C without detectable deterioration of the thermal voltage (

V_{cell}

) and discharge capacity (

Q_{cell}

). Full article

(This article belongs to the Topic Materials for Energy Harvesting and Storage)

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13 pages, 2348 KiB

Open AccessArticle

Assessment of the Suitability of Coke Material for Proppants in the Hydraulic Fracturing of Coals

by Tomasz Suponik, Krzysztof Labus and Rafał Morga

Materials 2023, 16(11), 4083; https://doi.org/10.3390/ma16114083 - 30 May 2023

Viewed by 1142

Abstract

To enhance the extraction of methane gas from coal beds, hydraulic fracturing technology is used. However, stimulation operations in soft rocks, such as coal beds, are associated with technical problems related mainly to the embedment phenomenon. Therefore, the concept of a novel coke-based [...] Read more.

To enhance the extraction of methane gas from coal beds, hydraulic fracturing technology is used. However, stimulation operations in soft rocks, such as coal beds, are associated with technical problems related mainly to the embedment phenomenon. Therefore, the concept of a novel coke-based proppant was introduced. The purpose of the study was to identify the source coke material for further processing to obtain a proppant. Twenty coke materials differing in type, grain size, and production method from five coking plants were tested. The values of the following parameters were determined for the initial coke: micum index 40; micum index 10; coke reactivity index; coke strength after reaction; and ash content. The coke was modified by crushing and mechanical classification, and the 3–1 mm class was obtained. This was enriched in heavy liquid with a density of 1.35 g/cm³. The crush resistance index and Roga index, which were selected as key strength parameters, and the ash content were determined for the lighter fraction. The most promising modified coke materials with the best strength properties were obtained from the coarse-grained (fraction 25–80 mm and greater) blast furnace and foundry coke. They had crush resistance index and Roga index values of at least 44% and at least 96%, respectively, and contained less than 9% ash. After assessing the suitability of coke material for proppants in the hydraulic fracturing of coal, further research will be needed to develop a technology to produce proppants with parameters compliant with the PN-EN ISO 13503-2:2010 standard. Full article

(This article belongs to the Topic Materials for Energy Harvesting and Storage)

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14 pages, 3400 KiB

Open AccessArticle

Analysis of Forest Biomass Wood Briquette Structure According to Different Tests of Density

by Kamil Roman, Witold Rzodkiewicz and Marek Hryniewicz

Energies 2023, 16(6), 2850; https://doi.org/10.3390/en16062850 - 19 Mar 2023

Cited by 2 | Viewed by 1398

Abstract

X-ray technology is capable of non-destructively testing solid wood samples. The prepared wood briquette samples were identified by X-ray technology. The studies assessed the effect of biomass briquette structure by observing wood chip fractions under an X-ray. Study results show that X-ray technology [...] Read more.

X-ray technology is capable of non-destructively testing solid wood samples. The prepared wood briquette samples were identified by X-ray technology. The studies assessed the effect of biomass briquette structure by observing wood chip fractions under an X-ray. Study results show that X-ray technology is an effective tool for analyzing biomass wood-based materials, e.g., density, improving wood products quality and performance. The measurements are consistent with the true density, and chemical properties were measured from chosen material. In the article, a coefficient representing the picture density and true density of briquettes was proposed, and the comparison of both densities was based on the empirical measurements. Probably through an application of the conversion factor, the process of determining material densities could be simplified, cheaper, and quicker. Due to the conducted research, X-ray technology is an effective tool for improving wood products’ quality and performance. Combining X-ray technology with laboratory test results can provide quick and easy analysis. For example, the density comparison of shredded forest residues was defined. Based on the results, the mean value of the conversion factor was about 0.6. In addition, the observed results were compared with the doctoral research. Higher durability was found in briquettes with lower fractions of f₁ (31–68%) compared to the higher f₂, f₃, and f₄ (6–37%), which was approved in the spectrum picture. Full article

(This article belongs to the Topic Materials for Energy Harvesting and Storage)

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13 pages, 5396 KiB

Open AccessArticle

Comparative Performances of Natural Dyes Extracted from Mentha Leaves, Helianthus Annuus Leaves, and Fragaria Fruit for Dye-Sensitized Solar Cells

by Zainab Haider Abdulrahman, Dhafer Manea Hachim, Ahmed Salim Naser Al-murshedi, Furkan Kamil, Ahmed Al-Manea and Talal Yusaf

Designs 2022, 6(6), 100; https://doi.org/10.3390/designs6060100 - 25 Oct 2022

Cited by 3 | Viewed by 2290

Abstract

During the last four centuries, there have been extensive research activities looking for green and clean sources of energy instead of traditional (fossil) energy in order to reduce the accumulation of gases and environmental pollution. Natural dye-sensitized solar cells (DSSCs) are one of [...] Read more.

During the last four centuries, there have been extensive research activities looking for green and clean sources of energy instead of traditional (fossil) energy in order to reduce the accumulation of gases and environmental pollution. Natural dye-sensitized solar cells (DSSCs) are one of the most promising types of photovoltaic cells for generating clean energy at a low cost. In this study, DSSCs were collected and experimentally tested using four different dyes extracted from Mentha leaves, Helianthus annuus leaves, Fragaria, and a mixture of the above extracts in equal proportions as natural stimuli for TiO₂ films. The result show that solar energy was successfully turned into electricity. Additionally, DSSCs based on mixtures of dyes showed better results than those based on single dyes. Efficiency (η) was 0.714%, and the fill factor (FF) was 83.3% for the cell area. Full article

(This article belongs to the Topic Materials for Energy Harvesting and Storage)

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70 pages, 5257 KiB

Open AccessReview

Tug-of-War in the Selection of Materials for Battery Technologies

by Wendy Pantoja, Jaime Andres Perez-Taborda and Alba Avila

Batteries 2022, 8(9), 105; https://doi.org/10.3390/batteries8090105 - 24 Aug 2022

Cited by 8 | Viewed by 6402

Abstract

Batteries are the heart and the bottleneck of portable electronic systems. They power electronics and determine the system run time, with the size and volume determining factors in their design and implementation. Understanding the material properties of the battery components—anode, cathode, electrolyte, and [...] Read more.

Batteries are the heart and the bottleneck of portable electronic systems. They power electronics and determine the system run time, with the size and volume determining factors in their design and implementation. Understanding the material properties of the battery components—anode, cathode, electrolyte, and separator—and their interaction is necessary to establish selection criteria based on their correlations with the battery metrics: capacity, current density, and cycle life. This review studies material used in the four battery components from the perspective and the impact of seven ions (Li

^{+}

, Na

^{+}

, K

^{+}

, Zn

^{2 +}

, Ca

^{2 +}

, Mg

^{2 +}

, and Al

^{3 +}

), employed in commercial and research batteries. In addition, critical factors of sustainability of the supply chains—geographical raw materials origins vs. battery manufacturing companies and material properties (Young’s modulus vs. electric conductivity)—are mapped. These are key aspects toward identifying the supply chain vulnerabilities and gaps for batteries. In addition, two battery applications, smartphones and electric vehicles, in light of challenges in the current research, commercial fronts, and technical prospects, are discussed. Bringing the next generation of batteries necessitates a transition from advances in material to addressing the technical challenges, which the review has powered. Full article

(This article belongs to the Topic Materials for Energy Harvesting and Storage)

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9 pages, 2450 KiB

Open AccessArticle

Two Magnetic Orderings and a Spin–Flop Transition in Mixed Valence Compound Mn₃O(SeO₃)₃

by Wanwan Zhang, Meiyan Cui, Jindou Tian, Pengfeng Jiang, Guoyu Qian and Xia Lu

Materials 2022, 15(16), 5773; https://doi.org/10.3390/ma15165773 - 21 Aug 2022

Cited by 3 | Viewed by 1417

Abstract

A mixed-valence manganese selenite, Mn₃O(SeO₃)₃, was successfully synthesized using a conventional hydrothermal method. The three-dimensional framework of this compound is composed of an MnO₆ octahedra and an SeO₃ trigonal pyramid. The magnetic topological arrangement of [...] Read more.

A mixed-valence manganese selenite, Mn₃O(SeO₃)₃, was successfully synthesized using a conventional hydrothermal method. The three-dimensional framework of this compound is composed of an MnO₆ octahedra and an SeO₃ trigonal pyramid. The magnetic topological arrangement of manganese ions shows a three-dimensional framework formed by the intersection of octa-kagomé spin sublattices and staircase-kagomé spin sublattices. Susceptibility, magnetization and heat capacity measurements confirm that Mn₃O(SeO₃)₃ exhibits two successive long-range antiferromagnetic orderings with T_N1~4.5 K and T_N2~45 K and a field-induced spin–flop transition at a critical field of 4.5 T at low temperature. Full article

(This article belongs to the Topic Materials for Energy Harvesting and Storage)

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15 pages, 4646 KiB

Open AccessArticle

Thermal, Microstructural and Electrochemical Hydriding Performance of a Mg₆₅Ni₂₀Cu₅Y₁₀ Metallic Glass Catalyzed by CNT and Processed by High-Pressure Torsion

by Ádám Révész, Marcell Gajdics, Miratul Alifah, Viktória Kovács Kis, Erhard Schafler, Lajos Károly Varga, Stanislava Todorova, Tony Spassov and Marcello Baricco

Energies 2022, 15(15), 5710; https://doi.org/10.3390/en15155710 - 05 Aug 2022

Cited by 1 | Viewed by 1846

Abstract

A Mg₆₅Ni₂₀Cu₅Y₁₀ metallic glass was produced by melt spinning and was mixed with a 5 wt.% multiwall carbon nanotube additive in a high-energy ball mill. Subsequently, the composite mixture was exposed to high-pressure torsion deformation with [...] Read more.

A Mg₆₅Ni₂₀Cu₅Y₁₀ metallic glass was produced by melt spinning and was mixed with a 5 wt.% multiwall carbon nanotube additive in a high-energy ball mill. Subsequently, the composite mixture was exposed to high-pressure torsion deformation with different torsion numbers. Complimentary XRD and DSC experiments confirmed the exceptional structural and thermal stability of the amorphous phase against severe plastic deformation. Combined high-resolution transmission electron microscopy observations and fast Fourier transform analysis revealed deformation-induced Mg₂Ni nanocrystals, together with the structural and morphological stability of the nanotubes. The electrochemical hydrogen discharge capacity of the severely deformed pure metallic glass was substantially lower than that of samples with the nanotube additive for several cycles. It was also established that the most deformed sample containing nanotubes exhibited a drastic breakdown in the electrochemical capacity after eight cycles. Full article

(This article belongs to the Topic Materials for Energy Harvesting and Storage)

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12 pages, 4041 KiB

Open AccessArticle

Hierarchical and Heterogeneous Porosity Construction and Nitrogen Doping Enabling Flexible Carbon Nanofiber Anodes with High Performance for Lithium-Ion Batteries

by Jun Liu, Yuan Liu, Jiaqi Wang, Xiaohu Wang, Xuelei Li, Jingshun Liu, Ding Nan and Junhui Dong

Materials 2022, 15(13), 4387; https://doi.org/10.3390/ma15134387 - 21 Jun 2022

Cited by 1 | Viewed by 1458

Abstract

With the rapid development of flexible electronic devices, flexible lithium-ion batteries are widely considered due to their potential for high energy density and long life. Anode materials, as one of the key materials of lithium-ion batteries, need to have good flexibility, an excellent [...] Read more.

With the rapid development of flexible electronic devices, flexible lithium-ion batteries are widely considered due to their potential for high energy density and long life. Anode materials, as one of the key materials of lithium-ion batteries, need to have good flexibility, an excellent specific discharge capacity, and fast charge–discharge characteristics. Carbon fibers are feasible as candidate flexible anode materials. However, their low specific discharge capacity restricts their further application. Based on this, N-doped carbon nanofiber anodes with microporous, mesoporous, and macroporous structures are prepared in this paper. The hierarchical and heterogeneous porosity structure can increase the active sites of the anode material and facilitate the transport of ions, and N-doping can improve the conductivity. Moreover, the N-doped flexible carbon nanofiber with a porous structure can be directly used as the anode for lithium-ion batteries without adding an adhesive. It has a high first reversible capacity of 1108.9 mAh g⁻¹, a stable cycle ability (954.3 mAh g⁻¹ after 100 cycles), and excellent rate performance. This work provides a new strategy for the development of flexible anodes with high performance. Full article

(This article belongs to the Topic Materials for Energy Harvesting and Storage)

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10 pages, 2874 KiB

Open AccessArticle

The Effects of Ru⁴⁺ Doping on LiNi_0.5Mn_1.5O₄ with Two Crystal Structures

by Xinli Li, Ben Su, Wendong Xue and Junnan Zhang

Materials 2022, 15(12), 4273; https://doi.org/10.3390/ma15124273 - 16 Jun 2022

Cited by 2 | Viewed by 1753

Abstract

Doping of Ru has been used to enhance the performance of LiNi_0.5Mn_1.5O₄ cathode materials. However, the effects of Ru doping on the two types of LiNi_0.5Mn_1.5O₄ are rarely studied. In this study, Ru [...] Read more.

Doping of Ru has been used to enhance the performance of LiNi_0.5Mn_1.5O₄ cathode materials. However, the effects of Ru doping on the two types of LiNi_0.5Mn_1.5O₄ are rarely studied. In this study, Ru⁴⁺ with a stoichiometric ratio of 0.05 is introduced into LiNi_0.5Mn_1.5O₄ with different space groups (Fd

\bar{3}

m, P4₃32). The influence of Ru doping on the properties of LiNi_0.5Mn_1.5O₄ (Fd

\bar{3}

m, P4₃32) is comprehensively studied using multiple techniques such as XRD, Raman, and SEM methods. Electrochemical tests show that Ru⁴⁺-doped LiNi_0.5Mn_1.5O₄ (P4₃32) delivers the optimal electrochemical performance. Its initial specific capacity reaches 132.8 mAh g⁻¹, and 97.7% of this is retained after 300 cycles at a 1 C rate at room temperature. Even at a rate of 10 C, the capacity of Ru⁴⁺-LiNi_0.5Mn_1.5O₄ (P4₃32) is still 100.7 mAh g⁻¹. Raman spectroscopy shows that the Ni/Mn arrangement of Ru⁴⁺-LiNi_0.5Mn_1.5O₄ (Fd

\bar{3}

m) is not significantly affected by Ru⁴⁺ doping. However, LiNi_0.5Mn_1.5O₄ (P4₃32) is transformed to semi-ordered LiNi_0.5Mn_1.5O₄ after the incorporation of Ru⁴⁺. Ru⁴⁺ doping hinders the ordering process of Ni/Mn during the heat treatment process, to an extent. Full article

(This article belongs to the Topic Materials for Energy Harvesting and Storage)

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11 pages, 2548 KiB

Open AccessArticle

Boosting Lithium Storage of a Metal-Organic Framework via Zinc Doping

by Wenshan Gou, Zhao Xu, Xueyu Lin, Yifei Sun, Xuguang Han, Mengmeng Liu and Yan Zhang

Materials 2022, 15(12), 4186; https://doi.org/10.3390/ma15124186 - 13 Jun 2022

Cited by 3 | Viewed by 1872

Abstract

Lithium-ion batteries (LIBs) as a predominant power source are widely used in large-scale energy storage fields. For the next-generation energy storage LIBs, it is primary to seek the high capacity and long lifespan electrode materials. Nickel and purified terephthalic acid-based MOF (Ni-PTA) with [...] Read more.

Lithium-ion batteries (LIBs) as a predominant power source are widely used in large-scale energy storage fields. For the next-generation energy storage LIBs, it is primary to seek the high capacity and long lifespan electrode materials. Nickel and purified terephthalic acid-based MOF (Ni-PTA) with a series amounts of zinc dopant (0, 20, 50%) are successfully synthesized in this work and evaluated as anode materials for lithium-ion batteries. Among them, the 20% atom fraction Zn-doped Ni-PTA (Zn_0.2-Ni-PTA) exhibits a high specific capacity of 921.4 mA h g⁻¹ and 739.6 mA h g⁻¹ at different current densities of 100 and 500 mA g⁻¹ after 100 cycles. The optimized electrochemical performance of Zn_0.2-Ni-PTA can be attributed to its low charge transfer resistance and high lithium-ion diffusion rate resulting from expanded interplanar spacing after moderate Zn doping. Moreover, a full cell is fabricated based on the LiFePO₄ cathode and as-prepared MOF. The Zn_0.2-Ni-PTA shows a reversible specific capacity of 97.9 mA h g⁻¹ with 86.1% capacity retention (0.5 C) after 100 cycles, demonstrating the superior electrochemical performance of Zn_0.2-Ni-PTA anode as a promising candidate for practical lithium-ion batteries. Full article

(This article belongs to the Topic Materials for Energy Harvesting and Storage)

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10 pages, 2621 KiB

Open AccessArticle

Synthesis and Electrochemical Characterization of LiNi_0.5Co_0.2Mn_0.3O₂ Cathode Material by Solid-Phase Reaction

by Xinli Li, Ben Su, Wendong Xue and Junnan Zhang

Materials 2022, 15(11), 3931; https://doi.org/10.3390/ma15113931 - 31 May 2022

Cited by 1 | Viewed by 1296

Abstract

In this paper, using four carbonates as raw materials, the cathode material LiNi_0.5Co_0.2Mn_0.3O₂ was prepared with the “ball milling-calcining” solid-phase synthesis method. The specific reaction process, which consists of the decomposition of the raw materials and [...] Read more.

In this paper, using four carbonates as raw materials, the cathode material LiNi_0.5Co_0.2Mn_0.3O₂ was prepared with the “ball milling-calcining” solid-phase synthesis method. The specific reaction process, which consists of the decomposition of the raw materials and the generation of target products, was investigated thoroughly using the TG-DSC technique. XRD, SEM and charge/discharge test methods were utilized to explore the influence of different sintering temperatures on the structure, morphology and electrochemical performance of the LiNi_0.5Co_0.2Mn_0.3O₂ cathode. The results show that 900~1000 °C is the appropriate synthesis temperature range. LiNi_0.5Co_0.2Mn_0.3O₂ synthesized at 1000 °C delivers optimal cycling stability at 0.5 C. Meanwhile, its initial discharge specific capacity and coulomb efficiency reached 167.2 mAh g⁻¹ and 97.89%, respectively. In addition, the high-rate performance of the cathode sample prepared at 900 °C is particularly noteworthy. Cycling at 0.5 C, 1 C, 1.5 C and 2 C, the corresponding discharge specific capacity of the sample exhibited 148.1 mAh g⁻¹, 143.1 mAh g⁻¹, 140 mAh g⁻¹ and 138.9 mAh g⁻¹, respectively. Full article

(This article belongs to the Topic Materials for Energy Harvesting and Storage)

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13 pages, 2998 KiB

Open AccessArticle

Comparison of the Properties of Ni–Mn Hydroxides/Oxides with Ni–Mn Phosphates for the Purpose of Hybrid Supercapacitors

by Lyubomir Soserov, Delyana Marinova, Violeta Koleva, Antonia Stoyanova and Radostina Stoyanova

Batteries 2022, 8(6), 51; https://doi.org/10.3390/batteries8060051 - 30 May 2022

Cited by 7 | Viewed by 2741

Abstract

This study aims to quantify the synergistic effect of Ni²⁺ and Mn²⁺ ions on the capacitive performance of oxide, hydroxide and phosphate electrodes in alkaline electrolytes. Three types of phases containing both nickel and manganese in a ratio of one-to-one were [...] Read more.

This study aims to quantify the synergistic effect of Ni²⁺ and Mn²⁺ ions on the capacitive performance of oxide, hydroxide and phosphate electrodes in alkaline electrolytes. Three types of phases containing both nickel and manganese in a ratio of one-to-one were selected due to their stability in alkaline media: oxides with ilmenite and spinel structures (NiMnO₃ and Ni_1.5Mn_1.5O₄); hydroxides with layered structures (β-Ni_1/2Mn_1/2(OH)₂); and phosphates with olivine and maricite structures (LiNi_1/2Mn_1/2PO₄ and NaNi_1/2Mn_1/2PO₄). In the mixed hydroxides and phosphates, Ni²⁺ and Mn²⁺ ions randomly occupied one crystallographic site, whereas in the ilmenite oxide, a common face was shared by the Ni²⁺ and Mn⁴⁺ ions. The electrochemical parameters of the Ni–Mn compositions were evaluated in asymmetric hybrid supercapacitor cells working with alkaline electrolytes and activated carbon as a negative electrode. A comparative analysis of oxides, hydroxides and phosphates enabled us to differentiate the effects of nickel and manganese ions, structures and morphologies on their capacitive performance. Thus, the best performed electrode was predicted. The electrode composition should simultaneously contain Ni and Mn ions, and their morphologies should comprise spherical aggregates. This was an ilmenite NiMnO₃, which delivers high energy and power density (i.e., 65 W h kg⁻¹ at 3200 W kg⁻¹) and exhibits a good cycling stability (i.e., around 96% after 5000 cycles at a current load of 240 mA g⁻¹). Full article

(This article belongs to the Topic Materials for Energy Harvesting and Storage)

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11 pages, 24607 KiB

Open AccessArticle

Effect of Surface Modification for Carbon Cathode Materials on Charge–Discharge Performance of Li-Air Batteries

by Kaito Fukushima, So Yoon Lee, Kenichi Tanaka, Kodai Sasaki and Takahiro Ishizaki

Materials 2022, 15(9), 3270; https://doi.org/10.3390/ma15093270 - 02 May 2022

Cited by 2 | Viewed by 1672

Abstract

Li-air batteries have attracted considerable attention as rechargeable secondary batteries with a high theoretical energy density of 11,400 kWh/g. However, the commercial application of Li-air batteries is hindered by issues such as low energy efficiency and a short lifetime (cycle numbers). To overcome [...] Read more.

Li-air batteries have attracted considerable attention as rechargeable secondary batteries with a high theoretical energy density of 11,400 kWh/g. However, the commercial application of Li-air batteries is hindered by issues such as low energy efficiency and a short lifetime (cycle numbers). To overcome these issues, it is important to select appropriate cathode materials that facilitate high battery performance. Carbon materials are expected to be ideal materials for cathodes due to their high electrical conductivity and porosity. The physicochemical properties of carbon materials are known to affect the performance of Li-air batteries because the redox reaction of oxygen, which is an important reaction for determining the performance of Li-air batteries, occurs on the carbon materials. In this study, we evaluated the effect of the surface modification of carbon cathode materials on the charge–discharge performance of Li-air batteries using commercial Ketjenblack (KB) and KB subjected to vacuum ultraviolet (VUV) irradiation as cathodes. The surface wettability of KB changed from hydrophobic to hydrophilic as a result of the VUV irradiation. The ratio of COOH and OH groups on the KB surface increased after VUV irradiation. Raman spectra demonstrated that no structural change in the KB before and after VUV irradiation was observed. The charge and discharge capacities of a Li-air battery using VUV-irradiated KB as the cathode decreased compared to original KB, whereas the cycling performance of the Li-air battery improved considerably. The sizes and shapes of the discharge products formed on the cathodes changed considerably due to the VUV irradiation. The difference in the cycling performance of the Li-air battery was discussed from the viewpoint of the chemical properties of KB and VUV-irradiated KB. Full article

(This article belongs to the Topic Materials for Energy Harvesting and Storage)

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