Review
Chemistry, Physical
Yue Zhao, Huilian Hao, Tianliang Song, Xu Wang, Changwang Li, Wenyao Li
Summary: Supercapacitors have gained attention due to their long cycle stability, fast charge-discharge performance, and high-power density. This review summarizes the synthetic strategies and research progress of MnO2-graphene-based multi-element composites, including their combination with various carbon materials, transition metal oxides, and conducting polymers. The possible development directions of MnO2-graphene-based composite electrode materials in the future are also discussed.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Engineering, Environmental
Andrew J. Sellathurai, Sreemannarayana Mypati, Marianna Kontopoulou, Dominik P. J. Barz
Summary: This study successfully achieved the preparation of highly concentrated graphene nanoplatelet dispersions by using graphene oxide as a dispersing agent in the liquid phase exfoliation process. The factors affecting the exfoliation process, such as the concentration of graphene oxide, size of graphite sheets, viscosity of the dispersion, etc., were investigated. Additionally, the exfoliated graphene dispersions were used to synthesize graphene hydrogel electrode materials, demonstrating good capacitance performance and cycling stability.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Energy & Fuels
Taegun Kim, Edmund Samuel, Jaewoo Seol, Hae-Seok Lee, Sam S. Yoon
Summary: A water-based iron oxide/cobalt/reduced graphene oxide (Fe2O3/Co/rGO) precursor was spray-coated onto a flexible substrate using supersonic spraying to fabricate supercapacitor electrodes with enhanced energy storage capability. The inclusion of cobalt in iron oxide increased the number of electrochemical reaction sites and improved local electron mobility. The use of supersonic spraying resulted in a uniform coating of reduced graphene oxide and increased electron mobility in the electrode. Additionally, the exfoliation of graphene oxide sheets during spraying increased surface area and enhanced the adherence of cobalt ferrite particles to the substrate, facilitating electron transport throughout the electrode.
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2022)
Article
Chemistry, Physical
C. Justin Raj, Ramu Manikandan, Pugalenthiyar Thondaiman, Periyasamy Sivakumar, A. Dennyson Savariraj, Won-Je Cho, Byung Chul Kim, Hyun Jung
Summary: Graphene synthesized via electrochemical exfoliation of graphite is a simple, fast, and scalable technique suitable for supercapacitor electrodes. Pulse sonication assisted electrochemical exfoliation significantly enhances the process, with the nature of electrolyte and intercalation ions playing a crucial role in the quality and performance of graphene. The presence of various defect sites on the surface and edges of graphene exfoliated in acidic and neutral electrolytes contributes to improved electrochemical performance.
Article
Chemistry, Applied
Han-Wei Chang, Yu-Cheng Huang, Jeng-Lung Chen, Chi-Liang Chen, Jin-Ming Chen, Da-Hua Wei, Wu-Ching Chou, Chung-Li Dong, Yu-Chen Tsai
Summary: Electrochemistry and X-ray absorption spectroscopy (XAS) were used to evaluate the capacitive performance and electronic structure of MnO2/reduced graphene oxide (RGO) as a supercapacitor. The specific capacitance of MnO2/RGO increased with the growth time, and the contributions to the capacitance were from electrochemical double-layer capacitance and pseudocapacitance.
Article
Chemistry, Physical
Xianglu Yin, Aijun Teng, Zehua Zeng, Hong Meng, Wei Wu
Summary: This study presents a facile and scalable technology for preparing 2D-MoS2/GO composite without any additives. By exfoliating bulk MoS2 in GO aqueous dispersion under high shear force, the amphiphilic GO nanosheets play a vital role in the exfoliation of MoS2 and preventing its agglomeration. The optimized exfoliation conditions yield 2D-MoS2 nanosheets with desirable dimensions, which are uniformly dispersed in water. The resulting 2D-MoS2/GO film exhibits exceptional volume specific capacitance and cycle stability in supercapacitors.
Article
Chemistry, Physical
Mi He, Linli Cao, Weilong Li, Xinwei Chang, Zhaoyu Ren
Summary: A hierarchical alpha-MnO2 nanotube@delta-MnO2 nanoflake structure was successfully fabricated on 3D graphene foam as a lightweight and free-standing electrode for supercapacitors. The composite electrode exhibited excellent electrochemical performance, with a maximum specific capacitance achieved at 60% MnO2 mass percentage. An asymmetric supercapacitor based on the GF@MNT@MNF composites showed a great energy density under a wide potential range.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Energy & Fuels
Hani Sayahi, Zahra Mehrvar, Farshid Mohsenzadeh, Hossein Reza Darabi, Kioumars Aghapoor, Hossein Taherzadeh
Summary: A novel, facile and economical method of electrochemical exfoliation is used to fabricate graphene structures with excellent specific capacitance and electrochemical performance. The prepared graphene exhibits remarkable EDLC performances, making it promising for industrial applications.
JOURNAL OF ENERGY STORAGE
(2023)
Article
Chemistry, Multidisciplinary
Gu Liu, Jian Liu, Kejun Xu, Liuying Wang, Shanxin Xiong
Summary: A quick and convenient method was presented to prepare graphene paper as a flexible current collector, combined with MnO2 to obtain a flexible supercapacitor composite electrode without using binder or conductive agent. The electrochemical performance was significantly improved, showing high specific capacitance.
Article
Chemistry, Physical
Yang Zhou, Xinying Cheng, Feng Huang, Zhao Sha, Zhaojun Han, Junyan Chen, Wenmu Yang, Yuyan Yu, Jin Zhang, Shuhua Peng, Shuying Wu, Andrew Rider, Liming Dai, Chun H. Wang
Summary: A new approach to create hierarchically structured electrodes for supercapacitors allows them to retain capacity under mechanical deformation, enabling the fabrication of high-performance moldable energy storage devices for wearable electronics and wireless electronic skins.
Article
Chemistry, Physical
Ramu Banavath, Siva Sankar Nemala, Soo-Hyun Kim, Sivasambu Bohm, Mohd Zahid Ansari, Debananda Mohapatra, Parag Bhargava
Summary: Graphene-based materials show great potential for multidimensional energy storage capability. Large-scale production of high-quality Graphene Nanoplatelets through high-pressure spray exfoliation method is effective in developing high-performance supercapacitors.
Article
Materials Science, Multidisciplinary
T. M. W. J. Bandara, T. M. A. A. B. Thennakoon, G. G. D. M. G. Gamachchi, L. R. A. K. Bandara, B. M. K. Pemasiri, U. Dahanayake
Summary: This study focuses on a low-cost and nonoxidative approach to exfoliating vein graphite into graphene. The combination of electrochemical exfoliation and ultrasonic vibration with inexpensive black tea solution as a substitute for toxic solvents proves to be successful in producing high-quality graphene. The study reveals the potential for large-scale production of graphene using this method.
MATERIALS CHEMISTRY AND PHYSICS
(2022)
Article
Chemistry, Physical
Yichen Wang, Bingquan Hu, Jing Luo, Yao Gu, Xiaoya Liu
Summary: In this study, a facile method was developed to construct polyaniline@MnO2/graphene ternary hybrid hollow spheres via Pickering emulsion polymerization. The PANI@MnO2/GR HS exhibited significantly improved electrochemical performance with a maximum specific capacitance of 743.8 F g(-1) and good cycling stability, retaining 93% of the initial value after 2000 cycles.
ACS APPLIED ENERGY MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
V. J. Mane, S. B. Kale, S. B. Ubale, V. C. Lokhande, C. D. Lokhande
Summary: This study prepared Ag-doped MnO2/GO composite thin films using the SILAR method, which exhibited high specific surface area and excellent electro-chemical performance with a maximum specific capacitance of 877 F g(-1) and capacity retention of 94.57% in the electrolyte. The flexible solid state symmetric supercapacitor device showed good cycling stability and electro-chemical performance with a specific capacitance of 164 F g(-1) and capacitive retention of 94% after 10,000 cycles.
MATERIALS TODAY CHEMISTRY
(2021)
Article
Chemistry, Analytical
Bengu Getiren, Hasan Altinisik, Furkan Soysal, Zafer Ciplak, Nuray Yildiz
Summary: In this study, a ternary nanocomposite of N-rGO-MnO20.5-PANI6 was synthesized for the first time through a simple approach. This nanocomposite exhibited high capacitance (405.2 F/g), excellent rate capability (96.6% capacitance retention at 5 A/g), long cycle stability (86.1% capacitance retention after 5000 cycles), and high energy and power density (13.9 Wh/kg and 260.6 W/kg at 1 A/g). Therefore, this ternary nanocomposite shows great potential as an electrode material for supercapacitor applications.
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
(2023)
Article
Chemistry, Physical
J. Zamora, T. Bautista, N. S. Portillo-Velez, A. Reyes-Montero, H. Pfeiffer, F. Sanchez-Ochoa, H. A. Lara-Garcia
Summary: Experimental and DFT studies were conducted on the structural, magnetic, and optical properties of RFeO3 perovskites. The perovskites exhibited an orthorhombic crystal structure and weak ferromagnetic behavior. They were confirmed to be semiconductors with a bandgap of approximately 2.1 eV.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Xianxiang Lv, Jing Jin, Weiguang Yang
Summary: By depositing TiN and TiO2 surface layers on AlSi films, the electrochemical performance of silicon-based anodes can be significantly improved, suppressing volume expansion and promoting the formation of a stable SEI layer.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Sharafat Ali, Haider Ali, Syedul Hasnain Bakhtiar, Sajjad Ali, Muhammad Zahid, Ahmed Ismail, Pir Muhammad Ismail, Amir Zada, Imran Khan, Huahai Shen, Rizwan Ullah, Habib Khan, Mohamed Bououdina, Xiaoqiang Wu, Fazal Raziq, Liang Qiao
Summary: The construction and optimization of redox-heterojunctions using a bifunctional phosphate as an electron-bridge demonstrated significant improvements in photo catalytic activity, including enhanced dispersion, reduced interfacial migration resistance, and increased abundance of active-sites.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Ren-Ni Luan, Na Xu, Chao-Ran Li, Zhi-Jie Zhang, Yu-Sheng Zhang, Jun Nan, Shu-Tao Wang, Yong-Ming Chai, Bin Dong
Summary: Extensive research has revealed that oxygen evolution reaction (OER) in alkaline conditions involves dynamic surface restructuring. The development and design of sulfide/oxide pre-catalysts can reasonably adjust the composition and structure after surface reconstruction, which is crucial for OER. This study utilized a simple two-step hydrothermal method to achieve in situ S leaching and doping, inducing the composition change and structure reconstruction of CoFe oxides. The transformed FeOOH and CoOOH exhibited excellent OER activity and could be easily mass-produced using low-cost iron based materials and simple methods.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Jun'an Lai, Daofu Wu, Peng He, Kang An, Yijia Wang, Peng Feng, WeiWei Chen, Zixian Wang, Linfeng Guo, Xiaosheng Tang
Summary: Zero-dimensional organic-inorganic metal halides (OMHs) are gaining attention in the fabrication of light-emitting diodes due to their broad emission band and high photoluminescence quantum yield. This work synthesized a zero-dimensional organic tetraphenylphosphonium bismuth chloride (TBC) that showed efficient blue light emission, with the emission mechanism attributed to the transition of Bi3+ ions. White light-emitting diodes (WLEDs) were fabricated using TBC, along with green-emitting and red-emitting single crystals, achieving single-component white emissions. These findings demonstrate the different emission mechanism of ns2 ions-based OMHs and highlight the potential of bismuth-based OMHs in WLEDs applications.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Xuewei Liang, Yunhai Su, Taisen Yang, Zhiyong Dai, Yingdi Wang, Xingping Yong
Summary: The revolutionary design concept of high-entropy alloys has brought new opportunities and challenges to the development of advanced metal materials. In this work, AlCrCuFe2NiTix high-entropy flux cored wires were prepared by combining the design idea of a high-entropy alloy with the characteristics of flux cored wire. AlCr-CuFe2NiTix high-entropy surfacing alloys were prepared using gas metal arc welding technology. The wear properties of the alloys were analyzed, and the phase composition, microstructure, strengthening mechanism, and wear mechanism were discussed. The results show that the alloys exhibit a dendritic microstructure with BCC/B2 + FCC phases. Increasing Ti content leads to the precipitation of Laves phase. The alloys show improved microhardness and wear resistance due to the precipitation of coherent B2 and Laves phases. However, excessive Ti addition results in the increase of Laves phase and reduced wear resistance of the alloys.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
M. Vadivel, M. Senthil Pandian, P. Ramasamy, Qiang Jing, Bo Liu
Summary: This work presents the enhanced photocatalytic and electrochemical performance of g-C3N4 assisted PAA on CoFe2O4 ternary nanocomposites. The incorporation of PAA and g-C3N4 improves the separation efficiency of photogenerated charge carriers, resulting in superior photocatalytic degradation and high specific capacitance values.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Vibhu T. Sivanandan, Ramany Revathy, Arun S. Prasad
Summary: In this study, pure and doped cobalt ferrite nanoparticles were prepared using the sol-gel auto-combustion method with the aid of lemon juice as eco-fuel. The crystal structure, lattice parameter, crystallite size, microstrain, optical parameters, and room temperature magnetic properties of the samples were analyzed. The effect of doping on the magnetic properties was also investigated.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Qing Guo, Bowen Zhang, Benzhe Sun, Yang Qi
Summary: This study prepared ZnO films with various nonpolar preferred orientations using conventional chemical bath deposition method and characterized their growth process and mechanism. It was found that the type and concentration of nitrate could control the preferred orientation and surface roughness of ZnO films. Additionally, ZnO films with different preferred orientations exhibited different optical properties.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Chong Zhang, Yan Liu, Zhaoyan Wang, Hang Yang
Summary: In this study, six bimetallic FeCo particles were synthesized via the hydrothermal method at different Fe:Co ratios. The Fe:Co ratio not only modulates the composition of the particles but also influences their structure and magnetic properties. The FeCo alloys showed a transformation from an Fe-based structure to a Co-based structure with increasing Co content. The Fe:Co ratio of 1:1 and 3:1 resulted in particles with the highest and lowest saturation magnetization, respectively.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Jianning Zhang, Jing Li, Yiren Wang, Xiaodong Mao, Yong Jiang
Summary: We conducted a study on the formation of ultra-fine Y-Ti-Ta-O nano-oxides in Ta+B micro-alloyed 13CrWTi-ODS alloys using electron microscopy and first-principles calculations. The Y-Ti-Ta-O nano-oxides were found to be mainly Y2(Ti,Ta)2O7, with an average size of 7 nm and a number density of 6.8 x 1023 m-3. Excess boron was found to enhance the adhesion of some low-sigma grain boundaries but weaken the Fe/Y2Ti2O7 interface, while excess tantalum enhanced the Fe/Y2Ti2O7 interface but caused serious degradation of grain boundaries.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Yirong Fang, Pei Cheng, Hang Yuan, Hao Zhao, Lishu Zhang
Summary: A new composite system of nitrogen-doped reduced graphene oxide and black phosphorus quantum dots has been developed for tumor therapy, showing improved electrochemical properties and stability. The system generates hydrogen peroxide and hydroxyl radical to effectively kill tumor cells.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Xiufang Qin, Yuanli Ma, Hui Zhang, Ting Zhang, Fang Wang, Xiaohong Xu
Summary: The structure and magnetism of cobalt ferrites after Mn2+-Tb3+ co-doping were studied. Co-doped samples exhibited cubic spinel structure and spherical shape of ferrite nanoparticles. The redistribution of Co2+ and Fe3+ ions between octahedral and tetrahedral sites was observed due to Mn2+-Tb3+ co-doping. The coercivity and magnetization saturation of co-doped samples were significantly improved, leading to a maximum energy product that is 190% higher than that of the un-doped sample.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Ho Yeon Lee, Wonjong Yu, Yoon Ho Lee
Summary: Recently, there has been an increasing interest in developing ultra-fine nanostructured electrodes with extensive reaction areas to enhance the performance and low-temperature operation of solid oxide fuel cells. The use of a refined approach involving co-sputtering metal alloys and oxide targets has demonstrated the feasibility of nano-columnar structures in perovskite-based electrodes, expanding the temperature range of thin film electrodes. This study systematically examines the effects of chamber pressure control in the co-sputtering process and identifies the intricate relationship between sputtering pressure and film structure. By fine-tuning the columnar growth in the electrode, significant improvements in performance and thermo-mechanical properties were achieved, resulting in high-performance all-sputtered solid oxide fuel cells.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Qianyun Bai, Xiaoxiao Yan, Da Liu, Kang Xiang, Xin Tu, Yanhui Guo, Renbing Wu
Summary: This study proposes a simple method to develop a non-precious transition metal-based electrocatalyst with high catalytic activity and robustness for the hydrogen evolution reaction. The as-synthesized electrode exhibits a low overpotential and high current density, indicating its potential in energy conversion.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)