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Metallic glass roadmap

Metallic glass roadmap
Abstract:

Metallic glasses that mainly make up of metallic elements are new family member of glassy materials. This new kind of glass combines the characters of liquids and solids, glasses and metals, making it fascinating to both scientists and industrialists. With the discovery of more and more systems, metallic glass is becoming one of the most active research field in metallic materials, and some concepts and technology derived from metallic glasses also facilitate the development of other materials from quasi-crystals to high entropy alloys. Metallic glasses have now been successfully used in aerospace, robotics, medicine and consumer electronics etc., and the real applications of metallic glasses are still growing. On the other hand, the diverse properties and the unique structural of the metallic glasses render them ideal models to study major open issues including structural model of disordered materials, glass transition, collective motion and energy landscape etc. However, the understanding the emerging properties and phenomena of metallic glasses still poses enormous challenges, which have stimulated a wealth of new experimental approaches, the synthesis of new systems with tailored properties, novel experimental techniques and theoretical and numerical methods. In this Roadmap, we try to provide a broad overview of recent and possible future activities in the metallic glass field, and present a roadmap to future development and applications of metallic glasses by gathering contributions with different backgrounds, illustrating the major challenges and discussing the latest technology and strategy to tackle these challenges with experts covering various developments and challenges in general concepts, synthesis and characterisation, and simulation and theoretical methods.

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Amorphous/Crystalline Heterostructured Nanoporous High-Entropy Metallic Glasses for Efficient Water Splitting
Amorphous/Crystalline Heterostructured Nanoporous High-Entropy Metallic Glasses for Efficient Water Splitting
Abstract:
Developing nanoporous high-entropy metallic glass (HEMG) with a high specific surface area presents a promising approach to develop a cost-effective and efficient catalyst, which utilize the synergistic effect of its multi-component composition and the adjustable atomic environment of its disordered structure. However, the glassy structure invariably gets erased due to the inevitable crystallization during the nanoporous construction procedure through dealloying. Here, an innovative HEMG with an endogenetic nano-scale phase-separated structure is specially designed to maintain a fully glassy state throughout the nanoporous construction procedure. Consequently, an amorphous/crystalline heterostructure (ACH)—nanocrystal flakes embedded in amorphous ligaments—is intentionally constructed, which exhibits significant lattice distortion at amorphous/crystalline interfaces, resulting in high density of active sites. The ACH facilitates intermediate adsorption by promoting directional charge transfer between amorphous and crystalline phases and improves product desorption through downshifting the d-band center. This results in remarkable electrolysis performance, requiring only a 1.53 V potential to achieve a current density of 10 mA cm-2 for overall water-splitting in an alkaline electrolyte, surpassing that of commercial Pt/C || IrO2 catalysts of 1.62 V. This research pioneers strategies to refine the composition, atomic structure, and electron characteristics of HEMG, unlocking new functional applications.
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Heterojunction catalysts for urea oxidation reaction

Heterojunction catalysts for urea oxidation reaction
Abstract:

The electrocatalytic urea oxidation reaction (UOR) is a promising strategy for addressing both environmental remediation and energy conversion challenges. Recently, heterojunction catalysts have gained significant attention due to their enhanced catalytic activity and stability. This review provides a comprehensive analysis of recent advancements in heterojunction catalysts for UOR. We begin by outlining the fundamental principles of UOR and key catalyst evaluation parameters. Next, we discuss the unique features of heterojunction catalysts, highlighting their structural and electronic advantages. The applications of various heterojunction architectures—including those based on transition metals, alloys, metal (hydro)oxides, chalcogenides, pnictides, and metal-organic frameworks (MOFs)—are then examined in detail. A particular focus is placed on structure–performance relationships and rational design strategies to optimize catalytic efficiency. This review offers valuable insights into the development of next-generation heterojunction catalysts for efficient and sustainable UOR applications.

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Downconversion Mechanoluminescence from Lanthanide Codoped Heterojunctions
Abstract:
During the downconversion process, a high-energy photon undergoes conversion into several low-energy photons, leading to enhanced luminous efficiency in both photoluminescent and electroluminescent devices. This phenomenon has been applied in various fields, including solar cells, plasma display panels, and green lighting technologies such as mercury-free fluorescent lamps. However, the concept of downconversion (quantum cutting) has not been fully explored in the context of mechanoluminescent materials. In this study, we successfully synthesized a heterojunction of CaF2/CaZnOS exhibiting efficient downconversion mechanoluminescence (ML) properties. By controlling the CaF2 to CaZnOS ratio and incorporating Tb3+ doping, we obtained a highly effective heterojunction structure that significantly enhanced ML. Moreover, we extended this material to several commonly utilized downconversion ion-doping combinations, achieving enhanced ML for Tb3+, Pr3+, and Yb3+ single ions. For the first time, we demonstrate the downconversion (quantum cutting) ML of Tb3+–Yb3+ and Pr3+–Yb3+ pairs within heterojunction microstructures. This study presents the design and synthesis of a novel heterojunction material capable of realizing downconversion ML, which holds promise for future applications in diverse fields.
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Excellent mechanical properties from the synergy of carbon partitioning, L12-nano-precipitation and TRIP effects in Fe-Ni-Al-Ti-C steel
Excellent mechanical properties from the synergy of carbon partitioning, L12-nano-precipitation and TRIP effects in Fe-Ni-Al-Ti-C steel
Abstract:
Multiple strategies and technological pathways exist in developing new advanced high strength steels (AHSSs). For plain carbon steels, carbon partitioning has been utilized to generate a mixture of ferrite/martensite and retained austenite, whereas higher carbon content will stabilize austenite phase. The austenite can be metastable, which can trigger phase transition under stress, so called phase-transformation-induced plasticity (TRIP). For highly alloyed steels with Ni, Al, Ti or other elements, precipitates of the body-centered cubic (BCC), hexagonal close-packed (HCP), L21, L12 types can form during aging/partitioning. L12 phase shows exceptional deformation capability because itself can sustain significant plastic deformation. Motivated by these two design strategies, this work started from a Fe-Ni alloy by added with appropriate amounts of Al, Ti, and C to obtain a series of Fe-Ni-Al-Ti-C steels by melting, cold rolling and a simple heat treatment (recrystallization and aging/partitioning) history. Microstructural observation and mechanical property testing reveal that the Fe-Ni-Al-Ti-C steels successfully achieves: (1) nanosized and densely populated L12 precipitates in both ferrite and austenite phases, (2) enhanced stability of austenitic phase with TRIP capability, (3) ultrafine-grained microstructure due to precipitate-retarded ferrite grain growth, and (4) extra dislocation storage of precipitate-cutting dislocation loops. The synergy of all these factors results into tensile strengths of 1.2-1.8 GPa and uniform ductility of 10-30%, which is comparable to twining-induced plasticity steels.
Recrystallization induced by heat treatment regulates the anisotropic behavior of CoCrMo alloys fabricated by laser powder bed fusion
Lijin Dai, Changhui Song, Houxiong Fu, Hongyi Chen, Zhongwei Yan, Zibin Liu, Renyao Li, Anming Wang, Yongqiang Yang, Jia-Kuo Yu
2025, 4(2): 025001. DOI: 10.1088/2752-5724/adb50a
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Vacancy-engineered LiMn2O4 embedded in dual-heteroatom-doped carbon via metal-organic framework-mediated synthesis towards longevous lithium ion battery
Xiaoming Lin, Jia Lin, Xiaomeng Lu, Xiaohong Tan, Hao Li, Wanxin Mai, Yuhong Luo, Yongbo Wu, Shuangqiang Chen, Chao Yang, Yong Wang Show full author list
2025, 4(2): 025101. DOI: 10.1088/2752-5724/ad9e08
Abstract PDF
Redefining electrolyte efficiency: bridging the gap with a systematic samarium–copper co-doping approach for optimized conductivity in advanced semiconductor ionic fuel cell
Muhammad Shahid Sharif, Zuhra Tayyab, Sajid Rauf, Muhammad Ahsan Masood, MAK Yousaf Shah, Muhammad Tayyab, Abdullah N Alodhayb, Bin Zhu
2025, 4(2): 025102. DOI: 10.1088/2752-5724/adbcc9
Abstract PDF
Lead (II) fluoride additive modulating grains growth of water-processed metal halide perovskites for enhanced efficiency in solar cells
Minh Tam Hoang, Junxian Liu, Yang Yang, Maciej Klein, Wei-Hsun Chiu, Yongyue Yu, Ngoc Duy Pham, Paul Moonie, Ajay Pandey, Liangzhi Kou, Hongxia Wang Show full author list
2025, 4(2): 025103. DOI: 10.1088/2752-5724/adc8c0
Abstract PDF
Ag management of rudorffites solar cells utilizing aliphatic ammonium
Xinyu Guo, Wenjin Yu, Xiangdong Li, Hantao Wang, Qinyun Liu, Yu Zou, Yunan Gao, Zhijian Chen, Lixin Xiao, Bo Qu
2025, 4(2): 025104. DOI: 10.1088/2752-5724/adcbc7
Abstract PDF
Exciton funneling in 2D artificial potential landscapes decorated by reassembled micro-bubbles
Wenqi Qian, Haiyi Liu, Guangyi Tao, Fangxun Liu, Sihan Lin, Tengteng Gao, Xueying Wang, Qihong Hu, Dalin Zhang, Dong Xiang, Lie Lin, Pengfei Qi, Zheyu Fang, Weiwei Liu Show full author list
2025, 4(2): 025301. DOI: 10.1088/2752-5724/adc8c1
Abstract PDF
MOF-MoS2 nanosheets doped PEDOT: PSS for organic electrochemical transistors in enhanced glucose sensing and machine learning-based concentration prediction
Yali Sun, Yun Li, Yang Zhou, Ting Cai, Yuxuan Chen, Chao Zou, Han Song, Shenghuang Lin, Shenghua Liu
2025, 4(2): 025302. DOI: 10.1088/2752-5724/adccdf
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An integrated hybrid 3D bioprinting of heterogeneous and zone-specific construct resembling structural and biofunctional properties of osteochondral tissue
Yaxin Wang, Yanhao Hou, Cian Vyas, Boyang Huang, Paulo Bartolo
2025, 4(2): 025401. DOI: 10.1088/2752-5724/adb7f6
Abstract PDF
Breathable core-shell microneedle patches for diabetic wound treatment
Lu Fan, Yu Wang, Li Wang, Xiang Lin, Xiaoju Wang, Luoran Shang, Hongbo Zhang, Yuanjin Zhao
2025, 4(2): 025402. DOI: 10.1088/2752-5724/adcbc6
Abstract PDF
A general protocol for phosphorescent platinum(II) complexes: generation, high throughput virtual screening and highly accurate predictions
Shuai Wang, ChiYung Yam, LiHong Hu, Faan-Fung Hung, Shuguang Chen, Chi-Ming Che, GuanHua Chen
2025, 4(2): 025601. DOI: 10.1088/2752-5724/adb320
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Taking advantage of glass: capturing and retaining the helium gas on the moon
Abstract:
Helium-3 (3He) is a noble gas that has critical applications in scientific research and promising application potential as clean fusion energy. It is thought that the lunar regolith contains large amounts of helium, but it is challenging to extract because most helium atoms are reserved in defects of crystals or as solid solutions. Here, we find large amounts of helium bubbles in the glassy surface layer of ilmenite particles that were brought back by the Chang’E-5 mission. The special disordered atomic packing structure of glasses should be the critical factor for capturing the noble helium gas. The reserves in bubbles do not require heating to high temperatures to be extracted. Mechanical methods at ambient temperatures can easily break the bubbles. Our results provide insights into the mechanism of helium gathering on the moon and offer guidance on future in situ extraction.
Topical Review •
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Advantages and challenges of self-assembled monolayer as a hole-selective contact for perovskite solar cells
Abstract:
Charge-transporting layers (CTLs) are important in determining the performance and stability of perovskite solar cells (PSCs). Recently, there has been considerable use of self-assembled monolayers (SAMs) as charge-selective contacts, especially for hole-selective SAMs in inverted PSCs as well as perovskite involving tandem solar cells. The SAM-based charge-selective contact shows many advantages over traditional thin-film organic/inorganic CTLs, including reduced cost, low optical and electric loss, conformal coating on a rough substrate, simple deposition on a large-area substrate and easy modulation of energy levels, molecular dipoles and surface properties. The incorporation of various hole-selective SAMs has resulted in high-efficiency single junction and tandem solar cells. This topical review summarizes both the advantages and challenges of SAM-based charge-selective contacts, and discusses the potential direction for future studies.
Topical Review •
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Multiscale understanding of high-energy cathodes in solid-state batteries: from atomic scale to macroscopic scale
Abstract:
In the crucial area of sustainable energy storage, solid-state batteries (SSBs) with nonflammable solid electrolytes stand out due to their potential benefits of enhanced safety, energy density, and cycle life. However, the complexity within the composite cathode determines that fabricating an ideal electrode needs to link chemistry (atomic scale), materials (microscopic/mesoscopic scale), and electrode system (macroscopic scale). Therefore, understanding solid-state composite cathodes covering multiple scales is of vital importance for the development of practical SSBs. In this review, the challenges and basic knowledge of composite cathodes from the atomic scale to the macroscopic scale in SSBs are outlined with a special focus on the interfacial structure, charge transport, and mechanical degradation. Based on these dilemmas, emerging strategies to design a high-performance composite cathode and advanced characterization techniques are summarized. Moreover, future perspectives toward composite cathodes are discussed, aiming to facilitate the develop energy-dense SSBs.
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The role of grain boundaries in solid-state Li-metal batteries
Abstract:
Despite the potential advantages promised by solid-state batteries, the success of solid-state electrolytes has not yet been fully realised. This is due in part to the lower ionic conductivity of solid electrolytes. In many solid superionic conductors, grain boundaries are found to be ionically resistive and hence contribute to this lower ionic conductivity. Additionally, in spite of the hope that solid electrolytes would inhibit lithium filaments, in most scenarios their growth is still observed, and in some polycrystalline systems this is suggested to occur along grain boundaries. It is apparent that grain boundaries affect the performance of solid-state electrolytes, however a deeper understanding is lacking. In this perspective, the current theories relating to grain boundaries in solid-state electrolytes are explored, as well as addressing some of the challenges which arise when trying to investigate their role. Glasses are presented as a possible solution to reduce the effect of grain boundaries in electrolytes. Future research directions are suggested which will aid in both understanding the role of grain boundaries, and diminishing their contribution in cases where they are detrimental.
Topical Review •
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Deep potentials for materials science
Abstract:
To fill the gap between accurate (and expensive) ab initio calculations and efficient atomistic simulations based on empirical interatomic potentials, a new class of descriptions of atomic interactions has emerged and been widely applied; i.e. machine learning potentials (MLPs). One recently developed type of MLP is the deep potential (DP) method. In this review, we provide an introduction to DP methods in computational materials science. The theory underlying the DP method is presented along with a step-by-step introduction to their development and use. We also review materials applications of DPs in a wide range of materials systems. The DP Library provides a platform for the development of DPs and a database of extant DPs. We discuss the accuracy and efficiency of DPs compared with ab initio methods and empirical potentials.
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The interplay between (electro)chemical and (chemo)mechanical effects in the cycling performance of thiophosphate-based solid-state batteries
Abstract:
Solid-state batteries (SSBs) are a promising next step in electrochemical energy storage but are plagued by a number of problems. In this study, we demonstrate the recurring issue of mechanical degradation because of volume changes in layered Ni-rich oxide cathode materials in thiophosphate-based SSBs. Specifically, we explore superionic solid electrolytes (SEs) of different crystallinity, namely glassy 1.5Li2S-0.5P2S5-LiI and argyrodite Li6PS5Cl, with emphasis on how they affect the cyclability of slurry-cast cathodes with NCM622 (60% Ni) or NCM851005 (85% Ni). The application of a combination of ex situ and in situ analytical techniques helped to reveal the benefits of using a SE with a low Young’s modulus. Through a synergistic interplay of (electro)chemical and (chemo)mechanical effects, the glassy SE employed in this work was able to achieve robust and stable interfaces, enabling intimate contact with the cathode material while at the same time mitigating volume changes. Our results emphasize the importance of considering chemical, electrochemical, and mechanical properties to realize long-term cycling performance in high-loading SSBs.
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Efficient red perovskite quantum dot light-emitting diode fabricated by inkjet printing
Abstract:
Perovskite quantum dots (PeQDs) are considered potential display materials due to their high color purity, high photoluminescence quantum yield (PLQY), low cost and easy film casting. In this work, a novel electroluminescence (EL) device consisting of the interface layer of long alkyl-based oleylammonium bromide (OAmBr), which passivates the surface defects of PeQDs and adjusts the carrier transport properties, was designed. The PLQY of the OAmBr/PeQD bilayer was significantly improved. A high-performance EL device with the structure of indium tin oxide/poly(3,4-ethylenedioxythiophene) polystyrene sulfonate/poly(bis(4-phenyl)(2,4,6-trimethylphenyl)amine)/OAmBr/PeQDs/2,2,2-(1,3,5-benzinetriyl)-tris(1-phenyl-1H benzimidazole)/LiF/Al was constructed using a spin-coating method. A peak external quantum efficiency (EQE) of 16.5% at the emission wavelength of 646 nm was obtained. Furthermore, an efficient matrix EL device was fabricated using an inkjet printing method. A high-quality PeQD matrix film was obtained by introducing small amounts of polybutene into the PeQDs to improve the printing process. The EQE reached 9.6% for the matrix device with 120 pixels per inch and the same device structure as that of the spin-coating one.
Topical Review •
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Recent advances and future perspectives for aqueous zinc-ion capacitors
Abstract:
Ion-hybrid capacitors are expected to combine the high specific energy of battery-type materials and the superior specific power of capacitor-type materials and are considered as a promising energy storage technique. In particular, aqueous zinc-ion capacitors (ZIC), possessing the merits of high safety, cost-efficiency and eco-friendliness, have been widely explored with various electrode materials and electrolytes to obtain excellent electrochemical performance. In this review, we first summarize the research progress on enhancing the specific capacitance of capacitor-type materials and review the research on improving the cycling capability of battery-type materials under high current densities. Then, we look back on the effects of electrolyte engineering on the electrochemical performance of ZIC. Finally, we propose research challenges and development directions for ZIC. This review provides guidance for the design and construction of high-performance ZIC.
Topical Review •
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Interface and surface engineering of black phosphorus: a review for optoelectronic and photonic applications
Abstract:
Since being rediscovered as an emerging 2D material, black phosphorus (BP), with an extraordinary energy structure and unusually strong interlayer interactions, offers new opportunities for optoelectronics and photonics. However, due to the thin atomic body and the ease of degradation with water and oxides, BP is highly sensitive to the surrounding environment. Therefore, high-quality engineering of interfaces and surfaces plays an essential role in BP-based applications. In this review, begun with a review of properties of BP, different strategies of interface and surfaces engineering for high ON-OFF ratio, enhanced optical absorption, and fast optical response are reviewed and highlighted, and recent state-of-the-art advances on optoelectronic and photonic devices are demonstrated. Finally, the opportunities and challenges for future BP-related research are considered.
Topical Review •
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Recent development of chemically complex metallic glasses: from accelerated compositional design, additive manufacturing to novel applications
Abstract:
Metallic glasses (MGs) or amorphous alloys are an important engineering material that has a history of research of about 80-90 years. While different fast cooling methods were developed for multi-component MGs between 1960s and 1980s, 1990s witnessed a surge of research interest in the development of bulk metallic glasses (BGMs). Since then, one central theme of research in the metallic-glass community has been compositional design that aims to search for MGs with a better glass forming ability, a larger size and/or more interesting properties, which can hence meet the demands from more important applications. In this review article, we focus on the recent development of chemically complex MGs, such as high entropy MGs, with new tools that were not available or mature yet until recently, such as the state-of-the-art additive manufacturing technologies, high throughput materials design techniques and the methods for big data analyses (e.g. machine learning and artificial intelligence). We also discuss the recent use of MGs in a variety of novel and important applications, from personal healthcare, electric energy transfer to nuclear energy that plays a pivotal role in the battle against global warming.
Topical Review •
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Deep potentials for materials science
Abstract:
To fill the gap between accurate (and expensive) ab initio calculations and efficient atomistic simulations based on empirical interatomic potentials, a new class of descriptions of atomic interactions has emerged and been widely applied; i.e. machine learning potentials (MLPs). One recently developed type of MLP is the deep potential (DP) method. In this review, we provide an introduction to DP methods in computational materials science. The theory underlying the DP method is presented along with a step-by-step introduction to their development and use. We also review materials applications of DPs in a wide range of materials systems. The DP Library provides a platform for the development of DPs and a database of extant DPs. We discuss the accuracy and efficiency of DPs compared with ab initio methods and empirical potentials.
Topical Review •
OPEN ACCESS
Interface and surface engineering of black phosphorus: a review for optoelectronic and photonic applications
Abstract:
Since being rediscovered as an emerging 2D material, black phosphorus (BP), with an extraordinary energy structure and unusually strong interlayer interactions, offers new opportunities for optoelectronics and photonics. However, due to the thin atomic body and the ease of degradation with water and oxides, BP is highly sensitive to the surrounding environment. Therefore, high-quality engineering of interfaces and surfaces plays an essential role in BP-based applications. In this review, begun with a review of properties of BP, different strategies of interface and surfaces engineering for high ON-OFF ratio, enhanced optical absorption, and fast optical response are reviewed and highlighted, and recent state-of-the-art advances on optoelectronic and photonic devices are demonstrated. Finally, the opportunities and challenges for future BP-related research are considered.
Topical Review •
OPEN ACCESS
Advantages and challenges of self-assembled monolayer as a hole-selective contact for perovskite solar cells
Abstract:
Charge-transporting layers (CTLs) are important in determining the performance and stability of perovskite solar cells (PSCs). Recently, there has been considerable use of self-assembled monolayers (SAMs) as charge-selective contacts, especially for hole-selective SAMs in inverted PSCs as well as perovskite involving tandem solar cells. The SAM-based charge-selective contact shows many advantages over traditional thin-film organic/inorganic CTLs, including reduced cost, low optical and electric loss, conformal coating on a rough substrate, simple deposition on a large-area substrate and easy modulation of energy levels, molecular dipoles and surface properties. The incorporation of various hole-selective SAMs has resulted in high-efficiency single junction and tandem solar cells. This topical review summarizes both the advantages and challenges of SAM-based charge-selective contacts, and discusses the potential direction for future studies.
Paper •
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P2-type layered high-entropy oxides as sodium-ion cathode materials
Abstract:
P2-type layered oxides with the general Na-deficient composition NaxTMO2 (x < 1, TM: transition metal) are a promising class of cathode materials for sodium-ion batteries. The open Na+ transport pathways present in the structure lead to low diffusion barriers and enable high charge/discharge rates. However, a phase transition from P2 to O2 structure occurring above 4.2 V and metal dissolution at low potentials upon discharge results in rapid capacity degradation. In this work, we demonstrate the positive effect of configurational entropy on the stability of the crystal structure during battery operation. Three different compositions of layered P2-type oxides were synthesized by solid-state chemistry, Na0.67(Mn0.55Ni0.21Co0.24)O2, Na0.67(Mn0.45Ni0.18Co0.24Ti0.1Mg0.03)O2 and Na0.67(Mn0.45Ni0.18Co0.18Ti0.1Mg0.03Al0.04Fe0.02)O2 with low, medium and high configurational entropy, respectively. The high-entropy cathode material shows lower structural transformation and Mn dissolution upon cycling in a wide voltage range from 1.5 to 4.6 V. Advanced operando techniques and post-mortem analysis were used to probe the underlying reaction mechanism thoroughly. Overall, the high-entropy strategy is a promising route for improving the electrochemical performance of P2 layered oxide cathodes for advanced sodium-ion battery applications.
Topical Review •
OPEN ACCESS
Recent advances and future perspectives for aqueous zinc-ion capacitors
Abstract:
Ion-hybrid capacitors are expected to combine the high specific energy of battery-type materials and the superior specific power of capacitor-type materials and are considered as a promising energy storage technique. In particular, aqueous zinc-ion capacitors (ZIC), possessing the merits of high safety, cost-efficiency and eco-friendliness, have been widely explored with various electrode materials and electrolytes to obtain excellent electrochemical performance. In this review, we first summarize the research progress on enhancing the specific capacitance of capacitor-type materials and review the research on improving the cycling capability of battery-type materials under high current densities. Then, we look back on the effects of electrolyte engineering on the electrochemical performance of ZIC. Finally, we propose research challenges and development directions for ZIC. This review provides guidance for the design and construction of high-performance ZIC.
Paper •
OPEN ACCESS
The interplay between (electro)chemical and (chemo)mechanical effects in the cycling performance of thiophosphate-based solid-state batteries
Abstract:
Solid-state batteries (SSBs) are a promising next step in electrochemical energy storage but are plagued by a number of problems. In this study, we demonstrate the recurring issue of mechanical degradation because of volume changes in layered Ni-rich oxide cathode materials in thiophosphate-based SSBs. Specifically, we explore superionic solid electrolytes (SEs) of different crystallinity, namely glassy 1.5Li2S-0.5P2S5-LiI and argyrodite Li6PS5Cl, with emphasis on how they affect the cyclability of slurry-cast cathodes with NCM622 (60% Ni) or NCM851005 (85% Ni). The application of a combination of ex situ and in situ analytical techniques helped to reveal the benefits of using a SE with a low Young’s modulus. Through a synergistic interplay of (electro)chemical and (chemo)mechanical effects, the glassy SE employed in this work was able to achieve robust and stable interfaces, enabling intimate contact with the cathode material while at the same time mitigating volume changes. Our results emphasize the importance of considering chemical, electrochemical, and mechanical properties to realize long-term cycling performance in high-loading SSBs.
Topical Review •
OPEN ACCESS
Multiscale understanding of high-energy cathodes in solid-state batteries: from atomic scale to macroscopic scale
Abstract:
In the crucial area of sustainable energy storage, solid-state batteries (SSBs) with nonflammable solid electrolytes stand out due to their potential benefits of enhanced safety, energy density, and cycle life. However, the complexity within the composite cathode determines that fabricating an ideal electrode needs to link chemistry (atomic scale), materials (microscopic/mesoscopic scale), and electrode system (macroscopic scale). Therefore, understanding solid-state composite cathodes covering multiple scales is of vital importance for the development of practical SSBs. In this review, the challenges and basic knowledge of composite cathodes from the atomic scale to the macroscopic scale in SSBs are outlined with a special focus on the interfacial structure, charge transport, and mechanical degradation. Based on these dilemmas, emerging strategies to design a high-performance composite cathode and advanced characterization techniques are summarized. Moreover, future perspectives toward composite cathodes are discussed, aiming to facilitate the develop energy-dense SSBs.
Topical Review •
OPEN ACCESS
Concentrated electrolytes for rechargeable lithium metal batteries
Abstract:
Traditional lithium-ion batteries with graphite anodes have gradually been limited by the glass ceiling of energy density. As a result, lithium metal batteries (LMBs), regarded as the ideal alternative, have attracted considerable attention. However, lithium is highly reactive and susceptible to most electrolytes, resulting in poor cycle performance. In addition, lithium grows Li dendrites during charging, adversely affecting the safety of LMBs. Therefore, LMBs are more sensitive to the chemical composition of electrolytes and their relative ratios (concentrations). Recently, concentrated electrolytes have been widely demonstrated to be friendly to lithium metal anodes (LMAs). This review focuses on the progress of concentrated electrolytes in LMBs, including the solvation structure varying with concentration, unique functions in stabilizing the LMA, and their interfacial chemistry with LMA.
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Microstructure and long-term stability of Ni-YSZ anode supported fuel cells: a review
Abstract:
Nickel-yttria stabilized zirconia (Ni-YSZ) cermet is the most commonly used anode in solid oxide fuel cells (SOFCs). The current article provides an insight into parameters which affect cell performance and stability by reviewing and discussing the related publications in this field. Understanding the parameters which affect the microstructure of Ni-YSZ such as grain size (Leng et al 2003 J. Power Sources 117 26-34) and ratio of Ni to YSZ, volume fraction of porosity, pore size and its distribution, tortuosity factor, characteristic pathway diameter and density of triple phase boundaries is the key to designing a fuel cell which shows high electrochemical performance. Lack of stability has been the main barrier to commercialization of SOFC technology. Parameters influencing the degradation of Ni-YSZ supported SOFCs such as Ni migration inside the anode during prolonged operation are discussed. The longest Ni-supported SOFC tests reported so far are examined and the crucial role of chromium poisoning due to interconnects, stack design and operating conditions in degradation of SOFCs is highlighted. The importance of calcination and milling of YSZ to development of porous structures suitable for Ni infiltration is explained and several methods to improve the electrochemical performance and stability of Ni-YSZ anode supported SOFCs are suggested.
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Solid-state electrolytes for safe rechargeable lithium metal batteries: a strategic view
Abstract:
Despite the efforts devoted to the identification of new electrode materials with higher specific capacities and electrolyte additives to mitigate the well-known limitations of current lithium-ion batteries, this technology is believed to have almost reached its energy density limit. It suffers also of a severe safety concern ascribed to the use of flammable liquid-based electrolytes. In this regard, solid-state electrolytes (SSEs) enabling the use of lithium metal as anode in the so-called solid-state lithium metal batteries (SSLMBs) are considered as the most desirable solution to tackle the aforementioned limitations. This emerging technology has rapidly evolved in recent years thanks to the striking advances gained in the domain of electrolyte materials, where SSEs can be classified according to their core chemistry as organic, inorganic, and hybrid/composite electrolytes. This strategic review presents a critical analysis of the design strategies reported in the field of SSEs, summarizing their main advantages and disadvantages, and providing a future perspective toward the rapid development of SSLMB technology.