CERAMICS INTERNATIONAL
·
2024
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IF 5.1
Tengfei Wang,Qing Pang,Boyu Liu,Hongyu Wang
Titanium dioxide (TiO 2 ), once considered a promising material for microwave absorption, still faces significant challenges in achieving broadband absorption performance. To address this issue, herein, a simple approach is reported for successfully introducing defects and crystalline/amorphous heterostructures onto mesoporous TiO 2 (Meso-am-TiO 2-x ). This study demonstrates the superior microwave absorbing properties of Meso-am-TiO 2-x , particularly in the low-frequency range. A reflection loss of up to −25.7 dB is achieved with a thickness of 4.6 mm, and the effective absorption bandwidth (EAB) value extends to 4.32 GHz. The experimental results indicate that the synergistic effects of the high specific surface area of mesoporous TiO 2 , defects-induced conduction loss, defect-induced dipole polarization loss, and interfacial polarization loss between the crystalline and amorphous heterostructures enhance the microwave absorption properties of Meso-am-TiO 2-x . This study provides insights toward developing innovative low-frequency broadband TiO 2 absorbers.
研究领域:
材料科学
·
电磁学
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DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2024
·
IF 15.7
Xiao Chen,Yunmei Du,Yu Yang,Kang Liu,Jinling Zhao,Xiaodan Xia,Lei Wang
ABSTRACT Directional construction of crystalline/amorphous (c/a)-phosphosulfide heterostructures with exceptional intrinsic activity through a facile strategy is challenging. In this study, we synthesized q-CoPS nanorods with a unique c/a-CoPS core-shell heterostructure through the ‘gas-phase phosphorus vulcanization-quenching' treatment. This work also innovatively masters the regulation of the initial quenching temperature to alter the c/a ratio of the CoPS nanorods . Surprisingly, with increasing initial quenching temperature, the area of the amorphous CoPS shell gradually increases. Density functional theory calculations reveal that the Co sites at the c/a-heterointerface, as the difunctional c/a-interface active site, effectively optimize the kinetics of the hydrogen evolution reaction (HER) and hydrazine oxidation reaction (HzOR). As anticipated, q-CoPS/CF requires an overpotential of only 90 mV at a current density of 1000 mA cm –2 for the alkaline HER, which is much lower than that required using the state-of-the-art Pt/C catalyst. Additionally, q-CoPS/CF achieves a current density of 1000 mA cm –2 at only 0.06 V in the HzOR. Overall, this work proposes an efficient strategy for developing a bifunctional electrocatalyst with a unique c/a-heterostructure to address future energy needs.
研究领域:
材料科学
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电化学
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能源材料
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催化
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产品关联
DOI
高影响因子
ChemCatChem
·
2023
·Vol. 15
·期 4
·e202201413
·
IF 4.5
Dandan Zhao,Shaoyang Zhang,Tianyu Guo,Qiang Zhao,Jianping Du,Jinping Li
Graphical Carbon dioxide reduction : The rectangular nanoflakes with crystalline/amorphous phase structures that the square nanoblocks are confined in amorphous nanoflakes efficiently enhance the electrocatalytic conversion of CO 2 to ethylene. The electrocatalytic reduction of CO 2 to high value-added chemicals is one of the effective technologies to achieve the goal of carbon neutralization. However, highly selective production of hydrocarbon via electrochemical conversion of CO 2 still has great challenges. Herein, a unique CuO phase composition is constructed that consists of rectangular nanoflakes possessing crystalline/amorphous structures by the facile strategy. Crystalline CuO square nanoblocks are confined in amorphous nanoflakes and form crystalline/amorphous hybrid phase. The results of electrocatalytic CO 2 reduction demonstrate that this crystalline/amorphous CuO material exhibits superior CO 2 conversion ability with ethylene Faradaic efficiency of 58.3 % at −1.08 V vs. RHE, which is ascribed to nanoflake structures and fast electron transfer on the crystalline/amorphous interfaces because of superior conductivity of amorphous CuO. The present research provides an effective route to reconstruct novel crystalline/amorphous interfaces of CuO for catalysis applications.
研究领域:
材料科学
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环境科学
·
化学工程
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产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2022
·
IF 6.371
Chengcheng Qi,Chongchao Zhang,Ziyin Yang
A novel strategy was reported to improve electrocatalytic activity of NiCo 2 O 4 by doping Fe. It is interesting to find that the doping of Fe induces formation of nanorod composing with crystalline core and thin amorphous shell. The composition, structure and properties of NiCo 2 O 4 are well characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), cyclic voltammetry and amperometric method. The results display that the presence of thin amorphous shell is conducive to accelerating electron transfer rate and exposing more effective active sites, therefore making the sensor based on Fe-doped NiCo 2 O 4 detect glucose in a wide linear range from 0.2 μM to 3.1 mM with a high sensitivity of 3055.7 μA mM −1 cm −2 and a low detection limit of 0.19 μM. This unique crystalline core/amorphous shell-structured NiCo 2 O 4 demonstrates promising potential as an effective electrocatalyst for glucose sensing.
研究领域:
材料科学
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电化学
·
生物传感
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2023
·
IF 9.5
Xinyu Wang,Xu Yu,Shuang Wu,Pinyi He,Fu Qin,Yongkang Yao,Jianliang Bai,Guojun Yuan,Lili Ren
The rational design of highly efficient and stable electrocatalysts for the oxygen evolution reaction (OER) is an urgent need but remains challenging for various sustainable energy systems. How to adjust the atomic structure and electronic structure of the active center is a key bottleneck problem. Accelerating the electron transfer process and the deep self-reconstruction of active sites could be a cost-effective strategy toward electrocatalytic OER catalyst development. Here, a crystalline–amorphous (c–a) coupled Ni3S2/NiPx electrocatalyst self-supported on nickel foam with an intimate interface was developed via a feasible solvothermal-electrochemistry method. The coupling interface of the crystalline structure with high conductivity and amorphous structure with numerous potential active sites could regulate the electronic structure and optimize the adsorption/desorption of O-containing species, ultimately resulting in high OER catalytic performance. The obtained Ni3S2/NiPx/NF presents a low OER overpotential of 265 mV to obtain 10 mA·cm–2 and a small Tafel slope of 51.6 mV·dec–1. Also, the catalyst with the coupled interface exhibited significantly enhanced long-term stability compared to the other two catalysts, with <5% decay in OER activity over 20 h of continuous operation, while that of Ni3S2/NF and NiPx/NF decreased by about 30 and 50%, respectively. This study provides inspiration for other energy conversion reactions in optimizing the performance of catalysts by coupling crystalline–amorphous structures.
研究领域:
材料科学
·
电催化
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Small
·
2024
·
IF 13
Huan Xu,Xiao Sun,Lingtong Ding,Jingjing Liu,Dan Zhang,Minmin Liu,Xiao Wang,Qixian Zhang,Jiujun Zhang
Electrochemical water-electrolysis for hydrogen generation often requires more energy due to the sluggish oxygen evolution reaction (OER). This work introduces a double-layered nanoflower catalyst, NiFe-LDH@S-NiFeO x /NF, featuring a crystalline NiFe-LDH coating on amorphous S-NiFeO x on nickel foam. Strategically integrating a crystalline-amorphous (c-a) heterostructure leverages strain engineering to enhance OER activity with low overpotentials ( η 100 = 220 and η 500 = 245 mV) and stability (135 h at η 100 and 80 h at η 500 ). Theoretical density functional theory (DFT) calculations reveal that the compressive strain can optimize the adsorption of oxygen-containing intermediates to reduce the reaction energy barrier, thus improving the reaction kinetics and performance of OER. Moreover, its phosphated derivative, NiFeP@S-NiFeO x /NF, exhibits high hydrogen evolution reaction (HER) performance ( η 10 = 64 mV, η 100 = 187 mV). An alkaline water-electrolysis cell of NiFeP@S-NiFeO x /NF(−)||NiFe-LDH@S-NiFeO x /NF(+) requires only a cell voltage of 1.77 V at 100 mA cm −2 , demonstrating excellent stability over 110 h (at both 10 and 100 mA cm −2 ). This work highlights the benefits of integrating crystal-amorphous interfaces and strain effects, offering insights into the understanding and optimizing catalytic OER mechanism and advancing water-electrolysis technology.
研究领域:
材料科学
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电催化
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理论计算
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产品关联
DOI
PubMed
高影响因子
CHEMICAL RESEARCH IN CHINESE UNIVERSITIES
·
2023
·Vol. 39
·期 4
·673-679
·
IF 3.1
Wang Teng,Hu Renquan,Wei Hao,Wei Zehui,Yan Meng,Yang Yong
Developing low-cost Ni-based amorphous/crystalline composites with well-defined nanostructures is expected to achieve a highly efficient oxygen evolution reaction(OER) by exposing more active sites and enhancing the electrical conductivity, but it still remains a synthetic challenge. Here, a crystalline/amorphous composite composed of crystalline Ni 3 Se 4 and amorphous Ni hydroxide with a multi-layered bowl-shaped nanostructure was synthesized by a simple one-step solvothermal method. By regulating the concentration of sulfate ions in the reaction solution, the single-layered nanosheets achieve a transformation into a multi-layered structure with more exposed active sites. In addition, the crystalline-amorphous heterostructure allows regulation of the interfacial electronic structures, and the decoration of Ni 3 Se 4 can effectively enhance the electrical conductivity of composites. Benefiting from the interfacial synergy between Ni 3 Se 4 and Ni hydroxide, the as-optimized Ni 3 Se 4 /Ni hydroxide as an OER catalyst displayed superior electrocatalytic activity with a low overpotential of 285 mV at a current density of 10 mA/cm 2 , a small Tafel slope of 68.3 mV/dec and remarkable stability in alkaline solution. This work offers a novel and effective method for the design of functional crystalline/amorphous composites for energy conversion and storage.
研究领域:
材料科学
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能源化学
✓ 已验证
产品关联
DOI
高影响因子
Nano Energy
·
2022
·
IF 19.069
Junxiu Wu,Hao-Wen Liu,Anwen Tang,Weifeng Zhang,Hwo-Shuenn Sheu,Jyh-Fu Lee,Yen-Fa Liao,Shuping Huang,Mingdeng Wei,Nae-Lih Wu
High-power, fast-charging capability is an urgent issue for the development of advanced Li-ion batteries (LIBs) for electrified mobility applications. An anatase titanium oxide mesocrystal (TOM) Li-ion battery (LIB) anode comprising extremely small (3–5 nm) and crystallographically coherent nanocrystallite subunits demonstrate a high specific capacity (up to 225 mAh g -1 ) and extraordinary rate capability and cycle stability under stressful currents (83 % capacity retention after 9000 cycles at 10 C rate, 1 C = 168 mA g -1 ), considerably outperforming the conventional nanocrystalline titanium oxide (TO) electrode. The investigation of the underlying (de)lithiation mechanism using synchrotron X-ray analyses and density functional theory calculations reveals a novel crystalline–amorphous–crystalline pathway for TOM involving an amorphous phase existing within a Li stoichiometry range approximately Li x TiO 2 , x = 0.2–0.9. The combination of structure amorphization and existing of a fast inter-grain diffusion network inherent to the hierarchical interior of mesocrystal empowers the TOM electrode with orders-of-magnitude higher diffusion rates as compared with the TO electrode. The single-crystal-like crystallographic coherence of the (de)lithiation end-products enables favorable chemo-mechanical stability to avert particle cracking during high-rate cycling. The study indicates a potential new direction for engineering cycle-stable fast-charging electrode materials.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
LANGMUIR
·
2024
·
IF 3.7
Zhe Zheng,Kaiyu Dong,Xiaotong Yang,Qiang Yuan
Metallenes have received sustained attention owing to their unique microstructure characteristics and compelling catalytic applications, but the synthesis of multielement crystalline–amorphous metallenes remains a formidable challenge. Herein, we report a one-step wet chemical reduction method to synthesize composition-tunable crystalline–amorphous heterophase PdMoCrW tetrametallene. As-synthesized PdMoCrW tetrametallene is composed of approximately six to seven atomic layers and has flexible crimpiness, a crystalline–amorphous heterophase structure, and high-valence metal species. Time-dependent experiments show that PdMoCrW tetrametallene follows a three-step growth mechanism that includes nucleation, lateral growth, and atom diffusion, respectively. The novel ultrathin structure, optimized Pd electronic structure, and hydrophilic surface together greatly promote the activity and stability of PdMoCrW tetrametallene in the alkaline oxygen reduction reaction. Pd75.9Mo9.4Cr8.9W5.8/C exhibits excellent mass and specific activities of 2.81 A mgPd–1 and 4.05 mA cm–2, which are 20.07/14.46 and 23.42/16.20 times higher than those of commercial Pt/C and Pd/C, respectively. Furthermore, a Zn–air battery assembled using Pd75.9Mo9.4Cr8.9W5.8/C as a cathode catalyst achieves a peak power density of 156 mW cm–2 and an ultralong durability of 329 h. This study reports an effective strategy for constructing crystalline–amorphous quaternary metallenes to advance non-Pt electrocatalysts toward oxygen reduction reaction (ORR) performance and for a Zn–air battery.
研究领域:
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2025
·
IF 8.3
Jiaxing Zhang,Ningzhao Shang,Yihan Lu,Shangyang Li,Wei Gao,Xiang Cheng,Shutao Gao,Chun Wang
Electrocatalytic two-electron oxygen reduction reaction (2e − ORR) is considered one of the most promising approaches to replace the traditional anthraquinone method for hydrogen peroxide synthesis. Developing advanced electrocatalysts with excellent two-electron activity and selectivity remains challenging. In this study, an interfacial engineering regulation strategy is proposed to construct crystalline-amorphous heterogeneous catalysts by introducing crystalline Ni 2 P via in-situ phosphorization of NiMoO 4 nanorods. This structure not only exposes abundant catalytic active sites but also effectively enhances the overall conductivity of the catalyst. The novel Ni 2 P-NiMoO x exhibits remarkable 2e − ORR performance, with the H 2 O 2 selectivity exceeding 92 % over a wide voltage range. Remarkably, a high H 2 O 2 production rate (4009 mmol g −1 h −1 ) is achieved by Ni 2 P/NiMoO x in H-cell test, which is 3.1 times higher than that of NiMoO 4 and 1.5 times greater than that of Ni 2 P. This study indicates the significant potential of crystalline-amorphous heterojunctions to improve the performance of 2e − ORR electrocatalysts.
研究领域:
材料科学
·
电催化
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS TODAY
·
2023
·
IF 5.3
Dai Zhang,Yuanyuan Chen,Hanqing Dai,Xuewei Lv,Ruiqian Guo,Qiongrong Ou,Shuyu Zhang
Developing earth-abundant, efficient and durable catalysts toward the hydrogen evolution reaction (HER) is critical for the large-scale deployment of sustainable hydrogen production from renewable energies. Transition metal dichalcogenides (TMDs) are promising candidates for the replacement of precious and state-of-the-art platinum-groups-metals, but their HER performance still needs improvement. Constructing crystalline/amorphous interfaces is effective in terms of creating abundant active sites for boosted catalytic activity. Therefore, in this study, defective crystalline vanadium disulfide/amorphous molybdenum sulfide/reduced graphene oxide (c-VS 2 /a-MoS x /RGO) nanocomposites are fabricated via a combined hydrothermal-plasma method. The HER performance of c-VS 2 /a-MoS x /RGO is optimized by tuning the plasma treatment duration and the amount of precursors, and the corresponding mechanisms were investigated by morphological and elemental analyses. Taking advantage of the high reactivity of low-temperature plasma, the strategy presented in this work is effective in terms of constructing crystalline/amorphous interfaces and introducing multiple defects, which creates abundant active sites and ultimately results in boosted HER performance. The optimal c-20VS 2 /a-40MoS x /RGO catalyst exhibited excellent HER activity (η@100 mA cm −2 = 193 mV and η@500 mA cm −2 = 244 mV) and good stability. This work provides a facile and effective strategy for promoting the HER performance of TMDs and sheds light on rationally designing efficient HER catalysts using earth-abundant elements.
研究领域:
材料科学
·
化学工程
·
可再生能源
✓ 已验证
产品关联
DOI
高影响因子
ChemSusChem
·
2025
·
IF 6.6
Yue Wang,Han Qin,Xiangming Wang,Feng Yan,Yang Zhao,Xianbo Yu
Graphical A hierarchical heterostructure consisting of amorphous FeNi(OH) X nanosheets electrodeposited on crystalline Ni 3 S 2 scaffolds with abundant catalytic active sites and superior electronic conductivity is reported to enhance its catalytic activity and long-term stability for overall water splitting. The advancement of inexpensive and productive bifunctional electrocatalysts for overall water splitting is essential for achieving hydrogen energy production. Herein, a hierarchical heterostructure catalyst composed of amorphous FeNi(OH) X nanosheets supported on a crystalline Ni 3 S 2 scaffold, which is anchored to nickel foam through a combined hydrothermal-electrodeposition strategy, is reported. The crystalline Ni 3 S 2 framework exhibits metal-like electrical conductivity and optimized hydrogen adsorption kinetics, while the amorphous FeNi(OH) X overlayer offers abundant adaptive active sites that enhance oxygen evolution reaction (OER) activity. The interfacial charge redistribution decreases the activation energy required for water splitting and accelerates the proton-coupled electron transfer process. Electrochemical tests demonstrate that the catalyst achieves performance at a current density of 10 mA cm −2 , with hydrogen evolution reaction (HER) and OER overpotentials as low as 78 and 183 mV, respectively. In addition, an alkaline electrolyzer assembled with this catalyst serving as both cathode and anode can sustain a current density of 10 mA cm −2 with only 1.51 V and keep a long-term stability exceeding 100 h, surpassing the performance of commercial Pt/C||IrO 2 systems. This study provides a design paradigm that integrates conductive crystalline frameworks with amorphous layers, addressing the tradeoff between conductivity and catalytic multifunctionality in nonprecious metal electrocatalysts.
研究领域:
电化学
·
催化
·
材料科学
·
能量转换
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）