JOURNAL OF CHEMICAL PHYSICS
·
2024
·Vol. 160
·期 9
·
IF 3.1
Lin Yuda,Chen Yiheng,Qiu Liting,Zheng Shenghui
In view of the inherent pseudocapacitance, rich redox pairs (Nb 5+ /Nb 4+ and Nb 4+ /Nb 3+ ), and high lithiation potential (1.0–3.0 V vs Li/Li + ), Nb 2 O 5 is considered a promising anode material. However, the inherent low electronic conductivity of Nb 2 O 5 limits its lithium storage performance, and the rate performance after carbon modification is still unsatisfactory because the intrinsic conductivity of Nb 2 O 5 has not been substantially improved. In this experiment, taking the improvement of the intrinsic electrical conductivity of Nb 2 O 5 as the guiding ideology, we prepared F-doped Nb 2 O 5 @fluorocarbon composites (F–Nb 2 O 5 @FC) with a large number of oxygen vacancies by one-step annealing. As the anode electrode of lithium-ion batteries, the reversible specific capacity of F–Nb 2 O 5 @FC reaches 150 mA g −1 at 5 A g −1 after 1100 cycles, and the rate performance is particularly outstanding, with a capacity up to 130 mA g −1 at 16 A g −1 , which is far superior to other Nb 2 O 5 @carbon-based anode electrodes. Compared with other single conductivity sources of Nb 2 O 5 @carbon-based composites, the electrical conductivity of F–Nb 2 O 5 @FC composites is greatly improved in many aspects, including the introduction of free electrons by F − doping, the generation of oxygen vacancies, and the provision of a three-dimensional conductive network by FC. Through analytical chemistry (work function, UV–Vis diffuse reflectance spectroscopy, and EIS) and theoretical calculations, it is proved that F–Nb 2 O 5 @FC has high electrical conductivity and realizes rapid electron transfer.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF POWER SOURCES
·
2024
·
IF 8.1
Xuxu Wang,Ruxiu He,Ying Bai,Fen Yao,Shuang Gao,Ping Nie,Limin Chang
T-Nb 2 O 5 is a promising anode material for high power density lithium-ion batteries (LIBs) due to its fast lithium storage capacity and safe lithiation potential. However, its practical application is hindered by its low electronic conductivity. In this work, we improved the electrochemical performance of T-Nb 2 O 5 by surface P-doping and the N-doped carbon substrate. Surface P-doping guided by defects enhances the electronic conductivity of the material, which can synergize with N-doped carbon substrates to form a conductive network and accelerate the lithiation/delithiation process. More importantly, surface P-doping does not destroy the internal crystal structure of the material, ensuring the stability of the Nb 2 O 5 during the charge/discharge process. When used as the anode for LIBs, the Nb 2 O 5 -P/N-C exhibits great cycling stability and high-current charge/discharge performance. The specific capacity of Nb 2 O 5 -P/N-C exceeds 116 mAh g −1 after 1000 cycles at 1000 mA g −1 . This work presents a novel approach to improve the electrochemical performance of T-Nb 2 O 5 .
研究领域:
材料科学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2023
·
IF 6.7
Yiqing Lu,Zhimin Zou,Yu Bai,Chunhai Jiang
Although SiO/G (G denotes graphite) products are commercially available in nowadays, their scalable applications in Li-ion batteries are still limited by their poor stability and high cost. Herein, niobium oxide (Nb 2 O 5 ) with open tunnel structure is composited with SiO in combination with N-doped carbon (NC) coating, which have jointly enhanced the rate and cycle performance of the resulting SiO@Nb 2 O 5 @NC composite anodes. Under optimum conditions, a capacity retention of 74% is preserved after 200 cycles at 0.2 A g −1 , together with a high capacity of 666 mA h g −1 at 3 A g −1 . Ex situ XRD analysis reveals that Nb 2 O 5 is transformed to amorphous Li x Nb 2 O 5 and electrochemical-inert NbO in the first lithiation process. The former exhibits fast Li + migration rate and capacitive Li ion storage behavior, which may help to improve the electrochemical performance of SiO. Further mixing the SiO@Nb 2 O 5 @NC composite with spent graphite extracted from used LiFePO 4 battery yields a high capacity and stable anode material that shows a high capacity retention of 79% after 500 cycles at 0.4 A g −1 . This work may shed a light on the development of stable yet low cost SiO/G anode materials through pre-modification of SiO with Nb 2 O 5 and utilization of cheap graphite resource.
研究领域:
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Qing Ji,Weiheng Chen,Xiaoping Chen,Xiaoyan Wang,Qingyu Dong,Shanshan Yin,Yanbin Shen,Peter Müller-Buschbaum,Ya-Jun Cheng,Yonggao Xia
Niobium pentoxides (Nb2O5) present great potential as next-generation anode candidates due to exceptional lithium-ion intercalation kinetics, considerably high capacity, and reasonable redox potential. Although four phases of Nb2O5 including hexagonal, orthorhombic, tetragonal, and monoclinic polymorphs show diverse characteristics in electrochemical performance, stable lifetime, high specific capacity, and fast intercalation properties cannot be delivered simultaneously with a single phase. Herein, this issue is addressed by generating a homogeneous mixture of orthorhombic and monoclinic crystals at the nanoscale. Reversible lithium-ion intercalation/deintercalation of the monoclinic phase is achieved, and exceptional lithium storage sites are created at the interface of the two phases. As a result, electrochemical features of stable lifetime from the orthorhombic phase and high specific performance from the monoclinic phase are harmoniously combined. This dual-phase Nb2O5/C nanohybrids deliver as high as 380 mA h g–1 (0.01–3.0 V) and 184 mA h g–1 (1.0–3.0 V) after 200 cycles. The essential principle of property enhancement is further confirmed through in situ XRD measurements and DFT calculations. The dual-phase concept can be further applied on electrodes with multiphases to achieve high electrochemical performance.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Wanxing Zhang,Pengcheng Mao,Yuhang Jin,Hai Ming,Zhipeng Li,Danfeng He,Hongyu Sun,Yanlong Yu,Yanguo Liu
Niobium pentoxide (Nb 2 O 5 ) anodes have attracted much attention as a candidate for the next generation lithium-ion batteries (LIBs) due to the unique physical and chemical properties. However, some critical issues, like low electronic conductivity, inefficient ionic diffusion, must be addressed before practical applications. In this work, we employed a facile NaBH 4 engaged chemical reduction method to modify Nb 2 O 5 anodes. Microstructure and surface chemistry analysis indicated that the Nb 2 O 5 materials have micro/nanoscale three-dimensionally interconnected morphology, and contain three different phases (T-, M-, and H-Nb 2 O 5 ). More importantly, oxygen vacancies are introduced by the NaBH 4 reduction treatment, and the oxygen vacancy amount can be modulated by changing the NaBH 4 concentration. As anodes for LIBs, the optimized sample exhibited a reversible capacity of 252.2 mAh·g −1 after 100 cycles at a current density of 1 C, and a reversible capacity of 139.4 mAh·g −1 at a large current density of 10 C. The electrochemical performance enhancement can be attributed to the combination of multiscale structural design, i.e., oxygen vacancy, nanoscale phase interface , and micro/nanoscale three-dimension assembly. We expect the present synergistic strategy can be employed to manipulate the key structures in different functional materials for broader applications.
研究领域:
材料科学
·
能源存储
✓ 已验证
DOI
高影响因子
INORGANIC CHEMISTRY COMMUNICATIONS
·
2023
·
IF 3.8
Xinyu Tian,Qunchao Qi,Bin Hou,Yannan Qian
We exploited a simple hydrothermal route without adding organic additives or hard templates to synthesize cubic-shaped LiNbO 3 :Yb 3+ /Er 3+ with the size of 400–500 nm. Based on the time-dependent investigation on the crystal structure and morphology, Yb(NO 3 ) 3 and Er(NO 3 ) 3 not only could emit green and red upconversion (UC) emission but also could be used as an etchant to increase dissolution rate of the Nb 2 O 5 raw material in the hydrothermal synthesis route. Without addition of Yb 3+ /Er 3+ ions, LiNbO 3 phase could not be formed at even hydrothermal time of 48 h. The time-dependent Raman spectra showed the Raman peaks of LiNbO 3 were occurred at the reaction time of 48 h, and the impurity Nb 2 O 5 phase was disappeared with lengthening hydrothermal time. After calcining at 1050 °C for 2 h, the new Raman peaks at 440/487/531/552 cm −1 and the disappeared OH – absorption peaks at 3429 and 1628 cm −1 favored to produce the bright UC emissions in LiNbO 3 :Yb 3+ /Er 3+ nanocrystals. The pump power dependence and UC mechanism were studied under 980 nm excitation.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Zhengren Tao,Fangrui Cheng,Yinghan Wang,Sijie Su,Enhai Song,Jiulin Gan,Shi Ye
The arrangement of lithium and niobium in the LiNbO 3 lattice is crucial to its notable ferroelectric, piezoelectric, ion conductive, and nonlinear optical properties. However, the synthesis of Li concentration-gradient nanocrystals remains a significant challenge. In this paper, we report a reliable method for synthesizing LiNbO 3 : Yb/Er nanocrystals with a Li-gradient through topochemical molten salt synthesis. We elucidate the Li-gradient characteristics using various analytical techniques, including depth-dependent elemental analysis. Variable-temperature upconversion luminescence spectroscopy provided insights into thermally induced surface and interior Li + diffusion. Our findings demonstrate that Li-gradient nanocrystals exhibit enhanced ferroelectric behavior and increased sensitivity to mechanical force in upconversion emission response. This study proposes a feasible universal strategy for synthesizing alkali metal niobate materials with controlled polarization, offering promising candidates for flexible, low-power optoelectronic devices.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2021
·
IF 3.498
Huibin Ding,Zihan Song,Kai Feng,Hongzhang Zhang,Huamin Zhang,Xianfeng Li
It’s challenging to obtain pure-phase metastable tetragonal niobium pentoxide (M-Nb 2 O 5 ) by conventional heating methods, due to the thermodynamical stable temperature region of M-Nb 2 O 5 partially overlaps with that of H- or T-type Nb 2 O 5 . Herein, the pure-phase M- Nb 2 O 5 is synthesized by utilizing the confinement of amorphous SiO 2 shells, and the pure-phase M-Nb 2 O 5 (without SiO 2 ) is investigated as anode material of lithium-ion batteries. The shells can not only cut off the mutual integration among Nb 2 O 5 particles, but also inhibit the rearrangement and mobility of the atoms inside via forming Si-O-Nb bond at the interface, thus could widen the thermodynamic and kinetic stability stable regions of the M-Nb 2 O 5 . The physical and electrochemical performance of pure M-Nb 2 O 5 (without SiO 2 ) is characterized as the anode material of lithium-ion batteries, which exhibits an initial capacity of 246 mAh g - 1 , unprecedented high-rate performance (≈86 mAh g - 1 at 4.0 A g - 1 ) and excellent cycling stability (≈78 mAh g - 1 at 2.0 A g - 1 after 1000 cycles).
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Yuanyuan Hu,Dangli Gao,Xiangyu Zhang,Sining Yun
Persistent luminescence (PersL) that carries remote information is of paramount importance for intelligent anti-counterfeiting applications. However, the feeble PersL intensity, along with its uncontrollability, hamstrings their practical utilization. Here we develop LiNbO 3 (LNO):Pr,Bi phosphor with enhanced red PersL by trace doping of Sm 3+ . The LNO:Pr,Bi,Sm phosphor exhibits quadruplet luminescence, namely polychrome photoluminescence, PersL, and photo/thermo-stimulated luminescence (PSL/TSL). Particularly, the enhanced TSL can carry remote subjective information independent of the phosphor itself by controlling the temperature. A mechanism of PersL enhancement is proposed based on constructing reversible photovoltaic cells and electrolytic cells by photothermal redox reactions using Bi 3+ + V O and Bi 3+ /Pr 3+ + V Li ' ion pair. This study has initiated the exploration of designing information storage PersL materials for more sophisticated remote intelligent anti-counterfeiting.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materiomics
·
2023
·Vol. 10
·期 5
·995-1003
·
IF 9.4
Wei Peng,Jianglei Chang,Jianwei Zhao,Dawei Wang,Zhen Liu,Genshui Wang,Shuxiang Dong
Piezoelectric PZT ceramics with high piezoelectric properties and good thermal stability are urgently desired concerning the practical application. New compositions of LiNbO 3 modified Pb(Ni 1/3 Nb 2/3 )O 3 PbZrO 3 PbTiO 3 ceramics have been prepared in this study. The effects of the introduction of the LiNbO 3 on the system were comprehensively investigated in terms of the phase structure, microstructure, electric properties, and thermal stability behavior of the ceramics. All compositions are located in the morphotropic phase boundary (MPB) region, and the ratio of the rhombohedral (R) phase increases obviously with the increase of LiNbO 3 concentration. With increasing the LiNbO 3 content, the piezoelectric properties were significantly enhanced. The sample added with 2% (in mole) LiNbO 3 shows excellent electric properties, including T m = 185 °C, ε r = 5,643, k p = 0.626, Q m = 51, d 33 = 902 pC/N. More importantly, no thermal depolarization behavior was observed in the temperature range of 25–100 °C. For PNN-PZT- x %LN ceramics, which is mainly attributed to the pinning effect resulted by the Li Pb ' − Nb Zr/Ti ∙ defect dipoles.
研究领域:
材料科学
·
功能陶瓷
·
压电材料
·
固态物理
·
电子材料
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·Vol. 50
·期 4
·6598-6605
·
IF 5.2
Wei Peng,Jianglei Chang,Bin Wang,Zhen Liu,Genshui Wang,Shuxiang Dong
The ultrahigh piezoelectric coefficient (d 33 ≥ 1000 pC/N) exhibited by piezoelectric Pb(Zr,Ti)O 3 (PZT) ceramics not only captivates researchers but also holds considerable practical value across various applications. While significant progress has been made in enhancing piezoelectricity of PZT-based ceramics, novel mechanisms need to be proposed to explain the piezoelectric behavior of new systems with ultrahigh d 33 . In this study, we initially employ LiNbO 3 as an additive to enhance the piezoelectric properties of the Pb(Ni 1 / 3 Nb 2 / 3 )O 3 –PbZrO 3 –PbTiO 3 ceramics. and the optimal performance is achieved by incorporating 1.5 mol% of LiNbO 3 into the system, resulting in an ultrahigh d 33 ∼1178 pC/N ( d 33 * ∼1560 p.m./V (@ E = 5 kV/cm)). The corresponding mechanism for this superior piezoelectric response involves the AB-site co-doping effect, especially the ( Li Pb ′ − Nb Zr / Ti ∙ ) defect dipoles formed by the introduction of LiNbO 3 . In particular, the addition of LiNbO 3 leads to a more uniform distribution of domain sizes, thereby further enhancing the ultrahigh piezoelectricity. These findings pave the way for a deeper under-standing of the origin of ultrahigh piezoelectric properties and make substantial contributions to the advancement of piezoelectric materials for practical applications in electromechanical devices.
研究领域:
材料科学
·
功能陶瓷
·
压电材料
·
固态物理
·
电子显微学
·
介电材料
·
无机非金属材料
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2022
·
IF 7.336
Yifan Zhang,Laifu Yang,Wenqiang Wang,Gengchao Wang
LiNbO 3 is an intercalation material with high theoretical specific capacity, which is promising for lithium-ion capacitor (LIC) anode. However, the poor charge transfer dynamics makes LiNbO 3 unable to match the capacitive cathode in rate performance and cycle stability, resulting in poor electrochemical performance of the device. Herein, through the integrated process of in-situ nitrogen-doping with polypyrrole as the nitrogen source and hydrothermal deposition, the coaxial heterostructure of ultrafine LiNbO 3 nanoparticles and nitrogen-doped carbon nanotubes (NCNT) was realized. The large lithium-ion accessible surface and the bonding with the conductive channel significantly enhance the pseudocapacitive behavior of LiNbO 3 (capacitance contribution of 78.5% at 1 mV s −1 ). After 1000 cycles at a current density of 2 A g −1 , NCNT@LiNbO 3 still has a specific capacity of 154.9 mAh g −1 (89.8%). Thus, the assembled NCNT@LiNbO 3 //AC devices can charge and discharge up to 10000 cycles at a current density of 2 A g −1 , and the capacity retention rate can still reach 90.3%, and can provide an energy density of 142 Wh kg −1 . This work provides ideas for the interface and structure design of nanocomposite electrode materials.
研究领域:
材料科学
·
电化学
·
纳米复合材料
·
能源存储
·
界面工程
·
电极设计
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）