JOURNAL OF POWER SOURCES
·
2024
·
IF 8.1
Yulei Wang,Ruotong Li,Bin Feng,Tao Long,Kairong Wang,Qinqin Yu,Zuyong Wang,Yuan-Li Ding
Fast charging and all-climate electrochemical behaviors are two of the most important issues of olivine cathodes for lithium ion batteries (LIBs) owing to inferior Li + and electron conduction at a high current density or low temperature. Taking Mn-containing olivine cathode (LiFe 0.8 Mn 0.2 PO 4 , LFMP) as an example, herein, we report a facile interconnected, hierarchically porous and highly conductive framework design strategy to construct an advanced bulk LFMP@graphene hybrid, realizing superior fast charging capability and wide temperature performance (−20∼80 °C). Such hybrids not only offer well-interconnected and highly conductive graphene networks, but also possess hierarchical porous interiors where the former ensures high-efficiency charge transfer between active components while the latter facilitates Li + diffusion. Benefiting from these advantages, the obtained hybrids deliver superior rate capability (85.0 mAh g −1 up to 20C) and high capacity retentions of 94.1 % after 3000 cycles at 10C (50 °C), and 91.7 % after 500 cycles at 5C (80 °C), and 93.6 % after 1300 cycles at 1C (−20 °C). This work provides an efficient strategy to design practical olivine cathode at the material level for fast charging and all-climate LIBs.
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DOI
高影响因子
JOURNAL OF FLUORESCENCE
·
2024
·
IF 2.6
Zha Jiahao,He Chongjun,Chen Fangzhou,Wang Hongwei,Dong Biao,Liu Lijuan,Xia Mingjun,Deng Chenguang,Li Qian,Lu Yuangang,Chen Huiting
Oxide matrix red-emitting phosphors are deemed as excellent color converters for white light emitting diodes (WLEDs) and laser diodes (LDs). Manganese-doped MgAl 2 O 4 powder was synthesized by a solid-state reaction method at different sintering temperatures. Microstructure shows that grain size is mainly in the range of 0.2–5 μm, and grain agglomeration occurs with increased sintering temperature. XPS analysis indicates that the doped Mn ion exhibits a valence state of + 4 within the MgAl 2 O 4 matrix. The diffraction peak of the phosphors is shifted by the sintering temperature, which affects lattice constant. Upon excitation by 300 nm ultraviolet light, the samples emit asymmetric broadband red light within the range of 620–720 nm, attributed to Mn 4+ ion’s transition from 2 E g to 4 A 2g states. With the increasing temperature, the main emission peak shifts from 677 nm to 650 nm, ascribed to the change in energy level ( 2 E g ) resulting from the reduction of Al 2 O 3 phase. Crystal field theory confirmed that Mn 4+ ions are within a strong crystal field environment created by MgAl 2 O 4 matrix. By affecting particle size and crystallinity, the sintering temperature influences the fluorescence lifetime of the Mn 4+ ion. Notably, these red-emitting phosphors exhibits remarkable thermal stability as their emission intensity remains approximately at 58% of initial intensity even at elevated temperature (435 K). Consequently, Mn 4+ : MgAl 2 O 4 red-emitting phosphors with high thermal stability render them promising candidates for WLED applications.
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DOI
高影响因子
Functional Materials Letters
·
2024
·
IF 1.2
Zhuqing Sun,Yongxia Li,Haowen Bai,Shenghang Jin,Haibo Zhang,Guanying Cao
All inorganic lead halide cesium perovskite quantum dots (QDs) have attracted much attention due to their excellent luminescence properties, but further development is restricted by their stability and the existence of toxic element lead. In this paper, F/Mn-doped CsPb ( Br / Cl ) 3 QDs glass was prepared by melt quenching and heat treatment, with reduced Pb content effectively. The result shows that the spectrum of the QD glass is adjustable between 450 nm and 515.4 nm by changing the feeding ratio of Mn-Pb ion and heat treatment temperature. Moreover, the indraught of Mn 2 + effectively improves the PLQY of CsPb ( Br / Cl ) 3 QDs glass and serves as a red-emitting. The prepared composites not only maintain good fluorescence characteristics, but also greatly improve the stability of QDs. And successfully coupled with blue LED chips to synthesize WLED, Under 20 mA current, the color coordinate is (0.3446, 0.3389).
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高影响因子
NANOTECHNOLOGY
·
2023
·Vol. 34
·期 14
·145403
·
IF 3.5
Huiying Wang,Ziyan Kong,Minghao Wang,Bing Huang,Lunhui Guan
Manganese and nitrogen co-doped porous carbon (Mn–N–C) are proposed as one of the most up-and-coming non-precious metal electrocatalysts to substitute Pt-based in the oxygen reduction reaction (ORR). Herein, we chose metal triazole frameworks as carbon substrate with hierarchical porosity for trapping and anchoring Mn-containing gaseous species by a mild one-step pyrolysis method. The optimized Mn–N–C electrocatalyst with a large metal content of 1.71 wt% and a volume ratio of 0.86 mesopores pore delivers a superior ORR activity with a half-wave potential (E1/2) of 0.92 V in 0.1 M KOH and 0.78 V in 0.1 M HClO4. Moreover, the modified Mn–N–C catalyst showed superior potential cyclic stability. The E1/2 remained unchanged in 0.1 M KOH and only lost 6 mV in 0.1 M HClO4 after 5000 cycles. When applied as the cathode catalyst in Zn-air battery, it exhibited a maximum peak power density of 176 mW cm−2, demonstrating great potential as a usable ORR catalyst in practical devices.
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DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2024
·
IF 5.8
Dezhi Wang,Jiasen Wang,Xuebao Li,Cheng Han,Hao Fei,Zhuangzhi Wu
In the pursuit of enhancing the energy density of lithium-ion batteries, cathode prelithiation emerges as a pivotal approach, introducing additional irreversible active lithium ions to augment performance. Li 5 FeO 4 (LFO) stands out as an excellent option, boasting an impressive theoretical specific capacity and the additional advantages of cost-effectiveness in raw materials and low preparation cost. However, the impact of extra lithium incorporations on compositional changes at the electrode-electrolyte interface as well as on cell stability has impeded further researches. Herein, a Mn doping strategy is proposed and predicted by first-principles calculations to synthesize partially Mn-substituted Li 5.125 Fe 0.875 Mn 0.125 O 4 (LFMO). And the prelithiation with LFMO improved the interfacial composition of LiFePO 4 (LFP) batteries compared to LFO, achieving a charging capacity of 213 mAh∙g −1 in the first cycle at 0.05 C. The subsequent treatment demonstrated superior cycling stability, maintaining a discharge specific capacity as high as 155.3 mAh∙g −1 after 100 cycles at 0.2 C, and exhibiting a higher capacity retention in the full cell. These discoveries could contribute to enhancing the regulation of battery interface during the utilization of LFO, potentially promoting the development of cathode lithium additives.
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高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2021
·Vol. 28
·期 30
·41504-41515
·
IF 4.223
Zhao Kang-He,Ma Yu-Long,Lin Feng,Ge Shao-Ying,Zhu Li
A composite Mn-Cu-Ce tri-metal oxide supported on γ-Al 2 O 3 (Mn-Cu-Ce/Al 2 O 3 ) catalyst was prepared by an impregnation-calcination method and investigated in the catalytic ozonation treatment of real coal chemical wastewater (CCW). The catalyst was characterized by XRD, SEM, TEM, XRF, BET, and XPS techniques. The results showed that Mn, Cu, and Ce metal oxides were evenly distributed on the Al 2 O 3 surface and the catalyst maintained a large surface area and a high pore volume compared with the pristine Al 2 O 3 . The synergy between Mn, Cu, and Ce oxides greatly enriched the catalytic active sites and enhanced the ozonation performance. The catalytic ozonation process with Mn-Cu-Ce/Al 2 O 3 increased the removal rate of total organic carbon (TOC) by 31.6% compared with ozonation alone. The ketones, aromatic compounds, phenols, and nitrogen-containing heterocyclic compounds in CCW have been effectively degraded and mineralized by Mn-Cu-Ce/Al 2 O 3 catalytic ozonation process, and its biodegradability has also been significantly improved. The experimental results of ∙OH scavengers revealed that the mechanism of Mn-Cu-Ce/Al 2 O 3 catalytic ozonation was to promote the generation of ∙OH radicals. The catalytic activity of Mn-Cu-Ce/Al 2 O 3 was only a slight decrease in six consecutive catalytic ozonation treatments, showing good stability. Therefore, Mn-Cu-Ce/Al 2 O 3 can be used as a candidate catalyst for the advanced treatment of refractory organic wastewaters upon catalytic ozonation.
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高影响因子
JOURNAL OF LUMINESCENCE
·
2022
·
IF 4.171
Wenzhi Wang,Shuo Song,Jinkai Li,Bingqiang Cao,Zongming Liu
Halide perovskite quantum dots (QDs) have been considered to be a potential emitting materials for illumination and display applications. Unfortunately, the toxicity and poor stability can greatly limit their practical application. Herein, the Mn 2+ -doped CsPbCl 3 and SiO 2 -coated Cs(Pb,Mn)Cl 3 perovskite QDs have been developed to solve the tricky problem without affecting their optical properties . Firstly, the mono-dispersed pure CsPbCl 3 perovskite QDs with cubic morphologies are prepared by using a modified hot-injection method, as a control group. Next, the low-Pb content Cs(Pb,Mn)Cl 3 perovskite QDs with distinctive dual emission peaks has been successfully obtained, including the CsPbCl 3 host emission and the Mn 2+ emission. Based on this, a new strategy for synthesizing single Cs(Pb,Mn)Cl 3 @SiO 2 core-shell QDs with their initial cubic morphology and optical properties has been developed, which using the Cs(Pb,Mn)Cl 3 nanoparticles as a precursor and choosing the APTES as the surface ligand. Photo-stability tests indicate that the Cs(Pb,Mn)Cl 3 and Cs(Pb,Mn)Cl 3 @SiO 2 perovskite QDs are markedly more stable than the pure CsPbCl 3 QDs, indicating that the crystal engineering and host packaging are all effective way to improve the stability. Meanwhile, the PL intensity of Cs(Pb,Mn)Cl 3 @SiO 2 dispersed in a mixed solution of toluene and water can retained 63% of the initial value even after 14 h, which are much higher than Cs(Pb,Mn)Cl 3 (31%). Therefore, the Cs(Pb,Mn)Cl 3 after SiO 2 coating is the more effective way to improve stability than that of the Mn 2+ doping. This work not only provides a simple and reliable synthesis way to synthesize the single core-shell particles, which can be suitable for other perovskite systems, but also compares the two methods of the crystal engineering and the host packaging to improve the stability of perovskite QDs for practical application.
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高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2020
·
IF 4.65
Siran Xu,Yeshuang Du,Xian Liu,Xin Yu,Chunlin Teng,Xiaohong Cheng,Yunfeng Chen,Qi Wu
Developing earth-abundant and high-efficient catalysts for the oxygen evolution reaction (OER) to enhance the efficiency of water splitting is highly desirable. Metal-doping and construction of heterogeneous structure are two start-of-the-art strategies to increase the OER activity of transition metal materials. In this work, we exhibit the design and construction of a unique coral-like 3D hierarchical Mn-doped Ni 2 P–Ni 5 P 4 /NF (Mn–Ni–P/NF) OER catalyst. The Mn-doped Ni 2 P–Ni 5 P 4 /NF hybrid catalyst is synthesized on Ni foam by hydrothermal and followed in situ phosphidation, which exhibits superior OER catalytic performance with an overpotential of 230 mV (vs. RHE) at a current density of 10 mA/cm 2 and 70 mV lower than Ni 2 P–Ni 5 P 4 /NF (300 mV). Furthermore, it also exhibits good long-term stability for 20 h. This work provides a good thought named metal-doping transition metal phosphide complexes to improve the catalytic activity for OER. Such a superior OER performance is main attributed to the unique morphology, the doping of metal Mn regulating the metal phosphide Ni 2 P–Ni 5 P 4 nanosheet structure to be a 3D rough high-active-sites nanorod structure with the in situ formed oxidized Ni species on the surface and effective composite nanostructures .
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高影响因子
NANOTECHNOLOGY
·
2020
·Vol. 31
·期 39
·395602
·
IF 3.551
Hongchao Geng,Ning Jiang,Chenyi Li,Xingqi Zhu,Yan Qiao,Qingyun Cai
A novel visible light-driven photocatalyst (represented as Mn-CdS/ZCISe/CIS/TiO2) for the passivation of E. coli was prepared with TiO2 nanowires as support and using CuInS2 (CIS) and ZnCuInSe (ZCISe) quantum dots (QDs), as well as Mn-doped CdS (Mn-CdS) nanoparticles (NPs) as sensitizers. The use of CIS and ZCISe QDs and Mn-CdS NPs extends the light harvest region to visible light. The photoelectric conversion efficiency was consequently improved, with a photocurrent density of 12.5 mA cm−2, about 60 times that of pure TiO2 nanowires. The germicidal efficiency of the photocatalyst was assessed by passivation of E. coli, 96% bacteria in 50 ml 105 colony forming units (CFU) ml−1 solution were killed within 50 min. Besides the high efficiency, the composite has good stability and satisfactory recycling performance. The antibiotic mechanism was also performed by using photoluminescence and a scavenging agent of different active matter, revealing that the photo-generated holes play a major role in the sterilization process.
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高影响因子
CHEMISTRY OF MATERIALS
·
2022
·
IF 10.508
Mao-Yin Ran,Sheng-Hua Zhou,Bingxuan Li,Wenbo Wei,Xin-Tao Wu,Hua Lin,Qi-Long Zhu
Simultaneous regulation and control of non-linear second-harmonic-generation (SHG) coefficients (deff) and linear birefringence (Δn) of non-centrosymmetric (NCS) crystals is a crucial aspect of improving the non-linear optical (NLO) performance, yet it remains a huge challenge in modern laser techniques and science. Herein, a series of melilite-type oxide-derived NCS oxychalcogenides, Sr2MGe2OS6 (M = Mn, Zn, and Cd), are successfully designed and synthesized through a facile partial isovalent chemical substitution strategy. These isostructural compounds crystallize in the tetragonal NCS space group P4̅21m (no. 113) and feature unique two-dimensional Cairo pentagonal tiling layers composed of heteroligand [GeOS3] and tetrahedral [MS4] asymmetric building units (ABUs). Compared to the parent melilite-type oxides, the derived title compounds not only successfully realize the phase matchability transformation [i.e., from non-phase-matching (NPM) to phase-matching (PM)] but also greatly improve the IR-NLO performance (especially, simultaneously boosting deff and Δn). Sr2CdGe2OS6 exhibits the best comprehensive performance among oxychalcogenides, including a wide PM cutoff edge (>525 nm), a strong deff (0.8 × AgGaS2), a giant laser-induced damage threshold (19.2 × AgGaS2), a large band gap (3.62 eV), as well as a broad transmission cutoff region (0.28–12.0 μm). Furthermore, highly distorted [GeOS3] ABU in this melilite-type structure is proved to be the profitable bifunctional NLO-active unit, which can contribute to the search and design of novel IR-NLO crystals with a large Δn and a strong deff based on the experimental results and theoretical calculations. This work demonstrates the first examples of PM melilite-type oxychalcogenides and offers new perspectives on the phase matchability transformation through the partial isovalent chemical substitution approach, which will play a constructive role in the future design of high-performance IR-NLO heteroanionic materials.
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高影响因子
JOURNAL OF CHEMICAL PHYSICS
·
2024
·Vol. 160
·期 16
·
IF 3.1
Du Luchao,An Jie,Katayama Tetsuro,Duan Menghan,Shi XiaoPing,Wang Yunpeng,Furube Akihiro
In recent years, all-inorganic perovskite materials have become an ideal choice for new thin film solar cells due to their excellent photophysical properties and have become a research hotspot. Studying the ultrafast dynamics of photo-generated carriers is of great significance for further improving the performance of such devices. In this work, we focus on the transient dynamic process of CsPbBr 3 /TiO 2 composite systems with different Mn 2+ doping contents using femtosecond transient absorption spectroscopy technology. We used singular value decomposition and global fitting to analyze the transient absorption spectra and obtained three components, which are classified as hot carrier cooling, charge transfer, and charge recombination processes, respectively. We found that the doping concentration of Mn 2+ has an impact on all three processes. We think that the following two factors are responsible: one is the density of defect states and the other is the bandgap width of perovskite. As the concentration of doped Mn 2+ increases, the charge transfer time constant shows a trend of initially increasing, followed by a subsequent decrease, reaching a turning point. This indicates that an appropriate amount of Mn 2+ doping can effectively improve the photoelectric performance of solar cell systems. We proposed a possible charge transfer mechanism model and further elucidated the microscopic mechanism of the effect of Mn 2+ doping on the interface charge transfer process of the CsPbBr 3 /TiO 2 solar cell system.
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DOI
PubMed
高影响因子
ADVANCED POWDER TECHNOLOGY
·
2021
·Vol. 32
·期 8
·2940-2949
·
IF 4.833
Shanfang Lan,Qing Hu,Qianqian Zhao,Weihui Jiang,Jianmin Liu,Guo Feng,Feng Jiang,Huidong Tang,Junhua Chen
With the increasing popularity of the black decorative ceramics, the development of black pigment with good properties has become significant for the ceramic industry. A Mn-doped zirconium silicate encapsulated carbon (C@ZrSiO 4 ) black pigment was successfully prepared via non-hydrolytic sol-gel (NHSG) method at 800 °C, while MnCl 2 and carbon-containing precursors (tetraethoxysilane, TEOS) were used as Mn and in-situ carbon sources, respectively. The results demonstrated that the L* value of black pigment first decreased and increased with the increase of MnCl 2 content. The as-prepared pigment with the MnCl 2 content of 10 mol% showed a deep dark hue ( L* = 27.64, a* = 0.67, b* = 0.68), while the pigment without Mn doping exhibited poor chromatic properties ( L * = 51.18). Moreover, XPS and EPR results indicated that the Mn(II) and Mn(IV) replaced the Zr(IV) in ZrSiO 4 , resulting in the formation of oxygen vacancies. In-situ carbon provided by TEOS incorporated into these oxygen vacancies, which can protect carbon from being oxidized. In addition, the prepared pigment exhibited higher chemical stability in acid/alkali solutions, favorable tinting strength and thermal stability in base transparent glaze, which displayed wide application prospect in the field of ceramic decoration.
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高影响因子
危险品化学品经营许可证（带存储）