International Journal of Electrochemical Science
·
2023
·
IF 1.5
Yiqi Cui,Chengyi Zhu,Rui Huang,Jiaming Liu,Yannan Zhang
LiMn 2 O 4 is regarded as a promising positive material candidate for contemporary lithium-ion batteries (LIBs) in terms of high safety, low cost, and environmental benignity. However, the spinel LiMn2O4 electrodes suffer from rapid capacity fades during lithiation and delithiation at high temperatures. Herein, we describe a simple sol-gel reaction method to modify the surface of LiMn2O4 materials and fill the gaps between particles by LaPO 4 to improve its electrochemical performance and utilization in the room and high temperature. As a result, the as-prepared LiMn 2 O 4 @ LaPO 4 electrode delivers excellent reversible capacity retention of 81.3% after 200 cycles at 1 C rate and exhibits a remarkable capacity of 74.9 mAh g -1 at 10 C rate. Moreover, Mn dissolution measurement reveals that LaPO 4 coating can effectively reduce the manganese dissolution in electrolytes at high temperatures. This general surface-modification strategy will have implications in practical applications for long-life lithium-ion batteries.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2021
·Vol. 56
·期 12
·7494-7507
·
IF 4.22
Zhang Rui,Yuan Yaoxin,Zhang Jianfeng,Liu Haiyun,Chen Gang,Li Kun,Hong MengQing,Zuo Wenbin,Wang Chunlan,Yang Wen,Qin Zhenxing
Mn-doped perovskite CsPb(Cl/Br) 3 nanocrystals (NCs) have been widely explored due to their unique dual-color emission characteristics, which could reduce the usage of toxic Pb and introduce the exciton emission in blue region and the stable Mn 2+ emission peak in orange-red region via energy transfer from exciton to Mn 2+ emission. Although doping high concentration Mn 2+ could increase the Mn 2+ emission, excess Mn 2+ ions would be expelled from the host perovskite lattice. Doping secondary metal Ni into the NCs as an efficient method is always used to improve the Mn 2+ emission. We adopted a one-pot halogen injection into Cs-precursor under ambient environment method to prepare (Mn, Ni): CsPbCl 3 and (Mn, Ni): CsPb(Cl/Br) 3 NCs, which introduces NiCl 2 in the Mn: CsPb(Cl/Br) 3 NCs to supply enough halide ions and to passivate defect states or traps in the perovskite NCs so as to enhance Mn 2+ emission. Density Functional Theory (DFT) calculations were also conducted to explain our experimental results, which revealed that Ni 2+ doping could eliminate the in-gap deep defects of the CsPb(Cl/Br) 3 nanocrystals. In addition, the passivated lattice defects help to improve the stability of the perovskite NCs, preventing from electron beam irradiation.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2022
·Vol. 29
·期 51
·77536-77552
·
IF 5.19
Xue Yun,Cheng Wanting,Cao Meng,Gao Jianzhang,Chen Jiaqi,Gui Yunyang,Zhu Wenmin,Ma Fuqiu
In this paper, nitric acid-modified activated carbon was used as an electrode in the electrosorption process for the removal of Co 2+ , Mn 2+ , and Ni 2+ from wastewater. The effects of applied voltage, initial pH, and coexisting ions on removal efficiency were investigated. The adsorption process was evaluated by adsorption isotherm models. The results indicated that the electrosorption process was consistent with the Langmuir model, proving that the electrosorption process was a monolayer adsorption process. The maximum adsorption capacities of Co 2+ , Mn 2+ , and Ni 2+ were 131.58 mg/g, 102.04 mg/g, and 103.09 mg/g. Electrochemical tests revealed that the specific capacitance of AC-HNO 3 was 54.11 F/g when the scanning rate was 5 mV/s, while the specific capacitance of AC was 36.51 F/g. The Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) confirmed that the content of oxygen groups on the surface of activated carbon increased after modification, which provided more adsorption sites for electrosorption. When the selected concentration of HCl was used as the eluent, the elution efficiency of Co 2+ , Mn 2+ , and Ni 2+ could reach 94.23%, 93.65%, and 90.61%. The removal efficiency could reach more than 95% after three cycles. The results of the study can be used as a reference significance for the removal of cobalt, manganese, and nickel ions from heavy metal wastewater by electrosorption.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
Journal of Environmental Sciences
·
2022
·
IF 6.796
Rui Liu,Huan-Huan Yang,Hao Zhou,Xianliang Yi,Yang Liu
Particulate matter (PM) is the main contributor to air pollution, and filtration has been reported to be promising for PM capturing. Considering the complexity of polluted air (volatile organic compounds (VOCs) and ozone are likely concomitant with PM particles) and in view of the versatility of MnO 2 for the degradation of VOCs and ozone, the feasibility of MnO 2 materials as PM filtering media was investigated in this study, and the effect of crystal structure on PM filtration was clarified. Compared with the layered δ-MnO 2 , the MnO 2 with tunnel structure (including 1 × 2-, 2 × 2- and 3 × 3-MnO 2 ) exhibited greatly enhanced PM removal efficiencies, and particularly, the 3 × 3-MnO 2 possessed not only significant activity for adsorbing PM particles but also high utilization efficiency of the active surface. Physicochemical properties of the adsorbents were studied by XRD, ATR, isothermal N 2 adsorption, SEM and (HR)TEM. The correlation between pore characteristics and particle elimination activity demonstrates that the most developed mesoporous structure of the 3 × 3-MnO 2 sample played an important role in strengthening the PM adsorption capability. Further comparison of the surface properties of the fresh and spent samples reveals that with respective to the occasion of δ-MnO 2 , the structure of 3 × 3-MnO 2 was robust enough to resist collapse after PM capturing and the great accommodation of the inorganic and organic PM substances in the voluminous pores induced strong affinity between PM particles and 3 × 3-MnO 2 . Thereby, a higher particle filtration ability was retained.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
Catalysis Science & Technology
·
2019
·Vol. 9
·期 18
·5090-5099
·
IF 5.726
Yi Yu,Shuilian Liu,Jian Ji,Haibao Huang
Ozone pollution has aroused worldwide concern for its adverse impact on both the environment and human health. A series of MnO2 catalysts with different crystallinities were prepared for ozone decomposition. The crystallinity of MnO2 was regulated by varying the calcination temperature of an amorphous MnO2. The calcination temperature was confirmed oddly to have a significant effect on the morphology, the textural properties and the surface chemistry of manganese oxides. Both the pristine amorphous MnO2 and the one calcined at 300 °C (MnO2-300) exhibited superior catalytic activity for ozone decomposition owing to the abundant surface oxygen vacancies, large specific surface area, and high oxygen mobility, which were derived from the amorphous structure. FTIR and in situ DRIFTS experiments revealed that calcination generated the hydrophobic MnO2-300, which showed enhanced water resistant ability compared with the pristine amorphous MnO2, and significantly suspended catalyst deactivation. Moreover, the oxidation state of Mn slightly changed in the used MnO2-300, further maintaining the high activity. This work may broaden the horizons of designing catalysts with high stability and efficiency for ozone decomposition.
研究领域:
环境科学
·
催化化学
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2021
·
IF 9.028
Honglong Zhang,Zhenyu Shi,Ruopeng Bai,Dingxiang Wang,Fuyi Cui,Jing Zhang,Timothy J. Strathmann
Permanganate (Mn(VII)) has been widely applied as an oxidant in water treatment plants. However, compared with ozone, Fenton, and other advanced oxidation processes, the reaction rates of some trace organic contaminants (TrOCs) with Mn(VII) are relatively low. Therefore, further studies on the strategies for enhancing the oxidation of organic contaminants by Mn(VII) are valuable. In this work, 2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPO), as an electron shuttle, enhanced Mn(VII) oxidation toward various TrOCs (i.e., bisphenol A (BPA), phenol, estrone, sulfisoxazole, etc.). TEMPO sped up the oxidative kinetics of BPA by Mn(VII) greatly, and this enhancement was observed at a wide pH range of 4.0–11.0. The exact mechanism of TEMPO in Mn(VII) oxidation was described briefly as follows: (i) TEMPO was oxidized by Mn(VII) to its oxoammonium cation (TEMPO+) by electron transfer, which was the reactive species responsible for the accelerated degradation of TrOCs and (ii) TEMPO+ could decompose TrOCs rapidly with itself back to TEMPO or TEMPOH (TEMPO hydroxylamine). To further illustrate the interaction between TEMPO and target TrOCs, we explored the transformation pathways of BPA in Mn(VII)/TEMPO oxidation. Compared to Mn(VII) alone, adding TEMPO into the Mn(VII) solution significantly suppressed BPA’s self-coupling and promoted hydroxylation, ring-opening, and decarboxylation. Moreover, the Mn(VII)/TEMPO system was promising for the abatement of TrOCs in real waters for humic acid, and ubiquitous cations/anions had no adverse or even beneficial impact on the Mn(VII)/TEMPO system.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
PubMed
高影响因子
BIOMATERIALS
·
2018
·
IF 8.806
Ruixue Song,Meng Zhang,Yanyan Liu,Zhaowen Cui,Hua Zhang,Zhongmin Tang,Xiaoyan Chen,Haihong Wu,Zhenwei Yao,Mingyuan He,Wenbo Bu
Hypoxia, as an inevitable characteristic of solid tumors, has been regarded as a noticeably causative factor to therapeutic resistance and metastatic variants. Exploring novel theranostics to realize the accurate diagnosis of hypoxia and the simultaneous implementation of effective therapy is a promising prospect for the successful treatment of tumors. In the present study, we designed and synthesized a multifunctional rattle-structured nanotheranostic, with the inner core coated by hollow mesoporous silica for chemical drug Doxorubicin (DOX) storage and hypoxia-sensitive MnO 2 enrichment. In various acidic micro-environments caused by hypoxia, MnO 2 nanosheets could be degraded into manganese ions (Mn 2+ ), which were chelated by the modified Tetraxetanum (DOTA) ligands for real-time T 1 -magnetic resonance imaging (T 1 -MRI), with on-demand DOX release to realize both normoxia and hypoxia-sensitive chemotherapy by overcoming hypoxia. Nanotheranostics integrating hypoxia-driven T 1 -MRI with synergetic chemotherapy have tremendous potential in the intelligent diagnosis, personalized treatment and excellent prognosis of solid tumors in the future.
研究领域:
医学影像学
·
肿瘤学
·
纳米医学
✓ 已验证
DOI
PubMed
高影响因子
Journal of Cleaner Production
·
2021
·
IF 9.297
Jing Su,Tao Lyu,Mick Cooper,Robert J.G. Mortimer,Gang Pan
Arsenic (As) is a toxic contaminant in surface waters and groundwater. Oxidation of arsenite (As(III)) to less toxic arsenate (As(V)) by hydrogen peroxide (H 2 O 2 ) is desirable for enhancing the immobilisation of Arsenic (As). However, this As(III) oxidation process is constrained by the strong pH dependence and the generated As(V) must also be removed for complete As remediation. This study developed and evaluated a novel heterogeneous catalytic system using manganese-doped Lanthanum oxycarbonate (MnL) to catalyse the oxidation of As(III) by H 2 O 2 and simultaneously adsorb the generated As(V). The presence of MnL enhanced the removal rate of As(III) by 35 times compared with systems utilising H 2 O 2 alone. Additionally, this superior performance was observed over a wide pH range (5–9), which demonstrated this approach could bypass the well-known pH restriction on oxidation by H 2 O 2 . Mechanistic studies revealed that the long-lived superoxide radicals (·O 2 − /·OOH), present on the particle surfaces and derived from the dissociation of the Lewis acid-base adduct (La–OOH*), were the dominant active species for As(III) oxidation. Mn atoms with low valence states played a crucial role in As(III) oxidation through the provision of extra active sites to facilitate radical production. The La and Mn sites in MnL could rapidly immobilize the generated As(V) by forming precipitates, resulting in a final As removal efficiency of 99% even after three cycles of reutilisation. Overall, this study demonstrates the viability of the proposed novel multi-functional catalyst for efficient As remediation from aqueous environments .
研究领域:
环境科学
·
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Zhuoyao Fang,Siyuan Pan,Xiaolin Zhang,Lu Lv,Bingcai Pan
Efficient removal of As(III) from groundwater remains an urgent but still challenging task. The X-Mn (X = Fe, Zr, Al…) binary oxide nanoparticles enable simultaneous oxidation and sequestration of As(III), yet facing the challenges in facile synthesis of the ultra-small nanoparticles with extraordinary decontamination reactivity, and in effective regeneration of oxidation capability. Herein, we prepared a novel nanocomposite Zr-Mn@N201 by conducting stepwise precipitation of hydrated oxides of zirconium (HZO) and manganese (HMO) inside the commercial gel-type anion exchanger N201, i.e. , the quaternary ammoniated poly(styrene-co-divinylbenzene) bead. Owing to restriction of nanopores, the HZO/HMO inside N201 possessed an ultra-small size around 4.78 nm. The kinetics and spectroscopic results suggested that As(III) was transformed into As(V) by HMO prior to adsorption onto HZO, and the negatively charged HMO captured most of the produced Mn 2+ ions. Alkaline treatment could regenerate Zr-Mn@N201 through simultaneously desorbing As(V) and transforming Mn 2+ into HMO again. During a 10-cyclic adsorption-regeneration assay, Zr-Mn@N201 could steadily reduce As(III) from 500 μg/L to < 10 μg/L with negligible HMO loss (<0.3%) in each run. In fixed-bed assays, the integration of HMO increased the effective treatment amounts of the Zr-Mn@N201 column toward the realistic groundwater by ∼ 11.5 times over the single nano-HZO ( i.e. , HZO@N201) column, reaching to ∼ 4600 bed volume with < 1% HMO loss.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2019
·
IF 3.45
Xueyun Liu,Cuimei Cheng,Na Zeng,Xiaoman Li,Qing Jiao,Changgui Lin,Shixun Dai
In comparison to narrow-band upconversion (UC) luminescence from lanthanide-doped systems, broadband UC emission enables a broad and tailorable emissive color, which is desirable for tunable lasers and multicolor display applications. Herein, dual continuous broadband UC emission covering the visible spectral region at 480–720 nm has been achieved for the first time in Yb 3+ /Mn 2+ co-doped glass ceramics (GCs) functionalized with the precipitation of dual-phase γ -Ga 2 O 3 / β -YF 3 nanocrystals . A tunable UC emissive color from yellowish to orange could be obtained under 980 nm excitation by varying the Mn 2+ doping content and heat treatment temperature of GCs. We ascribe this phenomenon to the typical transition of exchange-coupled Yb 3+ -Mn 2+ dimers in tetrahedral and octahedral ligand environments. The Stokes and power-dependent UC luminescence properties, fluorescence lifetimes, site occupation and the involved UC mechanism are discussed in detail. This research contributes to a better understanding of the UC process between Yb 3+ and Mn 2+ in transparent hosts and provides a novel perspective for designing broadband-emitting UC materials.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
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 .
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2024
·Vol. 35
·期 29
·1-12
·
IF 2.8
Zhang Zeqing,Liu Wei,Li Lin,Li Huan,Zhang Zhijun,Cheng Shuai,Rao Guanghui,Zhao Jingtai
In recent years, materials exhibiting multimodal luminescence properties from deep red to near-infrared (NIR) wavelengths have been a focal point of research, particularly in the exploration of applications within the realms of stress sensing and dynamic signature anti-counterfeiting. A pyroxene-type layered crystal structure compound, CaMgGe 2 O 6 : Mn 2+ , has been reported as a mechanoluminescent (ML) material. Upon incorporation into the host, Mn 2+ ions preferentially substitute for Mg 2+ ions, emitting deep red to near-infrared light (600–800 nm) within this six-coordinated [MgO 6 ] octahedral environment. The congruence of photoluminescence and ML spectra indicates that both types of luminescence originate from the same emissive center. The doping of Mn 2+ ions introduces impurity band, effectively reducing the optical band gap, as evidenced by ultraviolet diffuse reflectance measurements. Thermoluminescence results reveal three defect centers within the phosphor, whose concentrations decrease with Mn 2+ doping, correlating with a reduction in ML intensity. The ML mechanism of the phosphor is elucidated through the analysis of local piezoelectric properties within the crystal. Overall, this study may pave new pathways for the development of efficient near-infrared mechanoluminescent materials, showcasing potential applications within the biological domain.
研究领域:
材料科学
·
光学
·
生物医学工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）