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1.
Article in English | MEDLINE | ID: mdl-38686340

ABSTRACT

Purpose: This study determined the digital mammography and ultrasonography imaging features of pure invasive micropapillary carcinoma of the breast (PIMPC) and the correlation with pathologic features. Patients Methods: Nineteen patients diagnosed with PIMPC at Yantaishan Hospital from October 2015 to February 2022 were included in the study group. Forty patients with breast masses diagnosed as nonspecific invasive ductal carcinoma of the breast (NIDC) from July to December 2021 were included in the control group. Digital mammography and ultrasonography features were compared between the two groups. Results: Patients with PIMPC had a younger age profile compared to patients with NIDC (P=0.017). Moreover, PIMPC masses were smaller than NIDC masses (P=0.040). Imaging features analysis revealed significant differences in age groups (<45 years: χ²=5.971, P=0.044) and the presence of spiculations or the crab claw sign (χ²=8.583, P=0.004) between patients with PIMPC and NIDC. However, there were no statistically significant differences in the presence of calcifications, blood flow grading, pathologic molecular subtypes between the study and control groups. The Ki-67 proliferative index (χ²=1.052, P=0.389), vascular invasion (χ²=2.263, P=0.197), and lymph node metastasis (χ²=1.968, P=0.386) showed no significant differences between PIMPC and NIDC patients. Conclusion: PIMPC imaging features show specificity, such as tiny breast masses, spiculated edges, or crab claw-like patterns, and malignant signs appeared when the lesion was <2 cm in diameter. PIMPC mainly occurs in middle-aged women 45-59 y of age. Patients with PIMPC and NIDC of the breast are frequently associated with lymph node metastases and greater than one-half of the cases (74%) were shown to have a Ki-67 index >30%, suggesting a significant risk of recurrence and metastasis. Early therapeutic care for these patients is crucial. These results warrant further validation with additional samples from several centers due to the limited single-center sample size in the current study.

2.
Adv Mater ; 36(23): e2400177, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38346222

ABSTRACT

As next-generation energy storage devices, lithium metal batteries (LMBs) must offer high safety, high-voltage resistance, and a long life span. Electrolyte engineering is a facile strategy to tailor the interfacial chemistry of LMBs. In particular, the solvation structure and derived solid electrolyte interphase (SEI) are crucial for a satisfactory battery performance. Herein, a novel middle-concentrated ionic liquid electrolyte (MCILE) with an anion-rich solvation structure tuned by difluorinated cations is demonstrated to achieve ultrahigh safety, high-voltage stability, and excellent ternary-cathode compatibility. Novel gem-difluorinated cations first synthesized for prestoring fluorine on positively charged species, not only preferentially adsorb in the inner-Helmholtz layers, but also participate in regulating the Li+ solvation structure, resulting in a robust interphase. Moreover, these weak interactions in the Li+ solvation structure including anion-solvent and ionic liquid (IL) cation-solvent pairs are first revealed, which are beneficial for promoting an anion-dominated solvation structure and the desolvation process. Benefiting from the unique anion-rich solvation structure, a stable hetero-SEI structure is obtained. The designed MCILE exhibits compatibility with Li metal anode and the high-voltage ternary cathode at high temperatures (60 °C). This work provides a new approach for regulating the solvation structure and electrode interphase chemistry of LMBs via difluorinated IL cations.

3.
Angew Chem Int Ed Engl ; 63(8): e202317148, 2024 Feb 19.
Article in English | MEDLINE | ID: mdl-38169131

ABSTRACT

Stabilizing electrolytes for high-voltage lithium metal batteries (LMBs) is crucial yet challenging, as they need to ensure stability against both Li anodes and high-voltage cathodes (above 4.5 V versus Li/Li+ ), addressing issues like poor cycling and thermal runaway. Herein, a novel gem-difluorinated skeleton of ionic liquid (IL) is designed and synthesized, and its non-flammable electrolytes successfully overcome aforementioned challenges. By creatively using dual salts, fluorinated ionic liquid and dimethyl carbonate as a co-solvent, the solvation structure of Li+ ions is efficiently controlled through electrostatic and weak interactions that are well unveiled and illuminated via nuclear magnetic resonance spectra. The as-prepared electrolytes exhibit high security avoiding thermal runaway and show excellent compatibility with high-voltage cathodes. Besides, the solvation structure derives a robust and stable F-rich interphase, resulting in high reversibility and Li-dendrite prevention. LiNi0.6 Co0.2 Mn0.2 O2 /Li LMBs (4.5 V) demonstrate excellent long-term stability with a high average Coulombic efficiency (CE) of at least 99.99 % and a good capacity retention of 90.4 % over 300 cycles, even can work at a higher voltage of 4.7 V. Furthermore, the ultrahigh Ni-rich LiNi0.88 Co0.09 Mn0.03 O2 /Li system also delivers excellent electrochemical performance, highlighting the significance of fluorinated IL-based electrolyte design and enhanced interphasial chemistry in improving battery performance.

4.
Adv Mater ; 35(39): e2305945, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37450565

ABSTRACT

Fe-N-C catalyst for oxygen reduction reaction (ORR) has been considered as the most promising nonprecious metal catalyst due to its comparable catalytic performance to Pt in proton exchange membrane fuel cells (PEMFCs). The active centers of Fe-pyrrolic N4 have been proven to be extremely active for ORR. However, forming a stable Fe-pyrrolic N4 structure is a huge challenge. Here, a Cyan-Fe-N-C catalyst with Fe-pyrrolic N4 as the intrinsic active center is constructed with the help of axial Fe4 C atomic clusters, which shows a half-wave potential of up to 0.836 V (vs. RHE) in the acid environment. More remarkably, it delivers a high power density of 870 and 478 mW cm-2 at 1.0 bar in H2 -O2 and H2 -Air fuel cells, respectively. According to theoretical calculation and in situ spectroscopy, the axial Fe4 C can provide strong electronic perturbation to Fe-N4 active centers, leading to the d-orbital electron delocalization of Fe and forming the Fe-pyrrolic N4 bond with high charge distribution, which stabilizes the Fe-pyrrolic N4 structure and optimizes the OH* adsorption during the catalytic process. This work proposes a new strategy to adjust the electronic structure of single-atom catalysts based on the strong interaction between single atoms and atomic clusters.

5.
Small Methods ; 7(3): e2201524, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36642792

ABSTRACT

Atomically dispersed metal-nitrogen-carbon catalysts (M-N-C) have been widely used in the field of energy conversion, which has already attracted a huge amount of attention. Due to their unsaturated d-band electronic structure of the center atoms, M-N-C catalysts can be applied in different electrocatalytic reactions by adjusting their own microscopic electronic structures to achieve the optimization of the structure-activity relationship. Consequently, it is of great significance for the revelation of electrocatalytic mechanism and structure-activity relationship of M-N-C catalysts. Thus, this review first introduces the relative research methods, including in situ/operando characterization techniques and theoretical calculation methods. Furthermore, clarifying the electrocatalytic mechanism and structure-activity relationship of M-N-C catalysts in different electrochemical energy conversion reactions is focused. Moreover, the future research directions are pointed out based on the discussion. This review will provide good guidance to systematically study the catalytic mechanism of single-atom catalysts and reasonably design the single-atom catalysts.

6.
Small ; 19(5): e2205638, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36417556

ABSTRACT

Searching for high effective catalysts has been an endless effort to improve the efficiency of green energy harvesting and degradation of pollutants. In the past decades, tremendous strategies are explored to achieve high effective catalysts, and various theoretical understandings are proposed for the improved activity. As the catalytic reaction occurs at the surface or edge, the unsaturated ions may lead to the fluctuation of spin. Meanwhile, transition metals in catalysts have diverse spin states and may yield the spin effects. Therefore, the role of spin or magnetic moment should be carefully examined. In this review, the recent development of spin catalysts is discussed to give an insightful view on the origins for the improved catalytic activity. First, a brief introduction on the applications and advances in spin-related catalytic phenomena, is given, and then the fundamental principles of spin catalysts and magnetic fields-radical reactions are introduced in the second part. The spin-related catalytic performance reported in oxygen evolution/reduction reaction (OER/ORR) is systematically discussed in the third part, and general rules are summarized accordingly. Finally, the challenges and perspectives are given. This review may provide an insightful understanding of the microscopic mechanisms of catalytic phenomena and guide the design of spin-related catalysts.

7.
J Colloid Interface Sci ; 613: 276-284, 2022 May.
Article in English | MEDLINE | ID: mdl-35042028

ABSTRACT

Fabricating high-efficiency catalysts of Pt nanoparticles coupled with single-atom sites (MNC) attracts intensive attention to accelerate the oxygen reduction reaction (ORR). Here we rationally design the low-Pt hybrid catalyst containing fine Pt nanoparticles coupled with Co-Nx moieties via a microwave-assisted heating process. The well-dispersed Pt nanoparticles are anchored by CoNC supports because of the metal-support interaction. Furthermore, the Co-Nx moiety acts as an electron donor to regulate the electronic structure of Pt through the electron synergistic effect, moderating the adsorption energy of oxygen intermediates on Pt sites, and then increasing the intrinsic activity of Pt. In addition, the overflow effect from CoNC to Pt facilitates a nearly four-electron process and enhances the kinetics of ORR. In acid media, the optimized 10% Pt/CoNC hybrid catalysts with Pt nanoparticles size (2.18 nm) exhibit improved ORR activity and robust durability, delivering a half-wave potential (E1/2) of 0.886 V and negligible loss after accelerated durability test, exceeding the best-in-class commercial Pt/C. The finding of the synergy between CoNC supports and Pt nanoparticles offers a novel ideation to construct various low-loading Pt-based hybrid catalysts.


Subject(s)
Nanoparticles , Oxygen , Catalysis , Catalytic Domain
8.
Small Methods ; 5(6): e2100024, 2021 Jun.
Article in English | MEDLINE | ID: mdl-34927909

ABSTRACT

Mn and N codoped carbon materials are proposed as one of the most promising catalysts for the oxygen reduction reaction (ORR) but still confront a lot of challenges to replace Pt. Herein, a novel gas-phase migration strategy is developed for the scale synthesis of atomically dispersed Mn and N codoped carbon materials (g-SA-Mn) as highly effective ORR catalysts. Porous zeolitic imidazolate frameworks serve as the appropriate support for the trapping and anchoring of Mn-containing gaseous species and the synchronous high-temperature pyrolysis process results in the generation of atomically dispersed Mn-Nx active sites. Compared to the traditional liquid phase synthesis method, this unique strategy significantly increases the Mn loading and enables homogeneous dispersion of Mn atoms to promote the exposure of Mn-Nx active sites. The developed g-SA-Mn-900 catalyst exhibits excellent ORR performance in the alkaline media, including a high half-wave potential (0.90 V vs reversible hydrogen electrode), satisfactory durability, and good catalytic selectivity. In the practical application, the Zn-air battery assembled with g-SA-Mn-900 catalysts shows high power density and prominent durability during the discharge process, outperforming the commercial Pt/C benchmark. Such a gas-phase synthetic methodology offers an appealing and instructive guide for the logical synthesis of atomically dispersed catalysts.

9.
ACS Appl Mater Interfaces ; 13(44): 52542-52548, 2021 Nov 10.
Article in English | MEDLINE | ID: mdl-34714627

ABSTRACT

Heterostructures show great potential in energy storage due to their multipurpose structures and function. Recently, two-dimensional (2D) graphene has been widely regarded as an excellent substrate for active materials due to its large specific surface area and superior electrical conductivity. However, it is prone to self-aggregation during charging and discharging, which limits its electrochemical performance. To address the graphene agglomeration problem, we interspersed polypyrrole carbon nanotubes between the graphene cavities and designed three-dimensional (3D)-heterostructures of ZnMn2O4@rGO-polypyrrole carbon nanotubes (ZMO@G-PNTs), which demonstrated a high rate and cyclic stability in lithium-ion capacitors (LICs). Furthermore, the 3D porous structure provided more surface capacity contribution than 2D graphene, ultimately resulting in a better stability (333 mAh g-1 after 1000 cycles at 1 A g-1) and high rate capacity (208 mAh g-1 at 5 A g-1). Also, the mechanism of performance difference between ZMO@G-PNTs and ZMO@G was investigated in detail. Moreover, LICs built from ZMO@G-PNTs as an anode and activated carbon as a cathode showed an energy density of 149.3 Wh kg-1 and a power density of 15 kW kg-1 and cycling stability with a capacity retention of 61.5% after 9000 cycles.

10.
iScience ; 24(9): 103024, 2021 Sep 24.
Article in English | MEDLINE | ID: mdl-34585108

ABSTRACT

The sluggish oxygen reduction reaction (ORR) has becoming the bottleneck of largescale implementation of proton exchange membrane fuel cells. However, when it comes to the ORR activity assessing of platinum group metals (PGMs) with rotating disk electrode, the corresponding potential conversion vs. reversible hydrogen electrode, test protocols, and activity calculation processes are still in chaos in many published literatures. In this work, two standard calculation processes for PGM ORR activities are demonstrated, followed by a specification for the usage of reference electrodes. Then a 4-fold discrepancy in ORR activities obtained via different test protocols is found for the same Pt/C, and an average adsorption model and the "coverage effects" are proposed to illustrate the hysteresis loop between negative and positive-going ORR polarization plots. Finally, four motions over appropriate assessment of PGM ORR activity are emphasized, hoping to bring a fair communication platform for researchers from different groups.

11.
Ultrasound Q ; 37(1): 52-55, 2021 Mar 01.
Article in English | MEDLINE | ID: mdl-33661798

ABSTRACT

ABSTRACT: Mammary myofibroblastoma (MFB) is a rare benign stromal neoplasm; its imaging features are rarely reported and nonspecific. We retrospectively analyzed a case of pathologically proved breast MFB that revealed indistinct high-density mass in mammography and hypoechoic ill-defined breast tumor in ultrasonography. Meanwhile, hypointense appearance on T2-weighted imaging of magnetic resonance imaging and containing fat tissue might be very valuable characteristics in the differential diagnosis of breast MFB.


Subject(s)
Breast Neoplasms , Neoplasms, Muscle Tissue , Breast/diagnostic imaging , Breast Neoplasms/diagnostic imaging , Female , Humans , Mammography , Neoplasms, Muscle Tissue/diagnostic imaging , Retrospective Studies , Ultrasonography
12.
ACS Appl Mater Interfaces ; 12(49): 54773-54781, 2020 Dec 09.
Article in English | MEDLINE | ID: mdl-33226768

ABSTRACT

Potassium-ion capacitors (KICs) have received a surge of interest because of their higher reserves and lower costs of potassium than lithium. However, the cycle performance and capacity of potassium devices have been reported to be unsatisfactory. Herein, a unique crystalline MnCo2O4.5 and amorphous MnCo2S4 core/shell nanoscale flower structure grown on graphene (MCO@MCS@rGO) was synthesized by a two-step hydrothermal process and demonstrated in KICs. The MCO@MCS@rGO exhibits improved electrical conductivity and excellent structural integrity during the charging and discharging process. The reasons could be attributed to the cavity structure of MCO, the mechanical buffer and high electrolyte diffusion rate of MCS, and the auxiliary effect of graphene. The electrical conductivity of MCO@MCS shows a specific capacity of 272.3 mA h g-1 after 400 cycles at 1 A g-1 and a capacity of 125.6 mA h g-1 at 2 A g-1. Besides, the MCO@MCS@rGO and high-surface-area activated carbon in KICs exhibit a relative energy density of 85.3 W h kg-1 and a power density of 9000 W kg-1 and outstanding cycling stability with a capacity retention of 76.6% after 5000 cycles. Moreover, the reaction mechanism of MCO@MCS@rGO in the K-ion cell was investigated systematically using X-ray diffraction and transmission electron microscopy, providing guidance on the further development of pseudocapacitive materials.

13.
ACS Nano ; 14(10): 13765-13774, 2020 Oct 27.
Article in English | MEDLINE | ID: mdl-33025784

ABSTRACT

Sluggish kinetics and limited reversible capacity present two major challenges for layered titanates to achieve satisfactory sodium-ion storage performance at subzero-temperatures (subzero-T). To facilitate sodiation dynamics and improve reversible capacity, we proposed an additive-free anode with Sn(II) located between layers. Sn-5s in interlayer-confining Sn(II), which has a larger negative charge, will hybridize with O-2p to trigger charge redistribution, thereby enhancing electronic conductivity. H-titanates with an open framework are designed to stabilize Sn(II) and restrain subsequent volume expansion, which could potentially surpass the capacity limitation of titanate-based materials via a joint alloying-intercalation reaction with high reversibility. Moreover, the generation of conductive Na14Sn4 and the expansion of interlayer spacing resulting from the interlayered alloying reaction are beneficial for charge transfer. These effects synergistically endow the modified sample with a considerably lower activation energy and a 3-fold increase in diffusion. Consequently, the designed anode delivers excellent subzero-T adaptability when compared to the unmodified sample, maintaining capacity retention of 91% after 1200 cycles at -20 °C and 90% after 850 cycles at -30 °C.

14.
Nanoscale ; 12(42): 21534-21559, 2020 Nov 05.
Article in English | MEDLINE | ID: mdl-33112936

ABSTRACT

The catalyst in the oxygen electrode is the core component of the aqueous metal-air battery, which plays a vital role in the determination of the open circuit potential, energy density, and cycle life of the battery. For rechargeable aqueous metal-air batteries, the catalyst should have both good oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) catalytic performance. Compared with precious metal catalysts, non-precious metal materials have more advantages in terms of abundant resource reserves and low prices. Over the past few years, great efforts have been made in the development of non-precious metal bifunctional catalysts. This review selectively evaluates the advantages, disadvantages and development status of recent advanced materials including pure carbon materials, carbon-based metal materials and carbon-free materials as bifunctional oxygen catalysts. Preliminary improvement strategies are formulated to make up for the deficiency of each material. The development prospects and challenges facing bifunctional catalysts in the future are also discussed.

15.
Nanoscale ; 12(2): 973-982, 2020 Jan 02.
Article in English | MEDLINE | ID: mdl-31840721

ABSTRACT

Non-noble metal materials are regarded as the most promising catalysts for the oxygen reduction reaction (ORR) to overcome the inherent defects of Pt-based catalysts, like high cost, limited availability and insufficient stability. Here, we fabricate sandwich-like Co encapsulated nitrogen doped carbon polyhedron/graphene (s-Co@NCP/rGO) via a facile and scalable strategy by loading Co-based zeolitic imidazolate framework (ZIF-67) and graphene oxide (GO) layers individually on a polyurethane (PU) sponge template. The 3D sandwich structure is maintained with the assistance of the sponge template, which promotes the uniform dispersion of ZIF-67-derived Co embedded nitrogen doped carbon polyhedra (Co@NCP) and prevents the graphene plates from agglomerating during the annealing process. The final product demonstrates considerable catalytic performance for the ORR with a half-wave potential of 0.85 V, preferable stability and increased poisoning tolerance by comparison to 20 wt% Pt/C, which stems from the 3D sandwich-like structure, N/Co-doping effect, large accessible surface area and hierarchical porous structures. The excellent ORR performance of the catalysts means that they can be utilised in a Zn-air battery as cathode catalysts. During such a demonstration, s-Co@NCP/rGO shows a high open-circuit voltage of 1.466 V, remarkable long-term durability and an outstanding peak power density of 186 mV cm-2, which shows its high potential as a prospective alternative for widespread practical application in the field of non-noble metal ORR catalysts.

16.
J Colloid Interface Sci ; 542: 177-186, 2019 Apr 15.
Article in English | MEDLINE | ID: mdl-30738310

ABSTRACT

A novel composite vanadium-blocking proton exchange membrane for vanadium redox flow battery (VRB) was designed and constructed by immobilizing phosphotungstic acid (PWA) on Nano Kevlar Fibers (NKFs) via a solution-casting method. The proton/vanadium selectivity of the composite membrane is greatly improved by incorporating the complex formed by NKFs and PWA into the Nafion matrix. Simple tuning of the complex doping quantity results in different composite membranes with superior vanadium barrier properties (namely, a minimum vanadium permeability of 2.46 × 10-7 cm2 min-1). This coupled with proton conductivities reaching 0.061 S cm-1 at room temperature indicates a proton/vanadium selectivity of 2.48 × 105 S min cm-3, which is 6.3 times higher than that of recast Nafion (0.34 × 105 S min cm-3). When tested in a VRB, the performance of the single cell assembled with the composite membrane greatly outperforms that with recast Nafion at current densities ranging from 40 to 100 mA cm-2.

17.
Chem Asian J ; 13(20): 3057-3062, 2018 Oct 18.
Article in English | MEDLINE | ID: mdl-30133158

ABSTRACT

The oxygen reduction reaction (ORR) in a cathode is an essential component of many electrochemical energy storage and conversion systems. Two-dimensional materials are beneficial for electron conduction and mass transport with high density, showing prominent electrochemical catalytic performance towards the ORR. Herein, a simple NaCl-assisted method to synthesize cobalt-nitrogen-doped carbon materials (CoNC), which present prominent performance towards the ORR in alkaline media, is described. The utilization of the NaCl template endows the product with a large specific surface area of 556.4 m2 g-1 , as well as good dispersion of cobalt nanoparticles. CoNC-800@NaCl (800 indicates the calcination temperature in °C) displays an excellent onset potential of 0.94 V (vs. a reversible hydrogen electrode), which is close to that of commercial Pt/C. Additionally, CoNC-800@NaCl also exhibits better long-term durability and methanol tolerance than that of Pt/C. The high-performance CoNC-800@NaCl catalyst provides a hopeful alternative to noble-metal catalysts for the ORR in practical applications.

18.
ACS Appl Mater Interfaces ; 8(25): 16026-34, 2016 Jun 29.
Article in English | MEDLINE | ID: mdl-27266527

ABSTRACT

Three-dimensional hierarchical nitrogen-doped graphene (3D-NG) frameworks were successfully fabricated through a feasible solution dip-coating method with commercially available sponges as the initial backbone. A spongy template can help hinder the graphene plates restacking in the period of the annealing process. The Pt/3D-NG catalyst was synthesized employing a polyol reduction process. The resultant Pt/3D-NG exhibits 2.3 times higher activity for methanol electro-oxidation along with the improvement in stability as compared with Pt/G owing to their favorable features including large specific surface area, high pore volume, high N doping level, and the homogeneous dispersion of Pt nanoparticles. Besides, Pt/3D-NG also presents high oxygen reduction reaction (ORR) performance in acid media when compared with Pt/3D-G and Pt/G. This work raises a valid solution for the fabrication of 3D functional freestanding graphene-based composites for a variety of applications in fuel cell catalysis, energy storage, and conversion.

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