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1.
Adv Mater ; : e2405906, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38943439

RESUMO

Deep-sea equipment usually operates under dwell-fatigue condition, which means the equipped energy storage devices must survive under the changing pressure. Special mechanical designs should be considered to maintain the electrochemical performance of electrodes under this extreme condition. In this work, an effective assembly strategy is proposed to accommodate the dwell-fatigue loading using Ag decorated reduced graphene oxide (rGO) foam (denoted as AGF) as a superelastic and robust Zn host. The wet-press assembly process enables the formation of highly porous and robust framework. The strong synergetic effect between rGO and Ag further guarantees AGF's superelasticity and ultrahigh mechanical strength. Meanwhile, the homogeneously distributed Ag species on the rGO sheets act as zincophilic sites to effectively facilitate Zn plating. Furthermore, AGF offers enough space to address the expansion during the charge and discharge cycles. As expected, the symmetrical cell using this AGF@Zn host demonstrates a long lifespan over 400 h at a depth-of-discharge of 50%. It is worth mentioning that the superelastic AGF host realizes stable Zn plating/stripping under varying pressures.

2.
Angew Chem Int Ed Engl ; 62(51): e202315257, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-37930152

RESUMO

Layered manganese dioxide is a promising cathode candidate for aqueous Zn-ion batteries. However, the narrow interlayer spacing, inferior intrinsic electronic conductivity and poor structural stability still limit its practical application. Herein, we report a two-step strategy to incorporate ammonium ions into manganese dioxide (named as AMO) nanosheets as a cathode for boosted Zn ion storage. K+ -intercalated δ-MnO2 nanosheets (KMO) grown on carbon cloth are chosen as the self-involved precursor. Of note, ammonium ions could replace K+ ions via a facile hydrothermal reaction to enlarge the lattice space and form hydrogen-bond networks. Compared with KMO, the structural stability and the ion transfer kinetics of the layered AMO are enhanced. As expected, the obtained AMO cathode exhibits remarkable electrochemical properties in terms of high reversible capacity, decent rate performance and superior cycling stability over 10000 cycles.

3.
Small ; 19(38): e2301523, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37194981

RESUMO

Lithium (Li) metal anode (LMA) is highly considered as a desirable anode material for next-generation rechargeable batteries because of its high specific capacity and the lowest reduction potential. However, uncontrollable growth of Li dendrites, large volume change, and unstable interfaces between LMA and electrolyte hinder its practical application. Herein, a novel in situ formed artificial gradient composite solid electrolyte interphase (GCSEI) layer for highly stable LMAs is proposed. The inner rigid inorganics (Li2 S and LiF) with high Li+ ion affinity and high electron tunneling barrier are beneficial to achieve homogeneous Li plating, while the flexible polymers (poly(ethylene oxide) and poly(vinylidene fluoride)) on the surface of GCSEI layer can accommodate the volume change. Furthermore, the GCSEI layer demonstrates fast Li+ ion transport capability and increased Li+ ion diffusion kinetics. Accordingly, the modified LMA enables excellent cycling stability (over 1000 h at 3 mA cm-2 ) in the symmetric cell using carbonate electrolyte, and the corresponding Li-GCSEI||LiNi0.8 Co0.1 Mn0.1 O2 full cell demonstrates 83.4% capacity retention after 500 cycles. This work offers a new strategy for the design of dendrite-free LMAs for practical applications.

4.
Angew Chem Int Ed Engl ; 61(49): e202213049, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36218244

RESUMO

The exploration of earth-abundant and efficient electrocatalysts toward the oxygen evolution reaction (OER) is critical for sustainable energy storage and conversion devices. In this work, we report a self-engaged strategy to fabricate a yolk-shelled OER electrocatalyst. Starting with a metal-organic framework, Co-Fe layered double hydroxide (LDH)@zeolitic imidazolate framework-67 (ZIF-67) yolk-shelled structures are formed in one step. Afterwards, these ZIF-67 building blocks are transformed into Ni-Co LDH nanocages to form the Ni-Co-Fe hydr(oxy)oxide@Ni-Co LDH yolk-shelled microrods (NiCoFe-HO@NiCo-LDH YSMRs) through an ion-exchange reaction. Owing to the structural and compositional merits, the NiCoFe-HO@NiCo-LDH YSMR electrocatalyst exhibits an overpotential of 278 mV to reach the current density of 10 mA cm-2 , a small Tafel slope of 49.7 mV dec-1 , and good stability in alkaline media.

5.
Chem Commun (Camb) ; 58(78): 10973-10976, 2022 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-36093782

RESUMO

A ternary-salt solid polymer electrolyte (TS-SPE) consisting of LiPF6-LiTFSI-LiFSI salts and poly(1,3-dioxolane) is created by in situ polymerization. The TS-SPE possesses high ionic conductivity, high Li+ ion transference number, and stable SEI with low interfacial impedance, thereby realizing excellent rate performance and long-life stability in Li metal batteries.

6.
Small ; 18(30): e2203231, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35770812

RESUMO

Aqueous Zn metal batteries (AZMBs) have been considered as a promising alternative to the existing Li-ion batteries. Nevertheless, the large-scale application of the AZMBs is restricted by the dendrite formation and side reactions within the Zn metal anodes (ZMAs) during cycling. Herein, an atomically dispersed Cu in leaf-like Zn-coordinated zeolitic imidazolate framework (ZIF-L) nanoflakes on Ti mesh (CuZIF-L@TM) as ZMA host is developed. The 3D conductive network formed by the interconnected ZIF-L nanoflakes can reduce the local current density and homogenize the electric field distribution. Moreover, experimental data and theoretical calculations reveal the Cu single atoms within the ZIF-L can serve as the zincophilic sites to facilitate the Zn deposition. As expected, the CuZIF-L@TM host enables a homogeneous Zn deposition on the surface without dendrites. The resultant CuZIF-L@TM/Zn electrode shows stable Zn plating/stripping over 1100 h at 1 mA cm-2 with a low voltage hysteresis of about 50 mV. As a proof of concept, a full cell based on the designed CuZIF-L@TM/Zn anode shows a stable cycling performance over 1000 cycles.

7.
Chem Asian J ; 17(14): e202200178, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35438831

RESUMO

Water splitting driven by renewable energy sources is an environmentally friendly and sustainable way to produce hydrogen as an ideal energy source in the future. Electrocatalysts can promote the water splitting performance at the both ends. Therefore, the design of cost-effective, high-performance electrocatalysis is a key factor in promoting water decomposition and renewable energy conversion. Among candidates, layered molybdenum disulfide (MoS2 ) is considered as a most promising electrocatalyst to replace Pt for hydrogen evolution reaction (HER). Surface atomic engineering and interface engineering can induce new physicochemical properties for MoS2 to greatly enhance HER activity. In this report, we summarize the latest improvement strategies and research progress to improve the catalytic activity of MoS2 -based material catalysts through the surface and interface atomic and molecular engineering, thus effectively improving HER process. In addition, some unsolved problems in the large-scale application of modified MoS2 catalyst are also discussed.

8.
Sci Adv ; 8(10): eabm5766, 2022 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-35275713

RESUMO

We developed a three-dimensional hybrid fiber host consisting of interconnected N-doped hollow carbon spheres embedded with Sn nanoparticles (denoted as Sn@NHCF) for Zn metal anodes in high-performance Zn metal batteries. Experimental observations and density functional theory calculation reveal that the zincophilic Sn nanoparticles and N-doped carbons enable the homogeneous Zn deposition on the interior and exterior surfaces of the hollow fibers. Moreover, the hierarchical hollow fiber network effectively reduces the structural stress during the plating/stripping process. As a result, the developed Sn@NHCF host exhibits remarkable electrochemical properties in terms of high Coulombic efficiency, low voltage hysteresis, and prolonged cycling stability without dendrite formation. Moreover, a full cell based on the designed Sn@NHCF-Zn composite anode and a V2O5 cathode demonstrates superior rate capability and stable cycle life. This work provides a new strategy for the design of dendrite-free Zn anodes for practical applications.

9.
Chem Rec ; 22(10): e202100294, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35138030

RESUMO

Rechargeable batteries and supercapacitors are currently considered as promising electrochemical energy storage (EES) systems to address the energy and environment issues. Self-supported transition metal (Ni, Co, Mn, Mo, Cu, V)-based materials are promising electrodes for EES devices, which offer highly efficient charge transfer kinetics. This review summarizes the latest development of transition metal-based materials with self-supported structures for EES systems. Special focus has been taken on the synthetic methods, the selection of substrates, architectures and chemical compositions of different self-supported nanoarrays in energy storage systems. Finally, the challenges and opportunities of these materials for future development in this field are briefly discussed. We believe that the advancement in self-supported electrode materials would pave the way towards next-generation EES.

10.
Small ; 18(16): e2107890, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35218315

RESUMO

Layered titanates are of great potential for hybrid Na-ion capacitors (NICs). However, the poor conductivity and sluggish reaction kinetics are the critical issues for the practical applications of titanates. Herein, an approach to synthesize magnesium titanate hierarchical hollow spheres embedded in carbon nanofibers (denoted as MTO@C) by electrospinning coupled with interlayer engineering processes is reported. 3D conductive carbon framework helps to enhance the electronic conductivity for binder-free electrode, while the expanded interlayer spacing of titanate hierarchical hollow spheres via the incorporation of Mg2+ ions help to reduce the charge transfer resistance and expose more active sites for Na storage. The interconnected hollow spheres can effectively accommodate the volume expansion during the repeated cycles. The results have shown that the MTO@C electrode can deliver a high capacity of 136 mAh g-1 at 1 A g-1 with long lifespan. The assembled NIC device with MTO@C as anode and active carbon as cathode produces a high energy density of 110.3 Wh kg-1 at 112 W kg-1 and a high power density of 5380 W kg-1 at 41.9 Wh kg-1 , together with a high capacity retention of 80% after 5000 cycles.

11.
Adv Sci (Weinh) ; 9(9): e2105135, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35043604

RESUMO

Electrocatalytic water splitting using renewable energy is widely considered as a clean and sustainable way to produce hydrogen as an ideal energy fuel for the future. Electrocatalysts are indispensable elements for large-scale water electrolysis, which can efficiently accelerate electrochemical reactions occurring at both ends. Benefitting from high specific surface area, well-defined void space, and tunable chemical compositions, hollow nanostructures can be applied as promising candidates of direct electrocatalysts or supports for loading internal or external electrocatalysts. Herein, some recent progress in the structural design of micro-/nanostructured hollow materials as advanced electrocatalysts for water splitting is summarized. First, the design principles and corresponding strategies toward highly effective hollow electrocatalysts for oxygen/hydrogen evolution reactions are highlighted. Afterward, an overview of current reports about hollow electrocatalysts with diverse architectural designs and functionalities is given, including direct hollow electrocatalysts with single-shelled, multi-shelled, or open features and heterostructured electrocatalysts based on hollow hosts. Finally, some future research directions of hollow electrocatalysts for water splitting are discussed based on personal perspectives.

12.
Angew Chem Int Ed Engl ; 61(7): e202115649, 2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-34913229

RESUMO

Uncontrolled growth of Zn dendrites and side reactions are the major restrictions for the commercialization of Zn metal anodes. Herein, we develop a TiOx /Zn/N-doped carbon inverse opal (denoted as TZNC IO) host to regulate the Zn deposition. Amorphous TiOx and Zn/N-doped carbon can serve as the zincophilic nucleation sites to prevent the parasitic reactions. More importantly, the highly ordered IO host homogenizes the local current density and electric field to stabilize Zn deposition. Furthermore, the three-dimensional open networks could regulate Zn ion flux to enable stable cycling performance at large current densities. Owing to the abundant zincophilic sites and the open structure, granular Zn deposits could be realized. As expected, the TZNC IO host guarantees the steady Zn plating/stripping with a long-term stability over 450 h at the current density of 1 mA cm-2 . As a proof-of-concept demonstration, a TZNC@Zn||V2 O5 full cell shows long lifespan over 2000 cycles at 5.0 A g-1 .

13.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-936308

RESUMO

OBJECTIVE@#To evaluate the early and mid-term clinical results of medial parapatellar soft tissue overlapping suture in total knee arthroplasty for treatment of severe osteoarthritis combined with permanent patellar dislocation.@*METHODS@#We retrospectively analyzed the data of 12 patients (12 knees) diagnosed with severe knee osteoarthritis combined with permanent patellar dislocation undergoing total knee arthroplasty with medial parapatellar soft tissue overlapping suture. Knee Society Score (KSS), University of California Los Angeles (UCLA) activity-level rating, Visual Analog Scale (VAS) pain score, and knee range of motion of the patients were assessed before and 2 years after the surgery. Anteroposterior and lateral radiographs of the knee joint, full-length standing radiographs of the lower limbs and patellar axial radiographs were evaluated.@*RESULTS@#The mean Knee Society Score of the patients increased from 34.2±11.1 before surgery to 73.5±6.3 at two years after the surgery (P < 0.001). The UCLA activity-level rating increased from an average of 3.8 ± 0.8 before surgery to 5.8 ± 0.6 at two years postoperatively (P=0.003). The mean VAS pain score decreased from 42.8±6.0 before surgery to 20.1±3.7 (P < 0.001) and the range of motion of the knee joint increased from 74.6±8.9 degrees to 97.5±4.5 degrees at two years (P < 0.001). The radiographs showed no signs of subluxation or dislocation of the patella in all the patients.@*CONCLUSIONS@#Medial parapatellar soft tissue overlapping suture in total knee arthroplasty can achieve good early and mid-term clinical results for treatment of severe osteoarthritis combined with permanent patellar dislocation.


Assuntos
Humanos , Artroplastia do Joelho/métodos , Osteoartrite do Joelho/cirurgia , Patela/cirurgia , Estudos Retrospectivos , Suturas
14.
Acta Pharmaceutica Sinica B ; (6): 3103-3112, 2022.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-939952

RESUMO

Our previous study demonstrated that phosphodiesterase 8 (PDE8) could work as a potential target for vascular dementia (VaD) using a chemical probe 3a. However, compound 3a is a chiral compound which was obtained by chiral resolution on HPLC, restricting its usage in clinic. Herein, a series of non-chiral 9-benzyl-2-chloro-adenine derivatives were discovered as novel PDE8 inhibitors. Lead 15 exhibited potent inhibitory activity against PDE8A (IC50 = 11 nmol/L), high selectivity over other PDEs, and remarkable drug-like properties (worthy to mention is that its bioavailability was up to 100%). Oral administration of 15 significantly improved the cAMP level of the right brain and exhibited dose-dependent effects on cognitive improvement in a VaD mouse model. Notably, the X-ray crystal structure of the PDE8A-15 complex showed that the potent affinity and high selectivity of 15 might come from the distinctive interactions with H-pocket including T-shaped π-π interactions with Phe785 as well as a unique H-bond network, which have never been observed in other PDE-inhibitor complex before, providing new strategies for the further rational design of novel selective inhibitors against PDE8.

15.
Chinese Journal of School Health ; (12): 425-428, 2022.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-923144

RESUMO

Objective@#Functional near infrared spectroscopy (fNIRS) was used to assess brain oxygenated hemoglobin (Oxy Hb) activation in college students with different sleep quality under the verbal fluency task (VFT), so as to better provide a theoretical basis for the neural mechanism for sleep quality improvement of college students.@*Methods@#A simple random sampling method was used to investigate 96 college students from one university during 2020 and 2021. According to the results of the Pittsburgh Sleep Quality Index(PSQI), participants were divided into 3 groups: good sleep quality group( n =45), moderate group( n =33), and poor group( n =18). The 53 channel near infrared spectroscopy to collect cerebral blood oxygen signals under the VFT task. Association between oxygenated hemoglobin with sleep quality was analyzed.@*Results@#About 18.75% of college students reported sleep quality problems, including long sleep latency (0.97±0.97) and poor subjective sleep quality (0.96±0.72). There was a significant negative correlation between PSQI score and average oxygenated hemoglobin (Avg HbO) index of dorsolateral prefrontal lobe ( r =-0.23, P =0.03). The Avg HbO index differed significantly between good and poor sleep quality groups on dorsolateral prefrontal lobe( P =0.05).@*Conclusion@#This study verified that there is a positive correlation between sleep quality and cognitive ability among college students. The fNIRS technique could accurately collect blood oxygen signals from dorsolateral prefrontal lobe during cognitive tasks, which proves to be an effective tool for identifying sleep quality of college students.

16.
Acta Pharmaceutica Sinica B ; (6): 1351-1362, 2022.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-929342

RESUMO

Scaffold hopping refers to computer-aided screening for active compounds with different structures against the same receptor to enrich privileged scaffolds, which is a topic of high interest in organic and medicinal chemistry. However, most approaches cannot efficiently predict the potency level of candidates after scaffold hopping. Herein, we identified potent PDE5 inhibitors with a novel scaffold via a free energy perturbation (FEP)-guided scaffold-hopping strategy, and FEP shows great advantages to precisely predict the theoretical binding potencies ΔG FEP between ligands and their target, which were more consistent with the experimental binding potencies ΔG EXP (the mean absolute deviations | Δ G FEP - Δ G EXP |  < 2 kcal/mol) than those ΔG MM-PBSA or ΔG MM-GBSA predicted by the MM-PBSA or MM-GBSA method. Lead L12 had an IC50 of 8.7 nmol/L and exhibited a different binding pattern in its crystal structure with PDE5 from the famous starting drug tadalafil. Our work provides the first report via the FEP-guided scaffold hopping strategy for potent inhibitor discovery with a novel scaffold, implying that it will have a variety of future applications in rational molecular design and drug discovery.

17.
Acta Pharmaceutica Sinica B ; (6): 853-866, 2022.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-929330

RESUMO

N 6-methyladenosine (m6A) modification is critical for mRNA splicing, nuclear export, stability and translation. Fat mass and obesity-associated protein (FTO), the first identified m6A demethylase, is critical for cancer progression. Herein, we developed small-molecule inhibitors of FTO by virtual screening, structural optimization, and bioassay. As a result, two FTO inhibitors namely 18077 and 18097 were identified, which can selectively inhibit demethylase activity of FTO. Specifically, 18097 bound to the active site of FTO and then inhibited cell cycle process and migration of cancer cells. In addition, 18097 reprogrammed the epi-transcriptome of breast cancer cells, particularly for genes related to P53 pathway. 18097 increased the abundance of m6A modification of suppressor of cytokine signaling 1 (SOCS1) mRNA, which recruited IGF2BP1 to increase mRNA stability of SOCS1 and subsequently activated the P53 signaling pathway. Further, 18097 suppressed cellular lipogenesis via downregulation of peroxisome proliferator-activated receptor gamma (PPARγ), CCAAT/enhancer-binding protein alpha (C/EBPα), and C/EBPβ. Animal studies confirmed that 18097 can significantly suppress in vivo growth and lung colonization of breast cancer cells. Collectively, we identified that FTO can work as a potential drug target and the small-molecule inhibitor 18097 can serve as a potential agent against breast cancer.

18.
Front Bioeng Biotechnol ; 9: 811287, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34938726

RESUMO

The value-added utilization of tobacco stalk lignin is the key to the development of tobacco stalk resources. However, the serious heterogeneity is the bottleneck for making full use of tobacco stalk lignin. Based on this, lignin was separated from tobacco stalk through hydrothermal assisted dilute alkali pretreatment. Subsequently, the tobacco stalk alkaline lignin was fractionated into five uniform lignin components by sequential solvent fractionation. Advanced spectral technologies (FT-IR, NMR, and GPC) were used to reveal the effects of hydrothermal assisted dilute alkali pretreatment and solvent fractionation on the structural features of tobacco stalk lignin. The lignin fractions extracted with n-butanol and ethanol had low molecular weight and high phenolic hydroxyl content, thus exhibiting superior chemical reactivity and antioxidant capacity. By contrast, the lignin fraction extracted with dioxane had high molecular weight and low reactivity, nevertheless, the high residual carbon rate made it suitable as a precursor for preparing carbon materials. In general, hydrothermal assisted dilute alkali pretreatment was proved to be an efficient method to separate lignin from tobacco stalk, and the application of sequential solvent fractionation to prepare lignin fractions with homogeneous structural features has specific application prospect.

19.
ACS Appl Mater Interfaces ; 13(48): 57489-57496, 2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34839656

RESUMO

Lithium (Li) metal batteries are promising future rechargeable batteries with high-energy density as the Li metal anode (LMA) possesses a high specific capacity and the lowest potential. However, the commercial application of the LMA has been hindered by a low Coulombic efficiency and dendrite growth, which are related to the unstable interphase with poor Li+ ion transport. Herein, we report novel polymer zwitterion-based artificial interphase layers (AILs) with improved Li+ ion transport and high stability for long-life LMAs. Benefitting from the unique zwitterion effect within the polymer zwitterion-based AILs, a high Li+ ion transference number (0.81) and a good ionic conductivity (0.75 × 10-4 S cm-1) can be realized simultaneously at the interface. By regulating the weight ratio of the sulfonate group and the phosphate group in polymer zwitterion-based AILs, the modified LMA enables long-term Li plating/stripping for 1400 h at 1 mA cm-2 and stable cycling in a full cell. This interfacial engineering concept could shed light on the development of safe LMAs.

20.
Adv Mater ; 33(24): e2100608, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33960042

RESUMO

The growth of lithium (Li) dendrites and the huge volume change are the critical issues for the practical applications of Li-metal anodes. In this work, a spatial control strategy is proposed to address the above challenges using lotus-root-like Ni-Co hollow prisms@carbon fibers (NCH@CFs) as the host. The homogeneously distributed bimetallic Ni-Co particles on the N-doped carbon fibers serve as nucleation sites to effectively reduce the overpotential for Li nucleation. Furthermore, the 3D conductive network can alter the electric field. More importantly, the hierarchical lotus-root-like hollow fibers provide sufficient void space to withstand the volume expansion during Li deposition. These structural features guide the uniform Li nucleation and non-dendritic growth. As a result, the NCH@CFs host enables a very stable Li metal anode with a low voltage hysteresis during repeated Li plating/stripping for 1200 h at a current density of 1 mA cm-2 .

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