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1.
Small ; : e2309346, 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-38072793

RESUMO

Al-Si dealloying method is widely used to prepare Si anode for alleviating the issues caused by a drastic volume change of Si-based anode. However, this method suffers from the problems of low Si powder yield (<20 wt.% Si) and complicated cooling equipment due to the hindrance of large-size primary Si particles. Here, a new modification strategy to convert primary Si to 2D SiOx nanosheets by introducing a Ca modifier into Al-Si alloy melt is presented. The thermodynamics calculation shows that the primary Si is preferentially converted to CaAl2 Si2 intermetallic compound in Al-Si-Ca alloy system. After the dealloying process, the CaAl2 Si2 is further converted to 2D SiOx nanosheets, and eutectic Si is converted to 3D Si, thus obtaining the 2D SiOx -3D Si hybrid Si-based materials (HSiBM). Benefiting from the modification effect, the HSiBM anode shows a significantly improved electrochemical performance, which delivers a capacity retention of over 90% after 100 cycles and keeps 98.94% capacity after the rate test. This work exhibits an innovative approach to produce stable Si-based anode through Al-Si dealloying method with a high Si yield and without complicated rapid cooling techniques, which has a certain significance for the scalable production of Si-based anodes.

2.
Nano Lett ; 22(8): 3298-3306, 2022 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-35385667

RESUMO

Aqueous Zn batteries are emerging as promising energy storage devices. However, severe dendrite growth and side reactions of Zn anodes restrict their further development. Herein, we develop a nucleophilic interfacial layer (NIL) on Zn to achieve a highly stable Zn anode for rechargeable Zn batteries. The NIL in a composition of zinc acetate acetamide is homogeneous, compact, and Zn2+-conductive, rendering dendrite-free Zn deposition, which is observed by in situ optical microscopy. Benefiting from the advantages of NIL, the Zn||Zn symmetric cells show a low overpotential of 0.12 V at a high current density of 40 mA/cm2, enhanced Coulombic efficiency up to 99.9%, and extended lifespan over 2600 cycles. The Zn||Ti asymmetric cells exhibit a high areal capacity of 5 mAh/cm2. Moreover, the NIL functionalized Zn anode enables stable cycling of both anode-free Zn||Cl2 cells and zinc-ion capacitors, providing opportunities for the development of high-performance energy storage devices.


Assuntos
Fontes de Energia Elétrica , Zinco , Eletrodos , Microscopia
3.
Nano Lett ; 22(19): 7860-7866, 2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36166748

RESUMO

Rechargeable hydrogen gas batteries (RHGBs) have been attracting much attention as promising all-climate large-scale energy storage devices, which calls for low-cost and high-activity hydrogen evolution/oxidation reaction (HER/HOR) bifunctional electrocatalysts to replace the costly platinum-based catalysts. Based on density functional theory (DFT) computations, herein we report an effective descriptor-driven design principle to govern the HER/HOR electrocatalytic activity of double-atom catalysts (DACs) for RHGBs. We systematically investigate the d-band center variation of DACs and their correlations with HER/HOR free energies. We construct activity maps with the d-band center of DACs as a descriptor, which demonstrate that high HER/HOR electrocatalytic activity can be achieved with an appropriate d-band center of DACs. This work not only broadens the applicability of d-band center theory to the prediction of bifunctional HER/HOR electrocatalysts but also paves the way to fast screening and design of efficient and low-cost DACs to promote practical applications of RHGBs.

4.
Angew Chem Int Ed Engl ; 62(3): e202214966, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36334063

RESUMO

Aqueous zinc-ion batteries (AZBs) show promises for large-scale energy storage. However, the zinc utilization rate (ZUR) is generally low due to side reactions in the aqueous electrolyte caused by the active water molecules. Here, we design a novel solvation structure in the electrolyte by introduction of sulfolane (SL). Theoretical calculations, molecular dynamics simulations and experimental tests show that SL remodels the primary solvation shell of Zn2+ , which significantly reduces the side reactions of Zn anode and achieves high ZUR under large capacities. Specifically, the symmetric and asymmetric cells could achieve a maximum of ∼96 % ZUR at an areal capacity of 24 mAh cm-2 . In a ZUR of ∼67 %, the developed Zn-V2 O5 full cell can be stably cycled for 500 cycles with an energy density of 180 Wh kg-1 and Zn-AC capacitor is stable for 5000 cycles. This electrolyte structural engineering strategy provides new insight into achieving high ZUR of Zn anodes for high performance AZBs.

5.
Nano Lett ; 21(20): 8863-8871, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34633819

RESUMO

An aqueous electrolytic MnO2-Zn battery with eye-catching Mn2+/MnO2 cathode chemistry has been attracting immense interest for next-generation energy storage devices due to its irreplaceable advantages. However, the limited MnO2 conductivity restricts its long service life at high areal capacities. Here, we report a high-performance electrolytic MnO2-Zn battery via a bromine redox mediator, to enhance its electrochemical performance. The MnO2/Br2-Zn battery displays a high discharge voltage of 1.98 V with a capacity of ∼5.8 mAh cm-2. It also shows an excellent rate performance of 20 C with a long-term stability of over 600 cycles. Furthermore, the scaled-up MnO2/Br2-Zn battery with a capacity of ∼950 mAh exhibits a stable 100 cycles with a practical cell energy density of ∼32.4 Wh kg-1 and an attractively low energy cost of below 15 US$ kWh-1. The design approach can be generalized to other electrodes and battery systems, thus opening up new possibilities for large-scale energy storage.

6.
J Am Chem Soc ; 143(48): 20302-20308, 2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34806375

RESUMO

Aqueous proton batteries are regarded as one of the most promising energy technologies for next-generation grid storage due to the distinctive merits of H+ charge carriers with small ionic radius and light weight. Various materials have been explored for aqueous proton batteries; however, their full batteries show undesirable electrochemical performance with limited rate capability and cycling stability. Here we introduce a novel aqueous proton full battery that shows remarkable rate capability, cycling stability, and ultralow temperature performance, which is driven by a hydrogen gas anode and a Prussian blue analogue cathode in a concentrated phosphoric acid electrolyte. Its operation involves hydrogen evolution/oxidation redox reactions on the anode and H+ insertion/extraction reactions on the cathode, in parallel with the ideal transfer of only H+ between these two electrodes. The fabricated aqueous hydrogen gas-proton battery exhibits an unprecedented charge/discharge capability of up to 960 C with a superior power density of 36.5 kW kg-1, along with an ultralong cycle life of over 0.35 million cycles. Furthermore, this hydrogen gas-proton battery is able to work well at an ultralow temperature of -80 °C with 54% of its room-temperature capacity and under -60 °C with a stable cycle life of 1150 cycles. This work provides new opportunities to construct aqueous proton batteries with high performance in extreme conditions for large-scale energy storage.

7.
Heliyon ; 10(8): e29613, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38681626

RESUMO

Background: Previous studies have found electroacupuncture could improve the clinical symptoms of first-episode major depressive disorder (MDD), but the exact neural mechanism of action needs to be further elucidated. Methods: Twenty-eight first-episode MDD patients were randomly divided into 14 electro-acupuncture stimulation (EAS) groups and 14 sham-acupuncture stimulation (SAS) groups, and clinical symptoms were assessed and functional magnetic resonance imaging (fMRI) scans were done in both groups. Amplitude of low-frequency fluctuations (ALFF) was used to observe the changes between the pre-treatment and post-treatment in the two groups, and the altered brain areas were selected as region of interest (ROI) to observe the FC changes. Meanwhile, the correlation between the altered clinical symptoms and the altered ALFF and FC of brain regions in the two groups was analyzed. Results: The EAS significantly decreased the HAMD-24 and HAMA-14 scores of MDD than SAS group. The imaging results revealed that both groups were able to increase the ALFF of the left middle temporal gyrus and the left cerebellar posterior lobe. When using the left middle temporal gyrus and the left posterior cerebellar lobe as ROIs, EAS group increased the FC between the left middle temporal gyrus with the left superior frontal gyrus, the left middle frontal gyrus, and the left hippocampus, and decreased the FC between the left posterior cerebellar lobe and the left calcarine gyrus, while SAS group only increased the FC between the left middle temporal gyrus with the left superior frontal gyrus. The alternations in clinical symptoms after EAS treatment were positively correlated with the altered ALFF values in the left middle temporal gyrus and the altered FC values in the left middle temporal gyrus and the left middle frontal gyrus. Conclusion: EA demonstrates modulation of functional activity in the default mode network (DMN), sensorimotor network (SMN), cognitive control network (CCN), limbic system, and visual network (VN) for the treatment of the first-episode MDD. Our findings contribute to the neuroimaging evidence for the efficacy of EAS.

8.
Asian J Psychiatr ; 98: 104079, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38838458

RESUMO

BACKGROUND: In order to improve taVNS efficacy, the usage of fMRI to explore the predictive neuroimaging markers would be beneficial for screening the appropriate MDD population before treatment. METHODS: A total of 86 MDD patients were recruited in this study, and all subjects were conducted with the clinical scales and resting-state functional magnetic resonance imaging (fMRI) scan before and after 8 weeks' taVNS treatment. A two-stage feature selection strategy combining Machine Learning and Statistical was used to screen out the critical brain functional connections (FC) that were significantly associated with efficacy prediction, then the efficacy prediction model was constructed for taVNS treating MDD. Finally, the model was validated by separated the responding and non-responding patients. RESULTS: This study showed that taVNS produced promising clinical efficacy in the treatment of mild and moderate MDD. Eleven FCs were selected out and were found to be associated with the cortico-striatal-pallidum-thalamic loop, the hippocampus and cerebellum and the HAMD-17 scores. The prediction model was created based on these FCs for the efficacy prediction of taVNS treatment. The R-square of the conducted regression model for predicting HAMD-17 reduction rate is 0.44, and the AUC for classifying the responding and non-responding patients is 0.856. CONCLUSION: The study demonstrates the validity and feasibility of combining neuroimaging and machine learning techniques to predict the efficacy of taVNS on MDD, and provides an effective solution for personalized and precise treatment for MDD.

9.
Front Psychiatry ; 14: 1203444, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38034928

RESUMO

Introduction: Several small sample-sized clinical trials have demonstrated a beneficial effect of statin on depressive mood among major depressive disorder (MDD) patients. However, observational studies have showed the increased risk of anxiety/depression with statin treatment. Therefore, we aimed to evaluate the effects of statin on depressive mood and inflammation status among MDD patients. Methods: We performed an updated meta-analysis RCTs identified in systematic searches of PubMed, Cochrane library, Embase, ClinicalTrials.gov, CNKI, Wan fang, VIP, and SinoMed database (up to August 2023). The primary endpoint was the Hamilton depression rating scale (HDRS). The secondary endpoints were rate of response to treatment, remission rate, levels of C-reactive protein (CRP), cognition and blood lipid. We evaluated the certainty of the evidence using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. Results: The search identified seven RCTs involving 448 patients with a median follow-up of 10.4 weeks (range, 6-12 weeks). Compared with selective serotonin reuptake inhibitors (SSRIs) alone, treatment with statin plus SSRIs was associated with a significantly decreased HDRS [mean difference (MD) = -2.79; 95% confidence interval (CI): -3.83 to -1.76] and C-reactive protein (MD = -0.42 mg/L; 95% CI: -0.53 to -0.12 mg/L), and decreased levels of lipid profiles (P < 0.05). Moreover, statin plus SSRIs was associated with a comparable rate of treatment response [relative risk (RR) = 1.26; 95% CI: 0.98 to 1.62], remission rate (RR = 1.33; 95% CI: 0.89 to 1.99). Meta-regression indicated that the follow-up period was a source of heterogeneity regarding the HDRS (r = 0.302, P = 0.041). The quality of evidence was rated as moderate for HDRS and response rate according to the GRADE. Conclusion: Statin could safely and effectively improve the symptoms of depression and inflammation status among MDD patients. Systematic review registration: https://inplasy.com/inplasy-2022-3-0016/, identifier INPLASY2022230016.

10.
J Affect Disord ; 325: 513-521, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36642310

RESUMO

BACKGROUND: Previous studies have found that transcutaneous auricular vagus nerve stimulation (taVNS) is clinically effective in the treatment of major depressive disorder (MDD), and its efficacy mechanism is related to modulation of the default mode network (DMN) and cognitive control network (CCN). However, the mechanism of the immediate effect of taVNS for MDD remains to be elucidated. METHODS: A total of 58 patients with MDD and 54 healthy controls(HCs) were included in this study. The MDD group was treated with taVNS for 30 min (20 Hz, 4-6 mA) immediately, and we observed amplitude of low-frequency fluctuations (ALFF) abnormalities in the MDD group and changes in ALFF and functional connectivity (FC) before and after immediate treatment. The ALFF brain regions altered by taVNS induction were used as regions of interest to analyze whole-brain FC changes in the MDD group. RESULTS: After taVNS treatment, ALFF in the right precuneus was decreased in the MDD group. The FC of the right precuneus with the left middle frontal gyrus, the left posterior cingulate gyrus and the left angular gyrus were decreased in the MDD group. Correlation analysis showed that the FC values between the right precuneus and the left posterior cingulate gyrus in the pre-treatment MDD group was negatively correlated with the 17-item Hamilton depression rating scale scores. CONCLUSION: TaVNS has an immediate modulatory effect on DMN and CCN. It would be proposed that these functional networks may be effective targets for the long-term treatment of MDD patients with taVNS.


Assuntos
Transtorno Depressivo Maior , Estimulação Elétrica Nervosa Transcutânea , Estimulação do Nervo Vago , Humanos , Transtorno Depressivo Maior/diagnóstico por imagem , Transtorno Depressivo Maior/terapia , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Lobo Parietal , Nervo Vago
11.
Neurosci Lett ; 814: 137414, 2023 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-37544579

RESUMO

Transcutaneous electrical cranial-auricular acupoint stimulation (TECAS) is an innovative, non-invasive therapy for major depressive disorder (MDD). However, its effectiveness and underlying neural mechanisms remain not fully understood. This study aimed to investigate the treatment response and neurological effects of TECAS compared to escitalopram, a commonly used depression medication, using resting-state functional magnetic resonance imaging (rs-fMRI). Fifty-one patients with mild-to-moderate MDD (34 in the TECAS group and 17 in the Escitalopram group) and 51 healthy controls (HCs) participated in the study. We employed the low-frequency fluctuations (ALFF) and regional homogeneity (ReHo) methods to explore brain abnormalities in MDD patients and HCs. Additionally, seed-based functional connectivity (FC) analysis was conducted to examine altered brain networks before and after treatment.Compared to the HCs group, the MDD group exhibited lower ReHo and ALFF values in the right medial superior frontal gyrus (mSFG_R), indicating altered neural activity in this region. Furthermore, mSFG-based FC analysis revealed abnormal FC values in the right inferior occipital gyrus (IOG_R) and middle temporal gyrus (MTG) between after and before treatment in MDD patients. Interestingly, TECAS treatment was found to normalize these abnormal FC brain regions, suggesting its potential role in restoring neural connectivity in MDD patients. Notably, both TECAS and escitalopram demonstrated equivalent antidepressant efficacy, with both treatments showing modulatory effects on connectivity within the default mode network (DMN). The observed normalization of abnormal FC regions, including mSFG_R, IOG_R, and MTG, all belong to the DMN. In conclusion, this study sheds light on the neurological effects and treatment response of TECAS in MDD, highlighting its potential as a non-invasive therapeutic option for depressed patients.


Assuntos
Transtorno Depressivo Maior , Humanos , Transtorno Depressivo Maior/diagnóstico por imagem , Transtorno Depressivo Maior/tratamento farmacológico , Escitalopram , Imageamento por Ressonância Magnética/métodos , Pontos de Acupuntura , Encéfalo
12.
Psychiatry Res Neuroimaging ; 328: 111567, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36462466

RESUMO

Major depressive disorder is associated with a reward deficit manifested by abnormal striatal function. However, differences between treatment-resistant depression (TRD) and non TRD (nTRD) in striatal whole-brain functional connectivity (FC) have not been elucidated. Thirty-eight patients with TRD, 42 patients with nTRD, and 39 healthy controls (HCs) were recruited for this study. A seed-based FC approach was used to analyze abnormalities in six predefined striatal subregion circuits in the three groups of subjects, and further explore the correlation between abnormal FC and clinical symptoms. Results revealed that compared with the nTRD group, the TRD group showed increased FC of the inferior ventral striatum with the bilateral orbital area of the middle frontal gyrus, right cerebellum posterior lobe, left parahippocampal gyrus, left middle occipital gyrus and left lingual gyrus. Compared with the HC group, the TRD group showed a wider range of altered striatal function than the nTRD group. In the TRD group, the HAMD-17 scores were positively correlated with the FC between the right VRP and the left caudate. This study provides new insights into understanding the specificity of TRD striatal circuits.


Assuntos
Transtorno Depressivo Maior , Estriado Ventral , Humanos , Transtorno Depressivo Maior/diagnóstico por imagem , Depressão , Imageamento por Ressonância Magnética , Encéfalo , Estriado Ventral/diagnóstico por imagem
13.
JACS Au ; 3(2): 488-497, 2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36873693

RESUMO

In conventional water electrolysis (CWE), the H2 and O2 evolution reactions (HER/OER) are tightly coupled, making the generated H2 and O2 difficult to separate, thus resulting in complex separation technology and potential safety issues. Previous efforts on the design of decoupled water electrolysis mainly concentrated on multi-electrode or multi-cell configurations; however, these strategies have the limitation of involving complicated operations. Here, we propose and demonstrate a pH-universal, two-electrode capacitive decoupled water electrolyzer (referred to as all-pH-CDWE) in a single-cell configuration by utilizing a low-cost capacitive electrode and a bifunctional HER/OER electrode to separate H2 and O2 generation for decoupling water electrolysis. In the all-pH-CDWE, high-purity H2 and O2 generation alternately occur at the electrocatalytic gas electrode only by reversing the current polarity. The designed all-pH-CDWE can maintain a continuous round-trip water electrolysis for over 800 consecutive cycles with an electrolyte utilization ratio of nearly 100%. As compared to CWE, the all-pH-CDWE achieves energy efficiencies of 94% in acidic electrolytes and 97% in alkaline electrolytes at a current density of 5 mA cm-2. Further, the designed all-pH-CDWE can be scaled up to a capacity of 720 C in a high current of 1 A for each cycle with a stable HER average voltage of 0.99 V. This work provides a new strategy toward the mass production of H2 in a facilely rechargeable process with high efficiency, good robustness, and large-scale applications.

14.
Adv Mater ; 35(42): e2305368, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37459236

RESUMO

The development of safe and high-energy metal anodes represents a crucial research direction. Here, the achievement of highly reversible, dendrite-free transition metal anodes with ultrahigh capacities by regulating aqueous electrolytes is reported. Using nickel (Ni) as a model, theoretical and experimental evidence demonstrating the beneficial role of chloride ions in inhibiting and disrupting the nickel hydroxide passivation layer on the Ni electrode is provided. As a result, Ni anodes with an ultrahigh areal capacity of 1000 mAh cm-2 (volumetric capacity of ≈6000 mAh cm-3 ), and a Coulombic efficiency of 99.4% on a carbon substrate, surpassing the state-of-the-art metal electrodes by approximately two orders of magnitude, are realized. Furthermore, as a proof-of-concept, a series of full cells based on the Ni anode is developed. The designed Ni-MnO2 full battery exhibits a long lifespan of 2000 cycles, while the Ni-PbO2 full battery achieves a high areal capacity of 200 mAh cm-2 . The findings of this study are important for enlightening a new arena toward the advancement of dendrite-free Ni-metal anodes with ultrahigh capacities and long cycle life for various energy-storage devices.

15.
Artigo em Inglês | MEDLINE | ID: mdl-36031163

RESUMO

BACKGROUND: Previous neuroimaging has paid little attention to the differences in brain network integration between patients with treatment-resistant depression(TRD) and non-TRD (nTRD), and the relationship between their impaired brain network integration and clinical symptoms has not been elucidated. METHOD: Eighty one major depressive disorder (MDD) patients (40 in TRD, 41 in nTRD) and 40 healthy controls (HCs) were enrolled for the functional magnetic resonance imaging (fMRI) scans. A seed-based functional connectivity (FC) method was used to investigate the brain network abnormalities of default mode network (DMN), affective network (AN), salience network (SN) and cognitive control network (CCN) for the MDD. Finally, the correlation was analyzed between the abnormal FCs and 17-item Hamilton Rating Scale for Depression scale (HAMD-17) scores. RESULTS: Compared with the HC group, the FCs in DMN, AN, SN, CCN were altered in both the TRD and nTRD groups. Compared with the nTRD group, FC alterations in the AN and CCN were more abnormal in the TRD group, and the FC alterations were generally decreased at the SN in the TRD group. In addition, the FC values of right dorsolateral prefrontal cortices and left caudate nucleus in the TRD group and the FC values of right subgenual anterior cingulate cortex and left middle temporal gyrus in the nTRD group were positively correlated with HAMD-17 scale scores. CONCLUSIONS: Abnormal FCs are present in four brain networks (DMN, AN, SN, CCN) in both the TRD and nTRD groups. Except of DMN, FCs in AN, SN and CCN maybe underlay the neurobiological mechanism in differentiating TRD from nTRD.


Assuntos
Mapeamento Encefálico , Transtorno Depressivo Maior , Humanos , Transtorno Depressivo Maior/diagnóstico por imagem , Depressão , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética
16.
Adv Mater ; 35(32): e2300502, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37249173

RESUMO

The high reliability and proven ultra-longevity make aqueous hydrogen gas (H2 ) batteries ideal for large-scale energy storage. However, the low alkaline hydrogen evolution and oxidation reaction (HER/HOR) activities of expensive platinum catalysts severely hamper their widespread applications in H2 batteries. Here, cost-effective, highly active electrocatalysts, with a model of ruthenium-nickel alloy nanoparticles in ≈3 nm anchored on carbon black (RuNi/C) as an example, are developed by an ultrafast electrical pulse approach for nickel-hydrogen gas (NiH2 ) batteries. Having a competitive low cost of about one fifth of Pt/C benckmark, this ultrafine RuNi/C catalyst displays an ultrahigh HOR mass activity of 2.34 A mg-1 at 50 mV (vs RHE) and an ultralow HER overpotential of 19.5 mV at a current density of 10 mA cm-2 . As a result, the advanced NiH2 battery can efficiently operate under all-climate conditions (from -25 to +50 °C) with excellent durability. Notably, the NiH2 cell stack achieves an energy density up to 183 Wh kg-1 and an estimated cost of ≈49 $ kWh-1 under an ultrahigh cathode Ni(OH)2 loading of 280 mg cm-2 and a low anode Ru loading of ≈62.5 µg cm-2 . The advanced beyond-industrial-level hydrogen gas batteries provide great opportunities for practical grid-scale energy storage applications.

17.
Small Methods ; : e2201553, 2023 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-37086122

RESUMO

Aqueous zinc-chlorine battery with high discharge voltage and attractive theoretical energy density is expected to become an important technology for large-scale energy storage. However, the practical application of Zn-Cl2 batteries has been restricted due to the Cl2 cathode with sluggish kinetics and low Coulombic efficiency (CE). Here, an aqueous Zn-Cl2 battery using an inexpensive and effective MnO2 redox adsorbent (referred to Zn-Cl2 @MnO2 battery) to modulate the electrochemical performance of the Cl2 cathode is developed. Density functional theory calculations reveal that the existence of the intermediate state Clads free radical catalyzed by MnO2 on the Cl2 cathode contributes to the charge storage capacity, which is the key to modulate the electrode and improve the electrochemical performance. Further analysis of the Cl2 cathode kinetics discloses the adsorption and catalytic roles of the MnO2 redox adsorbent. The Zn-Cl2 @MnO2 battery displays an enhanced discharge voltage of 2.0 V at a current density of 2.5 mA cm-2 , and stable 1000 cycles with an average CE of 91.6%, much superior to the conventional Zn-Cl2 battery with an average CE of only 66.8%. The regulation strategy to the Cl2 cathode provides opportunities for the future development of aqueous Zn-Cl2 batteries.

18.
Zhongguo Zhen Jiu ; 43(4): 367-73, 2023 Apr 12.
Artigo em Chinês | MEDLINE | ID: mdl-37068810

RESUMO

OBJECTIVE: To explore the brain effect mechanism and the correlation between brain functional imaging and cognitive function in treatment of depressive disorder (DD) with transcutaneous auricular vagus nerve stimulation (taVNS) based on the resting-state functional magenetic reasonance imaging (rs-fMRI). METHODS: Thirty-two DD patients were included in a depression group and 32 subjects of healthy condition were enrolled in a normal group. In the depression group, the taVNS was applied to bilateral Xin (CO15) and Shen (CO10), at disperse-dense wave, 4 Hz/20 Hz in frequency and current intensity ≤20 mA depending on patient's tolerance, 30 min each time, twice daily. The duration of treatment consisted of 8 weeks. The patients of two groups were undertaken rs-fMRI scanning. The scores of Hamilton depression scale (HAMD), Hamilton anxiety scale (HAMA) and Wisconsin card sorting test (WCST) were observed in the normal group at baseline and the depression group before and after treatment separately. The differential brain regions were observed before and after treatment in the two groups and the value of degree centrality (DC) of fMRI was obtained. Their correlation was analyzed in terms of HAMD, HAMA and WCST scores. RESULTS: The scores of HAMD and HAMA in the depression group were all higher than those in the normal group (P<0.05). After treatment, the scores of HAMD and HAMA were lower than those before treatment in the depression group; the scores of total responses, response errors and perseverative errors of WCST were all lower than those before treatment (P<0.05). The brain regions with significant differences included the left inferior temporal gyrus, the left cerebellar peduncles region 1, the left insula, the right putamen, the bilateral supplementary motor area and the right middle frontal gyrus. After treatment, the value of DC in left supplementary motor area was negatively correlated to HAMD and HAMA scores respectively (r=-0.324, P=0.012; r=-0.310, P=0.015); the value of DC in left cerebellar peduncles region 1 was negatively correlated to the total responses of WCST (r=-0.322, P=0.013), and the left insula was positively correlated to the total responses of WCST (r=0.271, P=0.036). CONCLUSION: The taVNS can modulate the intensity of the functional activities of some brain regions so as to relieve depressive symptoms and improve cognitive function.


Assuntos
Estimulação Elétrica Nervosa Transcutânea , Estimulação do Nervo Vago , Humanos , Depressão/diagnóstico por imagem , Depressão/terapia , Imageamento por Ressonância Magnética/métodos , Estimulação do Nervo Vago/métodos , Encéfalo/diagnóstico por imagem , Estimulação Elétrica Nervosa Transcutânea/métodos , Nervo Vago
19.
Nat Commun ; 14(1): 76, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36604413

RESUMO

The development of Zn-free anodes to inhibit Zn dendrite formation and modulate high-capacity Zn batteries is highly applauded yet very challenging. Here, we design a robust two-dimensional antimony/antimony-zinc alloy heterostructured interface to regulate Zn plating. Benefiting from the stronger adsorption and homogeneous electric field distribution of the Sb/Sb2Zn3-heterostructured interface in Zn plating, the Zn anode enables an ultrahigh areal capacity of 200 mAh cm-2 with an overpotential of 112 mV and a Coulombic efficiency of 98.5%. An anode-free Zn-Br2 battery using the Sb/Sb2Zn3-heterostructured interface@Cu anode shows an attractive energy density of 274 Wh kg-1 with a practical pouch cell energy density of 62 Wh kg-1. The scaled-up Zn-Br2 battery in a capacity of 500 mAh exhibits over 400 stable cycles. Further, the Zn-Br2 battery module in an energy of 9 Wh (6 V, 1.5 Ah) is integrated with a photovoltaic panel to demonstrate the practical renewable energy storage capabilities. Our superior anode-free Zn batteries enabled by the heterostructured interface enlighten an arena towards large-scale energy storage applications.

20.
Adv Mater ; 34(33): e2203249, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35766725

RESUMO

Aqueous electrolytic MnO2 -Zn batteries are considered as one of the most promising energy-storage devices for their cost effectiveness, high output voltage, and safety, but their electrochemical performance is limited by the sluggish kinetics of cathodic MnO2 /Mn2+ and anodic Zn/Zn2+ reactions. To overcome this critical challenge, herein, a cationic accelerator (CA) strategy is proposed based on the prediction of first-principles calculations. Poly(vinylpyrrolidone) is utilized as a model to testify the rational design of the CA strategy. It manifests that the CA effectively facilitates rapid cations migration in electrolyte and adequate charge transfer at electrode-electrolyte interface, benefiting the deposition/dissolution processes of both Mn2+ and Zn2+ cations to simultaneously improve kinetics of cathodic MnO2 /Mn2+ and anodic Zn/Zn2+ reactions. The resulting MnO2 -Zn battery regulated by CA exhibits large reversible capacities of 455 mAh g-1 and 3.64 mAh cm-2 at 20 C, as well as a long lifespan of 2000 cycles with energy density retention of 90%, achieving one of the best overall performances in the electrolytic MnO2 -Zn batteries. This comprehensive work integrating theoretical prediction with experimental studies provides opportunities to the development of high-performance energy-storage devices.

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