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1.
J Fungi (Basel) ; 10(4)2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38667936

RESUMEN

The biocontrol agent Pythium oligandrum, which is a member of the phylum Oomycota, can control diseases caused by a taxonomically wide range of plant pathogens, including fungi, bacteria, and oomycetes. However, whether P. oligandrum could control diseases caused by plant root-knot nematodes (RKNs) was unknown. We investigated a recently isolated P. oligandrum strain GAQ1, and the P. oligandrum strain CBS530.74, for the control of an RKN Meloidogyne incognita infection of tomato (Solanum lycopersicum L.). Initially, P. oligandrum culture filtrates were found to be lethal to M. incognita second-stage juveniles (J2s) with up to 84% mortality 24 h after treatment compared to 14% in the control group. Consistent with the lethality to M. incognita J2s, tomato roots treated with P. oligandrum culture filtrates reduced their attraction of nematodes, and the number of nematodes penetrating the roots was reduced by up to 78%. In a greenhouse pot trial, the P. oligandrum GAQ1 inoculation of tomato plants significantly reduced the gall number by 58% in plants infected with M. incognita. Notably, the P. oligandrum GAQ1 mycelial treatment significantly increased tomato plant height (by 36%), weight (by 27%), and root weight (by 48%). A transcriptome analysis of tomato seedling roots inoculated with the P. oligandrum GAQ1 strain identified ~2500 differentially expressed genes. The enriched GO terms and annotations in the up-regulated genes suggested a modulation of the plant hormone-signaling and defense-related pathways in response to P. oligandrum. In conclusion, our results support that P. oligandrum GAQ1 can serve as a potential biocontrol agent for M. incognita control in tomato. Multiple mechanisms appear to contribute to the biocontrol effect, including the direct inhibition of M. incognita, the potential priming of tomato plant defenses, and plant growth promotion.

2.
J Clin Anesth ; 92: 111301, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-37865021

RESUMEN

STUDY OBJECTIVE: The incidence of pruritus from neuraxial opioids is about 60%. Pruritus causes discomfort and decreases the quality of recovery. This randomized double-blinded clinical trial was aimed to evaluate the prophylactic effects of a single dose IV nalmefene on the incidence and severity of epidural opioid-induced pruritus within 24 h after surgeries. DESIGN: A two-center, randomized, double blinded, controlled clinical trial. SETTING: The study was conducted from March 2022 to February 2023 at two tertiary care hospitals in China. PATIENTS: Patients aged between 18 and 80 years-old who underwent elective surgeries and received epidural analgesia intra- and post-operatively were screened for study enrollment. A total of 306 patients were enrolled, 302 patients underwent randomization and 296 patients were included in the final analysis. INTERVENTIONS: The nalmefene group was prophylactically given 0.5 µg/kg nalmefene intravenously while the control group was given the same volume of saline. MEASUREMENTS: The primary endpoint was the incidence of pruritus within 24 h after surgeries. The secondary endpoints included time of the first patient-reported pruritus, severity of pruritus after surgeries, severity of acute pain scores after surgeries and other anesthesia/analgesia related side effects. MAIN RESULTS: Pruritus occurred in 51 of the 147 (34.69%) patients in the control group and 35 of the 149 (23.49%) patients in the nalmefene group (odds ratio, 0.58; 95% CI, 0.35 to 0.96; P = 0.034) within 24 h postoperatively. Nalmefene group demonstrated delayed onset of pruritus, reduced severity of pruritus and decreased vomiting within 24 h after surgery. There were no significant differences in postoperative analgesia and the incidence of other anesthesia/analgesia associated side effects. CONCLUSIONS: A single dose of 0.5 µg/kg nalmefene intravenously significantly reduced the incidence and severity of epidural-opioid induced pruritus within 24 h after surgery without affecting the efficacy of epidural analgesia. TRIAL REGISTRATION: Chinese Clinical Trial Registry (www.chictr.org.cn) and the registration number is ChiCTR2100050463. Registered on August 27th, 2021.


Asunto(s)
Analgesia Epidural , Analgésicos Opioides , Humanos , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Morfina , Dolor Postoperatorio/tratamiento farmacológico , Dolor Postoperatorio/prevención & control , Prurito/inducido químicamente , Prurito/epidemiología , Prurito/prevención & control , Analgesia Epidural/efectos adversos , Método Doble Ciego
3.
J Phys Chem Lett ; 14(49): 10863-10869, 2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-38032733

RESUMEN

Solid electrolyte interphase (SEI) is regarded as a key factor to enable high power outputs of Lithium-ion batteries (LIBs). Herein, we demonstrate a modified electrolyte consisting of a novel electrolyte additive, 1H,1H,2H,2H-perfluorooctyltrimethoxysilane (FTMS) to construct a highly robust and stable SEI on a graphite anode for LIBs to enhance its rate performance. With 2% FTMS, the anode presents an improved capacity retention from 77.6 to 91.2% at 0.5 C after 100 cycles and an improved capacity from 86 to 229 mAh g-1 at 2 C. Experimental characterizations and theoretical calculations reveal that FTMS is preferentially absorbed and reduced on graphite to construct an interface chemistry with uniform fluoride-containing organic lithium salt and silicon-containing polymer, which exhibits high flexibility and conductivity and endows the SEI with high robustness and stability. This work provides an effective way to address the issue of slow lithium insertion/desertion kinetics of graphite anodes.

4.
Phys Chem Chem Phys ; 25(37): 25205-25213, 2023 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-37724059

RESUMEN

To endow microbial fuel cells (MFCs) with low cost, long-term stability and high-power output, a novel cobalt-based cathode electrocatalyst (Nano-Co@NC) is synthesized from a polygonal metal-organic framework ZIF-67. After calcining the resultant ZIF-67, the as-synthesized Nano-Co@NC is characteristic of cobalt nanoparticles (Nano-Co) embedded in nitrogen-doped carbon (NC) that inherits the morphology of ZIF-67 with a large surface area. The Nano-Co particles that are highly dispersed and firmly fixed on NC not only ensure electrocatalytic activity of Nano-Co@NC toward the oxygen reduction reaction on the cathode, but also inhibit the growth of non-electrogenic bacteria on the anode. Consequently, the MFC using Nano-Co@NC as the cathode electrocatalyst demonstrates excellent performance, delivering a comparable initial power density and exhibiting far better durability than that using Pt/C (20 wt%) as the cathode electrocatalyst. The low cost and the excellent performance of Nano-Co@NC make it promising for MFCs to be used in practice.

5.
Phys Chem Chem Phys ; 25(32): 21191-21199, 2023 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-37530031

RESUMEN

A novel composite of iron sulfide, iron carbide and nitrogen carbides (Nano-FeS/Fe3C@NCNTs) as a cathode electrocatalyst for microbial fuel cells (MFCs) is synthesized by a one-pot solid state reaction, which yields a unique configuration of FeS/Fe3C nanoparticles highly dispersed on in situ grown nitrogen-doped carbon nanotubes (NCNTs). The highly dispersed FeS/Fe3C nanoparticles possess large active sites, while the NCNTs provide an electronically conductive network. Consequently, the resultant Nano-FeS/Fe3C@NCNTs exhibit excellent electrocatalytic activity towards the oxygen reduction reaction (ORR), with a half-wave potential close to that of Pt/C (about 0.88 V vs. RHE), and enable MFCs to deliver a power density of 1.28 W m-2 after two weeks' operation, which is higher than that of MFCs with Pt/C as the cathode electrocatalyst (1.02 W m-2). Theoretical calculations and experimental data demonstrate that there is a synergistic effect between Fe3C and FeS in Nano-FeS/Fe3C@NCNTs. Fe3C presents a strong attraction and electron-donating tendency to oxygen molecules, serving as the main active component, while FeS reduces charge transfer resistance by transferring electrons to Fe3C, synergistically improving the kinetics of the ORR and power density of MFCs.

6.
J Colloid Interface Sci ; 642: 292-303, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37004263

RESUMEN

An effective electrolyte additive, 3-(tert-Butyldimethylsilyoxy) phenylboronic acid (TBPB), is proposed to significantly improve the cycle stability of high voltage LiCoO2 (LCO) cathode. Experimental and computational results show that TBPB has a relatively higher oxidation activity than base electrolyte, and preferentially constructs a stable cathode electrolyte interphase (CEI) containing B-/Si- components on LCO surface. Theoretical calculation, XPS and NMR data show that TBPB-derived CEI layer contains B-F species and has the function of eliminating HF. The as-formed CEI effectively inhibits the detrimental side reactions from electrolyte decomposition and LCO surface structure reconstruction. The capacity retention of LCO/Li half-cell increases from 38.92% (base electrolyte) to 83.70% after 150 cycles at 1 C between 3.0 V and 4.5 V by adding 1% TBPB. Moreover, TBPB is also reduced prior to base electrolyte, forming an ionic conducting solid electrolyte interphase (SEI) on graphite surface. Benefiting from the synergistic effect between CEI layer on LCO cathode and SEI layer on graphite anode to effectively decrease the electrolyte decomposition, the capacity retention of commercial LCO/graphite pouch cell with 1% TBPB increases from 10.44% to 76.13% after 400 cycles at 1 C between 3.0 V and 4.5 V. This work demonstrates that TBPB can act as an effective film-forming additive for high energy density LCO cathode at high voltage, and provides novel insights for its commercial application from the aspect of synergistically interfacial stability.

7.
J Phys Chem Lett ; 13(37): 8801-8807, 2022 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-36106726

RESUMEN

Nitriles have been successfully used as electrolyte additives for performance improvement of commercialized lithium-ion batteries based on the LiCoO2 cathode, but the underlying mechanism is unclear. In this work, we present an insight into the contribution of nitriles via experimental and theoretical investigations, taking for example succinonitrile. It is found that succinonitrile can be oxidized together with PF6- preferentially on LiCoO2 compared to the solvents in the electrolyte, making it possible to avoid the formation of hydrogen fluoride from the electrolyte oxidation decomposition, which is detrimental to the LiCoO2 cathode. Additionally, inorganic LiF and -NH group-containing polymers are formed from the preferential oxidation of succinonitrile, constructing a protective interphase on LiCoO2, which suppresses electrolyte oxidation decomposition and prevents LiCoO2 from structural deterioration. Consequently, the LiCoO2 cathode presents excellent stability under cycling and storing at high voltages.

8.
ACS Appl Mater Interfaces ; 14(32): 36656-36667, 2022 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-35925802

RESUMEN

The nickel-rich cathode LiNi0.8Co0.1Mn0.1O2 (NCM811) is deemed as a prospective material for high-voltage lithium-ion batteries (LIBs) owing to its merits of high discharge capacity and low cobalt content. However, the unsatisfactory cyclic stability and thermostability that originate from the unstable electrode/electrolyte interface restrict its commercial application. Herein, a novel electrolyte composed of a polyethylene (PE) supported poly(vinylidene fluoride-co-hexafluoropropylene) (P(VdF-HFP)) based gel polymer electrolyte (GPE) strengthened by a film-forming additive of 3-(trimethylsilyl)phenylboronic acid (TMSPB) is proposed. The porous structure and good oxidative stability of the P(VdF-HFP)/PE membrane help to expand the oxidative potential of GPE to 5.5 V compared with 5.1 V for the liquid electrolyte. The developed GPE also has better thermal stability, contributing to improving the safety performance of LIBs. Furthermore, the TMSPB additive constructs a low-impedance and stable cathode electrolyte interphase (CEI) on the NCM811 cathode surface, compensating for GPE's drawbacks of sluggish kinetics. Consequently, the NCM811 cathode matched with 3% TMSPB-containing GPE exhibits remarkable cyclicity and rate capability, maintaining 94% of its initial capacity after 100 cycles at a high voltage range of 3.0-4.35 V and delivering a capacity of 133.5 mAh g-1 under 15 C high current rate compared with 68% and 75.8 mAh g-1 for the one with an additive-free liquid electrolyte. By virtue of the enhanced stability of the NCM811cathode, the cyclability of graphite||NCM811 full cell also increases from 48 to 81% after 100 cycles. The incorporation of P(VdF-HFP)-based GPE and TMSPB electrolyte additive points out a viable and convenient pathway to unlock the properties of high energy density and satisfactory safety for next-generation LIBs.

9.
J Phys Chem Lett ; : 5151-5159, 2022 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-35658442

RESUMEN

The rate capability of lithium-ion batteries is highly dependent on the interphase chemistry of graphite anodes. Herein, we demonstrate an anode interphase tailoring based on a novel electrolyte additive, lithium dodecyl sulfate (LiDS), which greatly improves the rate capability and cyclic stability of graphite anodes. Upon application of 1% LiDS in a base electrolyte, the discharge capacity at 2 C is improved from 102 to 240 mAh g-1 and its capacity retention is enhanced from 51% to 94% after 200 cycles at 0.5 C. These excellent performances are attributed to the preferential absorption of LiDS and the as-constructed interphase chemistry that is mainly composed of organic long-chain polyether and inorganic lithium sulfite. The long-chain polyether possesses flexibility endowing the interphase with robustness, while its combination with inorganic lithium sulfite accelerates lithium intercalation/deintercalation kinetics via decreasing the resistance for charge transfer.

10.
ChemSusChem ; 15(11): e202200543, 2022 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-35394701

RESUMEN

The nickel-rich cathode LiNi0.8 Co0.1 Mn0.1 O2 (NCM811) possesses the advantages of high reversible specific capacity and low cost, thus regarded as a promising cathode material for lithium-ion batteries (LIBs). However, the capacity of the NCM811 decays rapidly at high voltage due to the extremely unstable electrode/electrolyte interphase. The discharge capability at low temperature is also impaired because of the increasing interfacial impedance. Herein, a low-cost film-forming electrolyte additive with multi-function, phenylboronic acid (PBA), was employed to modify the interphasial properties of the NCM811 cathode. Theoretical calculation and experimental results showed that PBA constructed a highly conductive and steady cathode electrolyte interphase (CEI) film through preferential oxidation decomposition, which greatly improved the interfacial properties of the NCM811 cathode at room (25 °C) and low temperature (-10 °C). Specifically, the capacity retention of NCM811/Li cell was increased from 68 % to 87 % after 200 cycles with PBA additive. Moreover, the NCM811/Li cell with PBA additive delivered higher discharge capacity under -10 °C at 0.5 C (173.7 mAh g-1 vs. 111.1 mAh g-1 ). Based on the improvement of NCM811 interphasial properties by additive PBA, the capacity retention of NCM811/graphite full-cell was enhanced from 49 % to 65 % after 200 cycles.

11.
Front Biosci (Landmark Ed) ; 27(12): 319, 2022 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-36624939

RESUMEN

OBJECTIVE: The aim of this study was to explore the effect of concentrated growth factor (CGF) on the wound healing potential of human epidermal cells (HaCaT) in vitro and in vivo. METHODS: CGF was extracted from venous blood using the centrifugal separation method. The CGF-conditioned medium was prepared from CGF gel immersed in Dulbecco's Modified Eagle medium. Crystal violet staining and wound healing assay were used to evaluate the proliferation and migration of HaCaT cells, respectively. Lipopolysaccharide (LPS) was used to test the anti-inflammatory function of CGF. An ELISA kit was employed to detect the concentration of growth factors and interleukins in CGF medium. mRNA and protein levels of angiogenic biomarkers (Angiopoietin-1 (ANGPT-1), vascular endothelial growth factor-A (VEGF-A) and Angiopoietin-2 (ANGPT-2) ) were determined by quantitative polymerase chain reaction (qPCR) and Western blot, respectively. A dorsal excisional wound model was recruited to test the wound healing effect of CGF in mice. RESULTS: Three-day treatment of HaCaT cells with CGF significantly promoted cell proliferation, which was followed by an increase in Vascular Endothelial Growth Factor (VEGF) and Fibroblast Growth Factor (FGF) levels in the medium. Cytokines (IL-6, IL-8 and TNF-α) were increased in LPS-stimulated HaCaT cells after 3 days, and CGF slightly inhibited the mRNA expression of these cytokines. The RAS signaling pathway was activated upon CGF treatment. Both RAS knockdown and an inhibitor of RAS (zoledronic acid) could block the migration of HaCaT cells after CGF treatment. Protein expressions of CD31, ANGPT-1, and VEGF-A were up-regulated in a dose-dependent manner upon CGF exposure. The protein level of ANGPT-2 was down-regulated after CGF treatment. CGF could promote wound healing in vivo, as demonstrated using the full skin defect model in nude mice. CONCLUSIONS: CGF was shown to promote wound repair in vitro and in vivo. The RAS cell signaling pathway was responsible for CGF stimulating the wound healing potential of HaCaT cells.


Asunto(s)
Células HaCaT , Factor A de Crecimiento Endotelial Vascular , Ratones , Humanos , Animales , Factor A de Crecimiento Endotelial Vascular/genética , Lipopolisacáridos/farmacología , Ratones Desnudos , Péptidos y Proteínas de Señalización Intercelular/genética , Citocinas , Factores de Crecimiento Endotelial Vascular/farmacología , Transducción de Señal , Proliferación Celular , Cicatrización de Heridas , ARN Mensajero
12.
Ann Transl Med ; 9(19): 1501, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34805363

RESUMEN

BACKGROUND: Preoperative assessment clinics have great benefits in reducing surgical cancellations, saving hospital resources and improving patient satisfaction. However, previous studies did not focus on patients with comorbidities. With advancements in medicine and aging population, the number of elderly patients with multiple comorbidities is increasing. This study was designed to assess the effectiveness of a preoperative assessment clinic for patients with multiple comorbidities. METHODS: This prospective, observational study enrolled patients with multiple comorbidities from Nov 1, 2019 to Oct 31, 2020 in a tertiary teaching hospital in China. Patients either visited the preoperative assessment clinic before admission or received an anesthesia consultation after admission. The impact of clinic visits on operating room cancellations, length of hospital stay before surgery, length of hospital stay after surgery, major postoperative complications, incidence of postoperative intensive care unit (ICU) admission, readmission to any hospital within 30 days after surgeries and total in-hospital costs were analyzed. RESULTS: A total of 326 eligible cases were included. Eighty-seven of 108 cases who visited the clinic before admission were scheduled for selective surgeries. In all, 218 patients received an anesthesia consultation after admission. The cancellation rate in the inpatient group was 7.80%, while no surgeries were cancelled in preclinic group (P=0.016). A preoperative assessment clinic visit statistically decreased the length of in-hospital stays before surgery from 93.02 to 76.11 h (P=0.010). After propensity score matching, significant differences in operating room cancellations (0 vs. 6.48%; P=0.015) and length of stay before surgery (76.11 vs. 92.22 h; P=0.038) persisted between two groups. No significant differences between the two groups were found in terms of prognosis, including major postoperative complications, incidence of postoperative ICU admissions, and readmissions to any hospital within 30 days (P>0.05). CONCLUSIONS: Among patients with comorbidities undergoing major surgeries, a preoperative assessment clinic visit was more efficient than an anesthesia consultation after admission. These findings may provide impetus for the opening of preoperative assessment clinics for critical patients in China.

13.
ACS Omega ; 6(46): 31330-31338, 2021 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-34841176

RESUMEN

The operating voltage of lithium-nickel-manganese oxide (LiNi0.5Mn1.5O4, LNMO) cathodes far exceeds the oxidation stability of the commercial electrolytes. The electrolytes undergo oxidation and decomposition during the charge/discharge process, resulting in the capacity fading of a high-voltage LNMO. Therefore, enhancing the interphasial stability of the high-voltage LNMO cathode is critical to promoting its commercial application. Applying a film-forming additive is one of the valid methods to solve the interphasial instability. However, most of the proposed additives are expensive, which increases the cost of the battery. In this work, a new cost-efficient film-forming electrolyte additive, 4-trifluoromethylphenylboronic acid (4TP), is adopted to enhance the long-term cycle stability of LNMO/Li cell at 4.9 V. With only 2 wt % 4TP, the capacity retention of LNMO/Li cell reaches up to 89% from 26% after 480 cycles. Moreover, 4TP is effective in increasing the rate performance of graphite anode. These results show that the 4TP additive can be applied in high-voltage LIBs, which significantly increases the manufacturing cost while improving the battery performance.

14.
World J Clin Cases ; 9(18): 4797-4802, 2021 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-34222450

RESUMEN

BACKGROUND: Management of chronic refractory wounds is one of the toughest clinical challenges for surgeons. Because of poor blood supply, less tissue coverage, and easy exposure, the lower leg is a common site for chronic refractory wounds. The current therapeutic regimens often lead to prolonged hospital stay and higher healthcare costs. Concentrated growth factor (CGF) is a novel blood extract that contains various growth factors, platelets, and fibrins to promote wound healing process. However, there has been little research reported on the treatment of lower extremity wounds with CGF. CASE SUMMARY: A 37-year-old man, without any past medical history, presented an ulcerated chronic wound on his right lower leg. The skin defect exhibited clear boundaries, with a size of 2.0 cm × 3.5 cm. The depth of wound was up to the layer of deep fascia. Staphylococcus aureus was detected by bacterial culture. The final diagnosis was right lower extremity ulcers with infection. Cefathiamidine, silver sulfadiazine, and mupirocin cream were applied to control the infection. CGF gel was prepared from the patient's blood sample, and was used to cover the wound after thorough debridement. The skin wound was successfully healed after three times of CGF treatment. CONCLUSION: CGF displays an excellent wound healing promoting effect in patients with lower-extremity chronic refractory wounds.

15.
J Phys Chem Lett ; 12(18): 4327-4338, 2021 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-33929192

RESUMEN

Nickel-rich oxide/graphite cells under high voltage operation provide high energy density but present short cycle life because of the parasitic electrolyte decomposition reactions. In this work, we report a novel electrolyte additive, N,O-bis(trimehylsilyl)-trifluoroacetamide (NOB), which enables nickel-rich oxide/graphite cells to operate stably under high voltage. When evaluated in a nickel-rich oxide-based full cell, LiNi0.5Co0.2Mn0.3O2 (NCM523)/graphite using a carbonate electrolyte, 1 wt % NOB provides the cell with capacity retention improved from 38% to 73% after 100 cycles at 1C under 4.5 V. It is found that NOB is able to eliminate hydrogen fluoride in the electrolyte. The radicals resulting from the interaction of NOB with the fluoride ion can be preferentially oxidized on the cathode compared with the electrolyte solvents, with its reaction products constructing N-containing interphases simultaneously on the cathode and anode, which suppress the parasitic electrolyte decomposition reactions, leading to the significantly improved cycle stability of nickel-rich oxide/graphite cells under high voltage.


Asunto(s)
Grafito/química , Níquel/química , Óxidos/química , Acetamidas/química , Suministros de Energía Eléctrica , Técnicas Electroquímicas , Electrodos , Electrólitos/química , Oxidación-Reducción , Solventes/química , Compuestos de Trimetilsililo/química
16.
Int J Hydrogen Energy ; 46(18): 10783-10788, 2021 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-33737761

RESUMEN

In this work, we report on the creation of a black copper via femtosecond laser processing and its application as a novel electrode material. We show that the black copper exhibits an excellent electrocatalytic activity for hydrogen evolution reaction (HER) in alkaline solution. The laser processing results in a unique microstructure: microparticles covered by finer nanoparticles on top. Electrochemical measurements demonstrate that the kinetics of the HER is significantly accelerated after bare copper is treated and turned black. At -0.325 V (v.s. RHE) in 1 M KOH aqueous solution, the calculated area-specific charge transfer resistance of the electrode decreases sharply from 159 Ω cm2 for the untreated copper to 1 Ω cm2 for the black copper. The electrochemical surface area of the black copper is measured to be only 2.4 times that of the untreated copper and therefore, the significantly enhanced electrocatalytic activity of the black copper for HER is mostly a result of its unique microstructure that favors the formation and enrichment of protons on the surface of copper. This work provides a new strategy for developing high-efficient electrodes for hydrogen generation.

17.
Nanotechnology ; 32(19): 192002, 2021 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-33498035

RESUMEN

Lithium/sulfur (Li/S) batteries have emerged as one of the most promising next-generation energy storage systems with advantages of high theoretical energy density, low cost and environmental friendliness. However, problems regarding to severe shuttle effect of soluble polysulfide, poor electronic/ionic conductor of solid charged/discharged products (S8 and Li2S), and fatal swell of volume along with the growth of Li dendrites greatly deteriorate the sulfur utilization and capacity retention during extended charge-discharge cycles. With advantages of high nitrogen content, lithiophilic modulation and tunable charge density and charge transfer, carbon nitride (g-C3N4) has played a positive role in restricting the shuttle effects and dendrite formation. This minireview mainly discusses these research achievements of g-C3N4 in Li/S batteries, aiming to provide a basic understanding and direct guidance for further research and development of functionalized g-C3N4 materials in electrical energy storage. The two-dimensional (2D) structure of g-C3N4 with abundant hierarchical pores improves its accommodation capacity for sulfur by effectively confining the lithium polysulfides (LiPSs) into the pores, and provides favorable channels for ion diffusion. The rich nitrogen and carbon defects further offer more active sites for strongly adsorbing LiPSs and bridge electron transfer pathway at atomic scale for catalytic reactions to accelerate redox kinetics of Li/S conversion chemistry. Moreover, the features of lithiophilic wettability, high adsorption energy and densely distributed lithiophilic N of g-C3N4 provide a large number of adhesive sites for lithium cation (Li+) and disperse the nucleation sites to enable uniform nucleation and deposition of Li on the anode surface and to suppress formation and growth of Li dendrites. Finally, the g-C3N4 also effectively regulates the wettability between Li anode and solid inorganic electrolyte, and reduces the crystallinity of solid polymer electrolyte to enhance the Li+ migration ability and ionic conductivity.

20.
ACS Appl Mater Interfaces ; 12(30): 33719-33728, 2020 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-32608965

RESUMEN

Metallic lithium (Li) has great potential as an anode material for high-energy-density batteries due to its high specific capacity. However, the uncontrollable dendritic lithium growth on the metallic lithium surface limits its practical application owing to the instability of the solid electrolyte interphase (SEI). A tailored SEI composition/structure can mitigate or inhibit the lithium dendrites' growth, thereby enhancing the cyclability of the Li-metal anode. In this work, excellent cycling stability of lithium metal anodes was achieved by utilizing a novel dual-salt electrolyte based on lithium bis(fluorosulfonyl) imide (LiFSI) and lithium difluorobis(oxalato) phosphate (LiDFBOP) in carbonate solvents. By combining surface/microstructural characterization and computations, we reveal that the preferential reduction of LiDFBOP occurs prior to LiFSI and carbonate solvents and its reduction products (Li2C2O4 and P-O species) bind to LiF, resulting in a favorable compact and protective SEI on the Li electrodes. It was found that the improved oxidative stability was accompanied by reduced corrosion of the current collector. A Li/Li symmetrical cell with a designed dual-salt electrolyte system exhibits stable polarization voltage over 1000 h of cycle time. In addition, the LiFSI-LiDFBOP advantage of this dual-salt electrolyte system enables the Li/LiFePO4 cells with significantly enhanced cycling stability. This work demonstrates that constructing a tailored SEI using a dual-salt electrolyte system is vital for improving the interfacial stability of lithium metal batteries.

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