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1.
Nanotechnology ; 34(23)2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-36877999

RESUMO

Micro/nano electronic devices heat dissipation depends heavily on the thermal interface materials (TIMs). Despite notable progress, it is hard to efficaciously enhance the thermal properties of the hybrid TIMs with high-load additives due to an absence of effective heat transfer routes. Herein, the low content of three-dimensional (3D) graphene with interconnected networks is adopted as the additive to improve the thermal properties of epoxy composite TIMs. The thermal diffusivity and thermal conductivity of the as-prepared hybrids were dramatically improved by constructing thermal conduction networks after adding 3D graphene as fillers. The 3D graphene/epoxy hybrid's optimal thermal characteristics were observed at 1.5 wt% of 3D graphene content, corresponding to a maximum enhancement of 683%. Besides, heat transfer experiments were further performed to determine the superb heat dissipation potential of the 3D graphene/epoxy hybrids. Moreover, the 3D graphene/epoxy composite TIM was also applied to high-power LED to improve heat dissipation. It effectively reduced the maximum temperature from 79.8 °C to 74.3 °C. These results are beneficial for the better cooling performance of electronic devices and provide useful guidelines for advancing the next-generation TIMs.

2.
Adv Sci (Weinh) ; 10(9): e2207470, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36737850

RESUMO

The targeted synthesis of manganese phosphides with target phase remains a huge challenge because of their various stoichiometries and phase-dependent physicochemical properties. In this study, phosphorus-rich MnP, manganese-rich Mn2 P, and their heterostructure MnP-Mn2 P nanoparticles evenly dispersed on porous carbon are accurately synthesized by a convenient one-pot heat treatment of phosphate resin combined with Mn2+ . Moreover, their electrochemical properties are systematically investigated as sulfur hosts in lithium-sulfur batteries. Density functional theory calculations demonstrate the superior adsorption, catalysis capabilities, and electrical conductivity of MnP-Mn2 P/C, compared with MnP/C and Mn2 P/C. The MnP-Mn2 P/C@S exhibits an excellent capacity of 763.3 mAh g-1 at 5 C with a capacity decay rate of only 0.013% after 2000 cycles. A phase evolution product (MnS) of MnP-Mn2 P/C@S is detected during the catalysis of MnP-Mn2 P/C with polysulfides redox through in situ X-ray diffraction and Raman spectroscopy. At a sulfur loading of up to 8 mg cm-2 , the MnP-Mn2 P/C@S achieves an area capacity of 6.4 mAh cm-2 at 0.2 C. A pouch cell with the MnP-Mn2 P/C@S cathode exhibits an initial energy density of 360 Wh kg-1 .

3.
J Colloid Interface Sci ; 628(Pt B): 513-523, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36007416

RESUMO

The development of electrocatalyst with efficient and stability for water oxidation is the key to enhance the efficiency of water electrolysis. Interface engineering can modify the local electronic structure of active sites, which is one of the important strategy to enhance catalytic activity. Herein, we synthesized NiMoSx heterostructure nanorods by simple hydrothermal method. The self supporting electrode of NiMoSx heterostructure nanorods grown in situ on nickel foam can reduce the indirect contact resistance between the substrate and the catalyst, and promote the timely release of bubbles produced by the oxygen evolution reaction. The heterogeneous interface in NiMoSx can provide abundant electroactive centers and optimize the adsorption energy of active intermediates. NiMoSx heterostructure nanorods showed excellent oxygen evolution catalytic activity (η100 = 279 mV, η1000 = 436 mV, Tafel slope b = 72.3 mV dec-1) and more than 200 hours of sustainable durability in 1 M KOH. When NiMoSx heterostructure nanorods are used as anode materials for water electrolysis, the electrolytic cell could obtain 10 mA cm-2 at 1.48 V. The current research results not only show that NiMoSx nanostructure is an excellent oxygen evolution electrocatalyst, At the same time, it also provides a valuable interface regulation method for the design of high-performance heterostructure electrocatalyst.

4.
Nano Lett ; 22(14): 5795-5802, 2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35820175

RESUMO

Flexible power sources are critical to achieve the wide adoption of portable and wearable electronics. Herein, a facile and general strategy of fabricating a fibrous electrode was developed by 3D active coating technology, in which a stepping syringe with electrode paste was synchronously injected onto a rotating conductive wire, distinguished from the conventional direct-write 3D printing without a current collector. A series of such electrodes with different coating weight can be fabricated accurately and efficiently by adjusting critical process parameters following a set of derived equations. The demonstrated fibrous Zn-MnO2 battery with a high commercial ε-MnO2 loading of 14.9 mg cm-2 onto a stainless steel wire shows a reasonable energy density of 108 mWh cm-3, while the fiber-shaped supercapacitor with commercial porous graphene exhibits a high capacitance of 142.9 F g-1 and good durability for bending 10,000 cycles. This work constructs a bridge between materials and fiber-shaped electrodes for flexible energy storage devices.

5.
Small ; 18(10): e2105329, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35023622

RESUMO

Nonprecious group metal (NPGM)-based single atom catalysts (SACs) hold a great potential in electrocatalysis and dopant engineering has been extensively exploited to boost their catalytic activity, while the coordination environment of dopant, which also significantly affects the electronic structure of SACs, and consequently their electrocatalytic performance, have been largely ignored. Here, by adopting a precursor modulation strategy, the authors successfully synthesize single cobalt atom catalysts embedded in nitrogen-doped carbon, Co-N/C, with similar overall Co and N concentrations but different N types, that is, pyridinic N (NP ), graphitic N (NG ), and pyrrolic N (NPY ). Co-N/C with the Co-N4 moieties coordinated with NG displays far superior activity for oxygen reduction (ORR) and evolution reactions, and superior activity and stability in both zinc-air batteries and proton exchange membrane fuel cells. Density functional theory calculation indicates that coordinated N species in particular NG functions as electron donors to the Co core of Co-N4 active sites, leading to the downshift of d-band center of Co-N4 and weakening the binding energies of the intermediates on Co-N4 sites, thus, significantly promoting catalytic kinetics and thermodynamics for ORR in a full pH range condition.

6.
J Colloid Interface Sci ; 607(Pt 2): 1411-1423, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34587528

RESUMO

Herein, we introduce a facile approach to synthesize a unique class of Pt-M (M = Ni, Co) catalysts with a nanoflower structure for boosting both oxygen reduction reaction (ORR) and methanol oxidation reaction (MOR). By controlling the surface-active agents, we modified the functional groups surrounding the Pt atoms, tuned the alloying of Pt and the transition metals Ni and Co, and prepared two different kinds of nanodendrites. Their successful synthesis depends on the selection and amount of surfactants (hexadecyltrimethylammonium bromide (CTAB), Polyvinylpyrrolidone (PVP)). Besides, by controlling reaction time, we also explored the forming procedures for Pt-Co globularia nanodendrite (Pt-Co GND) and Pt-Ni petalody nanodendrite (Pt-Ni PND). Our investigation highlights the importance of complex nanoarchitecture, which enables surface and interface modification to achieve excellent catalytic performance in fuel cell electrocatalysis. The characterization of the as-prepared catalysts reveals a high electrochemical surface area and mass activity (2041 mAmgPt-1and 950 mAmgPt-1 for Pt-Co GND and Pt-Ni PND, respectively, for ORR). Furthermore, Pt-Co GND showed a high MOR activity, with a mass activity value recorded at 1615 mAmgPt-1 which is far superior to that for Pt/C. Moreover, both catalysts retain high activity after accelerated durability tests (ADTs). The electron transfer number was calculated by performing the rotating ring-disk electrode (RRDE) measurements. Due to abundant active sites of Pt, both Pt-Co GND and Pt-Ni PND exhibit a 4e- pathway for ORR with electron transfer number of >3.95.

7.
J Colloid Interface Sci ; 610: 213-220, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34922077

RESUMO

Herein, a novel Ru-doped bimetal phosphide (Ru-NiCoP) heterostructure electrocatalyst on Ni foam is successfully synthesized through a multi-step hydrothermal reaction, ion exchange, and phosphorization method for efficient overall water splitting in alkaline media. The doping of Ru and P can effectively optimize the electronic structure and expose more active sites. The unique 3D interconnected nanowires not only ensures the uniform distribution of Ru coupled with NiCoP, but also endows the Ru-NiCoP/NF with the large ECSA, the fast electron transport and the favorable reaction kinetics attributes. Benefiting from the compositional and structural advantages, Ru-NiCoP/NF catalyst exhibits significantly enhancedcatalytic activities along with excellent stability, only needing 32.3 mV at 10 mA cm-2 for HER and 233.8 mV at 50 mA cm-2 for OER. In particular, when Ru-NiCoP/NF is employed as both cathode and anode electrodes,a small voltage of 1.50 V is required to reach 30 mA cm-2for overall water splittingwith an impressive stability. This study provides an alternative strategyon the design and development of high performance catalysts foroverall water splittingand other energy conversion fields.

8.
Chem Sci ; 12(45): 15054-15060, 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34909145

RESUMO

Herein, a chemical-vapor deposition-like strategy was developed for the synthesis of versatile core-shell transition metal sulfide (TMS)@carbon nanowires with chemically-bonded heterostructures and significantly improved electrochemical performance. The morphological evolution observations revealed the simultaneous growth of TMS nanowires and their bonding with an ultrathin carbon layer. The resulting core-shell heterostructured nanowires possessed notable advantages, including fast ion/electron diffusion rates, improved conductivity, and chemical/mechanical stability, thereby leading to remarkable reversible capacity, rate capability, and cycling stability for Na-ion storage applications. The in situ transmission electron microscopy and in situ X-ray diffraction studies for FeS@C demonstrated the crystalline phase evolution between hexagonal and tetragonal FeS species during the electrochemical charging/discharging process, clearly indicating the excellent Na-ion storage performance of FeS@C nanowires. This work provides a new methodology for achieving 1D core-shell nanoarchitectures, while elucidating the electrochemical reaction mechanism underlying Na-ion storage in TMS materials.

9.
J Colloid Interface Sci ; 604: 894-902, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34311264

RESUMO

Committed to improving the utilization efficiency of Pt atoms and accurately controlling the morphology and composition of nanocatalysts to boost the Pt-based catalyst performance has become the focus of research. Herein, the PtRhNi truncated triangular nanoflakes (TA-NFs) catalyst with a unique PtRh-rich surface structure was successfully prepared by an effective one-pot synthetic method based on the galvanic replace reaction. The freestanding 2D nanostructure of PtRhNi TA-NFs, intrinsically possessing much high specific surface area and surface atomic, and the PtRh-rich characteristics of the surface is undoubtedly the most feasible model to simultaneously achieve high atom utilization. Benefiting from this novel structure, the as-obtained PtRhNi TA-NFs nanocatalyst exhibits excellent performance for ORR and MOR, delivering a mass activity of 0.92 A mgpt-1 for ORR, which is 2.03, 1.64, and 6.9-fold higher than that of PtRhNi nanoparticls (NPs), PtNi truncated triangle nanoflakes (TA-NFs) and commercial Pt/C, respectively. In addition, after 20 k cycles ADT test, PtRhNi TA-NFs show only 10 mV negative shift of half-wave potential and retain 70% of initial value of mass activity. Furthermore, a mass activity is 1.28 A mgpt-1 is achieved after applying this unique nanocatalyst for MOR, which is 1.28,1.5, and 2.6 times higher than that of PtRhNi NPs, PtNi TA-NFs and Pt/C, respectively. Impressively, the PtRhNi TA-NFs nanocatalyst shows an ultrahigh stability even after 2 k cycles ADT measurement in acid solution, and the mass activity is only drop 2% of initial value. This work provides a new strategy to synthesis high-performance of bifunction Pt-based electrocatalyst for ORR and MOR fuel cells.

10.
iScience ; 24(6): 102547, 2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34142052

RESUMO

The Ni-Fe battery is a promising alternative to lithium ion batteries due to its long life, high reliability, and eco-friendly characteristics. However, passivation and self-discharge of the iron anode are the two main issues. Here, we demonstrate that controlling the valence state of the iron and coupling with carbon can solve these problems. We develop a mesostructured carbon/Fe/FeO/Fe3O4 hybrid by a one-step solid-state reaction. Experimental evidence reveals that the optimized system with three valence states of iron facilitates the redox kinetics, while the carbon layers can effectively enhance the charge transfer and suppress self-discharge. The hybrid anode exhibits high specific capacity of 604 mAh⋅g-1 at 1 A⋅g-1 and high cyclic stability. A Ni-Fe button battery is fabricated using the hybrid anode exhibits specific device energy of 127 Wh⋅kg-1 at a power density of 0.58 kW⋅kg-1 and maintains good capacity retention (90%) and coulombic efficiency (98.5%).

11.
Nanotechnology ; 32(35)2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34034237

RESUMO

Herein, we demonstrate a distinctive energy harvesting method that electricity can be generated from the ionic solution flowing through the interstices between packed three-dimensional graphene powders. A constructed electrokinetic nanogenerator with an effective flow area of ∼0.34 cm2can generate a large current of 91.33 nA under 10-6M NaCl solution with a flow rate of 0.4 ml min-1, corresponding to a maximum power density of 0.45µW m-2. Besides, it shows a good linear relationship between the streaming current and the flow rate, suggesting that it could be used as a self-powered micro-flowmeter. These results provide a convenient way for clean energy harvesting and show a bright future for self-powered systems.

12.
ACS Appl Mater Interfaces ; 13(18): 21390-21400, 2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-33928780

RESUMO

Polyanionic cathode materials that have high energy density and good temperature adaptability are in high demand for practical applications in sodium-ion batteries (SIBs). In this study, a scalable spray-drying strategy has been proposed to construct interconnected conductive networks composed of amorphous carbon and reduced graphene oxide in Na3MnZr(PO4)3 microspheres (NMZP@C-rGO). The dual-carbon conductive networks provide fast electron migration pathways in the microspheres. Moreover, they significantly increase the porosity and specific surface area of the microspheres, which are conducive to accommodating the volume change and improving the electrode/electrolyte contact interface and the contribution of the pseudocapacitance effect to achieve fast sodium storage. As a result, NMZP@C-rGO exhibits excellent rate performance (50.9 mAh g-1 at 50C and 30 °C, 35.4 mAh g-1 at 50C and -15 °C) and long-term cycling stability (capacity retentions of 97.4 and 79.6% after 1500 cycles at 30 and -15 °C, respectively) in a wide temperature range.

13.
Small ; 17(18): e2007915, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33749142

RESUMO

To get carbon electrode with both excellent gravimetric and volumetric capacitances at high mass loadings is critical to supercapacitors. Herein, cracked defective graphene nanospheres (GNS) well meet above requirements. The morphology and structure of the GNS are controlled by polystyrene sphere template/glucose ratio, microwave heating time, and Fe content. The typical GNS with specific surface area of 2794 m2 g-1 , pore volume of 1.48 cm3 g-1 , and packing density of 0.74 g cm-3 performs high gravimetric and volumetric capacitances of 529 F g-1 and 392 F cm-3 at 1A g-1 with a capacitance retention of 62.5% at 100 A g-1 in a three-electrode system in 6 mol L-1 KOH aqueous electrolyte. In a two-electrode system, the GNS possesses energy density of 18.6 Wh kg-1 (13.8 Wh L-1 ) at the power density of 504 W kg-1 , which is higher than all reported pure carbon materials in gravimetric energy density and higher than all reported heteroatom-doped carbon materials in volumetric energy density, in aqueous solution, as far as it is known. A structural feature of carbon materials that possess both high energy density and high power density is pointed out here.

14.
Nanoscale ; 13(5): 2963-2971, 2021 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-33508049

RESUMO

Lithium-sulfur (Li-S) batteries with high energy density, which show great application potential in flexible electronic products, have attracted a lot of research enthusiasm. However, the low utilization of sulfur and shuttle effect limit the application of Li-S batteries. Materials with a void structure and high conductivity can be used as a sulfur host to overcome these issues. Herein, a flexible MXene-coated textile fabric electrode (MF@Ti3C2Tx/S) is designed by integrating the MXene-coated textile fabric (MF) with in situ sulfur loaded MXene nanosheets (Ti3C2Tx/S). The MF provides a flexible 3D conductive framework, which is covered with Ti3C2Tx/S nanosheets to form the layer-by-layer structure. This unique structure not only provides enough space for volume expansion to maintain the structural stability in the electrochemical process, but also promotes the physical encapsulation and chemical adsorption of lithium polysulfides (LiPSs). Consequently, the MF@Ti3C2Tx/S50 electrode exhibits a high initial capacity of 916 mA h g-1 at 1C and an ultralong-term cycling stability of 674 mA h g-1 at 1C after 1000 cycles. Furthermore, this electrode also exhibits excellent rate performance at a high energy density (290 mA h g-1 at 5C after 800 cycles). A pouch cell is prepared by using the MF@Ti3C2Tx/S50 electrode and shows excellent cycle performances at different bending angles, which indicates that this study is valuable in the field of flexible energy storage. This work provides a new concept design for flexible Li-S batteries, which have great application potential as wearable and portable electronic devices.

15.
ACS Appl Mater Interfaces ; 13(1): 1903-1913, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33351607

RESUMO

The initial growth mode of oxide on alloy plays a decisive role in the development of protective oxide scales on metals and alloys, which is critical for their functionality for high temperature applications. However, the atomistic mechanisms dictating that the oxide growth remain elusive due to the lack of direct in situ observation of the initial oxide nucleation and growth at atomic-scale. Herein, we employed environmental transmission electron microscopy and the first-principles calculations to elucidate the initial atomic process of nickel-chromium (Ni-Cr) alloy oxidation. We directly revealed three different oxide growth modes of initial NiO islands on Ni-Cr alloy upon oxidation by O2, which result in distinct crystallography and morphology. The multimode oxide growth leads to irregular-shaped oxides, which is shown to be sensitive to the local mass transport. This localization of oxide growth mode is also demonstrated by the identified vigorous competence in oxide growth and thus shown to be kinetically controlled. The concept exemplified here provides insights into the oxide formation and has significant implications in other material and chemical processes involving oxygen gas, such as corrosion, heterogeneous catalysis, and ionic conduction.

16.
Nanoscale ; 12(47): 24070-24078, 2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33241831

RESUMO

Improving the utilization of Ir electrocatalysts for the oxygen evolution reaction (OER) to significantly reduce their loading is essential for low-cost hydrogen production in proton exchange membrane water electrolysis. Herein, IrCo hollow nanospheres featuring a novel structure with ultrathin continuous shells which have only eleven atomic layers (2.26 nm) were synthesized by a facile sequential reduction route using NaBH4 as a reducing agent at room temperature. It is revealed that the key intermediate in the formation of hollow nanospheres is amorphous cobalt boride formed between Co2+ and NaHB4 in the first reducing step. The average diameter of the IrCo nanospheres was found to be 73.71 nm with the atomic ratio of 47.1% and 52.9% for Co and Ir, respectively. The IrCo hollow nanospheres exhibit highly efficient OER activity and long-term durability with a low overpotential of 284 mV at 10 mA cm-2 (32.5 µgIr cm-2) and a high mass activity of 8.49 A mg-1 (5.7 times higher than that of commercial IrO2 (1.49 A mg-1) at 1.7 V. The performance is also proved using an overall water splitting device with the overpotential of 318 mV to achieve 10 mA cm-2 as well as a 17 mV shift at 5 mA cm-2 after 14 h. This improvement is critically attributed to the advantages of the hollow structure, ultrathin continuous shells which are oxidized into IrOxin situ and strong lattice strain effects induced by the specific hollow structure and alloying Co into Ir crystal lattices (1.6% against metallic iridium). These characteristics endow the hollow nanospheres with great potential to minimize the Ir loading dramatically for practical applications, compared to other previously reported structures like nanoparticles, nanoneedles and nanowires.

17.
Small ; 16(45): e2003001, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33078568

RESUMO

Rational structure and morphology design are of great significance to realize excellent Na storage for advanced electrode materials in sodium-ion batteries (SIBs). Herein, a cube-like core/shell composite of single MnS nanocubes (≈50 nm) encapsulated in N, S co-doped carbon (MnS@NSC) with strong CSMn bond interactions is successfully prepared as outstanding anode material for SIBs. The carbon shell significantly restricts the expansion of the MnS volume in successive sodiation/desodiation processes, as demonstrated by in situ transmission electron microscopy (TEM) of one single MnS@NSC nanocube. Moreover, the in situ generated CSMn bonds between the MnS core and carbon shell play a significant role in improving the Na-storage stability and reversibility of MnS@NSC, as revealed by in situ Raman and TEM. As a result, MnS@NSC exhibits a high reversible specific capacity of 594.2 mAh g-1 at a current density of 100 mA g-1 and an excellent rate performance. It also achieves a remarkable cycling stability of 329.1 mAh g-1 after 3000 charge/discharge cycles at 1 A g-1 corresponding to a low capacity attenuation rate of 0.0068% per cycle, which is superior to that of pristine MnS and most of the reported Mn-based anode materials in SIBs.

18.
Adv Mater ; 32(36): e2002822, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32705724

RESUMO

Engineering novel Sn-based bimetallic materials could provide intriguing catalytic properties to boost the electrochemical CO2 reduction. Herein, the first synthesis of homogeneous Sn1- x Bix alloy nanoparticles (x up to 0.20) with native Bi-doped amorphous SnOx shells for efficient CO2 reduction is reported. The Bi-SnOx nanoshells boost the production of formate with high Faradaic efficiencies (>90%) over a wide potential window (-0.67 to -0.92 V vs RHE) with low overpotentials, outperforming current tin oxide catalysts. The state-of-the-art Bi-SnOx nanoshells derived from Sn0.80 Bi0.20 alloy nanoparticles exhibit a great partial current density of 74.6 mA cm-2 and high Faradaic efficiency of 95.8%. The detailed electrocatalytic analyses and corresponding density functional theory calculations simultaneously reveal that the incorporation of Bi atoms into Sn species facilitates formate production by suppressing the formation of H2 and CO.

19.
ACS Appl Mater Interfaces ; 11(43): 39809-39819, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31596068

RESUMO

Electrochemical water-splitting reactions (hydrogen evolution reaction (HER) and oxygen evolution reaction (OER)) and oxygen redox reactions (oxygen reduction reaction (ORR) and OER) are core processes for electrochemical water-splitting devices, rechargeable metal-air batteries, and regenerative fuel cells. Developing highly efficient non-noble multifunctional catalysts in the same electrolyte is an open challenge. Herein, efficient Co-N-C electrocatalysts with a mixed structure comprising Co-N moieties and Co nanoparticles encapsulated in a N-doped carbon layer were prepared via pyrolysis of a new structure of Co-coordinated bis(imino)pyridine polymer constructed by 2,6-diacetylpyridine and 3,3'-diaminobenzidine. Results demonstrate that Co ion sources have a remarkable impact on the final Co-N-C performance. The Co-N-C catalyst prepared using cobalt acetate as a precursor displays remarkable overall multifunctional performance. It needs only a cell voltage of 1.66 V (obtained from the half-cell test) for the water-splitting reaction (HER/OER) to reach 10 mA·cm-2 in 1.0 M KOH, and the overall oxygen redox activity (OER/ORR) is 0.72 V in 0.1 M KOH, outperforming the reported nonprecious metal catalysts. The excellent activity is attributable to the synergistic effects between active sites with encapsulated metallic Co for HER and OER and Co-N moieties for ORR.

20.
ACS Appl Mater Interfaces ; 11(5): 4922-4929, 2019 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-30632734

RESUMO

Harvesting energy from the ambient environment provides great promise in the applications of micro/nanodevices and self-powered systems. Herein, we report a novel energy-scavenging method where an ionic solution infiltrating into a three-dimensional graphene (3DG) membrane can spontaneously generate electricity under ambient conditions. A constructed 3DG nanogenerator (3DGNG) with an effective size of 0.5 × 2 cm can produce a continuous voltage of ∼0.28 V and a remarkable output current of ∼62 µA. The voltage is higher than those generated from the interaction between water and carbon nanomaterials in previous research typically in the range of microvolts to millivolts. Moreover, we demonstrate the potential application of the 3DGNG by illuminating a liquid crystal display (LCD) directly with 10 3DGNGs in series. These results present a novel avenue for energy harvesting and show bright potential applications in small devices and self-powered systems.

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