The utilization of Ni(OH)2 as a pseudocapacitive material for high performance supercapacitors is hindered by its low electrical conductivity and short cycle life. A coaxial ternary hybrid material comprising of amorphous Ni(OH)2 deposited on multiwalled carbon nanotubes wrapped with conductive polymer (poly (3,4-ethylenedioxythiophene)-poly(styrenesulfonate)) is demonstrated. A thin layer of disordered amorphous Ni(OH)2 is deposited by an effective “coordinating etching and precipitating” method, resulting in an ultrahigh specific capacitance of 3262 F g−1 at 5 mV s−1 and excellent rate capability (71.9% capacitance retention at 100 mV s−1). More importantly, the polymer layer prevents the degradation of the nanostructure and dis­solution of Ni ion during repeated charge–discharge cycling for 30 000 cycles, a phenomenon which often plagues Ni(OH)2 nanomaterials. Using the ternary Ni(OH)2 hybrid and the reduced graphene oxide/carbon nanotube hybrid as the positive and negative electrodes, respectively, the assembled asymmetric supercapacitors exhibit high energy density of 58.5 W h kg−1 at the power density of 780 W kg−1 as well as long cycle life (86% capacitance retention after 30 000 cycles). The ternary hybrid architecture design for amorphous Ni(OH)2 can be regarded as a general approach to obtain pseudocapacitive materials for supercapacitors with both high energy density, excellent rate capability, and long cycle life.

Ternary hybrids of amorphous nickel hydroxide-carbon nanotube-conducting polymer for supercapacitors with high energy density, excellent rate capability, and long cycle life

The formation of temporal dissipative Kerr solitons in microresonators driven by a continuous-wave laser enables the generation of coherent, broadband, and spectrally smooth optical frequency combs as well as femtosecond pulse sources with compact form factors. Here we report the observation of a Raman-induced soliton self-frequency shift for a microresonator dissipative Kerr soliton also referred to as the frequency-locked Raman soliton. In amorphous silicon nitride microresonator-based single soliton states the Raman effect manifests itself by a spectrum that is sech^{2} in shape and whose center is spectrally redshifted from the continuous wave pump laser. The shift is theoretically described by the first-order shock term of the material's Raman response, and we infer a Raman shock time of ∼20  fs for amorphous silicon nitride. Moreover, we observe that the Raman-induced frequency shift can lead to a cancellation or overcompensation of the soliton recoil caused by the formation of a coherent dispersive wave. The observations are in agreement with numerical simulations based on the Lugiato-Lefever equation with a Raman shock term. Our results contribute to the understanding of Kerr frequency combs in the soliton regime, enable one to substantially improve the accuracy of modeling, and are relevant to the understanding of the fundamental timing jitter of microresonator solitons.

Raman Self-Frequency Shift of Dissipative Kerr Solitons in an Optical Microresonator

Amorphous metal oxides (AMOs) have aroused great enthusiasm across multiple energy areas over recent years due to their unique properties, such as the intrinsic isotropy, versatility in compositions, absence of grain boundaries, defect distribution, flexible nature, etc. Here, the materials engineering of AMOs is systematically reviewed in different electrochemical applications and recent advances in understanding and developing AMO-based high-performance electrodes are highlighted. Attention is focused on the important roles that AMOs play in various energy storage and conversion technologies, such as active materials in metal-ion batteries and supercapacitors as well as active catalysts in water splitting, metal-air batteries, and fuel cells. The improvements of electrochemical performance in metal-ion batteries and supercapacitors are reviewed regarding the enhancement in active sites, mechanical strength, and defect distribution of amorphous structures. Furthermore, the high electrochemical activities boosted by AMOs in various fundamental reactions are elaborated on and they are related to the electrocatalytic behaviors in water splitting, metal-air batteries, and fuel cells. The applications in electrochromism and high-conducting sensors are also briefly discussed. Finally, perspectives on the existing challenges of AMOs for electrochemical applications are proposed, together with several promising future research directions.

Research Advances of Amorphous Metal Oxides in Electrochemical Energy Storage and Conversion.

Two-dimensional Co3O4 thin sheets assembled by 3D interconnected nanoflake array framework structures with enhanced supercapacitor performance derived from coordination complexes

As one of the most promising candidates for supercapacitor electrodes, transition metal hydroxides usually suffer from the quick decay in capacity during cycling, mainly caused by the decrease of electroactive surface area resulting from the instability of microstructure/morphology upon fast and repeated charging/discharging. Herein, we fabricated a structure-stable Ni(OH)2 grown on Ni foam via in situ ion-exchange reaction with Mg(OH)2 as sacrificial substrate and effective dopant. The obtained hybrid Ni(OH)2 possesses nanosheet morphology, large surface area (220 m2/g) and achieves an unprecedented cycling stability with a 95% retention after 10 000 cycles. The asymmetric supercapacitors with the hybrid Ni(OH)2 exhibit superior supercapacitive performances with large capacity of 167 F/g and maximum energy density of 57.9 Wh/kg at power density of 1.58 kW/kg. Even at a standard power density of 4.0 kW/kg, a high energy density of 49.6 Wh/kg was achieved, making the hybrid Ni(OH)2 a promising candidate fo...

In-Situ-Grown Mg(OH)2-Derived Hybrid α-Ni(OH)2 for Highly Stable Supercapacitor

High-performance supercapacitor electrode based on amorphous mesoporous Ni(OH)2 nanoboxes

Photoluminescence and hydrogen storage properties of gallium nitride hexagonal micro-bricks

Silicon nitride microsprings with superelasticity are characterized using SEM, XRD, TEM and micro-Raman methods. The internal structure and the superelastic mechanism of silicon nitride microsprings are proposed through analyzing the variation of Raman peaks upon stretching gradually. During the stretching process, since all the vibrations are internal vibrations within the primitive unit cell, the basic structure has no changes and the residual stress never concentrates. The special structure of the fine grains and no sharp grain boundaries make the silicon nitride microsprings possess such good superelastic properties.

The superelastic mechanism of Si3N4 microsprings using micro-Raman spectroscopy.

We synthesized unexplored activator-Fe doped silicon oxynitride microwires by a simple CVD method. This microwire can generate SPP when induced by photons/electrons. It exhibits three significant features, a stable emission peak, the ability to act as a plasmon nonlinear laser and displays mutual light beams interference. The absorption and external quantum efficiency of the Fe doped silicon oxynitride are 73.2% and 51.8%, respectively. Upon controlling the O/N ratio, the emission band can be tuned from 670 nm to 735 nm.

Fe doped silicon oxynitride microwires: surface plasmon polariton enhanced fluorescence and tunable long-wavelength red-emission

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Yan Fu

Author Tools

Chat about Author

Papers

High-performance supercapacitor electrode based on amorphous mesoporous Ni(OH)2 nanoboxes

Photoluminescence and hydrogen storage properties of gallium nitride hexagonal micro-bricks

The superelastic mechanism of Si3N4 microsprings using micro-Raman spectroscopy.

Fe doped silicon oxynitride microwires: surface plasmon polariton enhanced fluorescence and tunable long-wavelength red-emission