The storage mechanism difference between amorphous and anatase as supercapacitors

Although TiO_(2)nanotubes is a promising electrode as supercapacitors due to its high energy density,easy synthesis and chemical stability,there are draw backs such as low conductivity and capacitance.Many studies concentrated on improving its electrochemical performance itself but little attention was payed to the reason of capacitance differences caused by its different crystal structures.Herein,we prepare amorphous and anatase TiO_(2)nanotubes and hydrogenated them by a simple electrochemical hydrogenation method to improve their conductivity and capacitance.And then study and compare their morphology and structure differences by SEM,TEM,XRD and BET.The results show that the pore size distribution,internal structure order and internal carrier concentration are the main reasons for their electrochemical performance differences.The microporous structure less than 2 nm in amorphous nanotubes act as a trap of electrolyte ions at current density larger than 0.1μA cm^(-2),leading to small charge and discharge capacitance.The long-range ordered crystal structure of anatase is more favorable for the orderly diffusion of carriers,reducing the inelastic scattering of carrier diffusion process and the electron hole-complexing probability,making anatase nanotubes exhibit higher coulomb efficiency and cycle stability than that of amorphous ones.

Research on 48 V Super Capacitor Micro Hybrid System with 12 V Power Supply Multiplexing Function

48 V lithium battery micro hybrid system is the most fuel economy vehicle which can be mass produced at present.However,with the irreversible internal resistance increase of the key component 48 V lithium battery,and the capacity continues to decline,the system performance deteriorate.Worst case could be the system not functional in the middle and later age of vehicle life cycle.This paper studies the feasibility of using 48 V super capacitor as the replacement to 48 V lithium battery,and uses a 12 V module of 48 V super capacitor as the traditional 12 V power supply,further reducing the number of components or reducing the demand for parts of 48 V micro hybrid system.This paper analyses the 48 V super capacitor micro hybrid system scheme,based on which a prototype is built,and carries out the vehicle comparative test.The results show that:(1)The performance of 48 V super capacitor micro hybrid system perform comparably with 48 V lithium battery micro hybrid system,and 12 V multiplexing function does not cause power loss of super capacitor;(2)The SOC fluctuation of super capacitor is larger than that of lithium battery,but it can satisfy all test conditions through the strategy;(3)The voltage mutation of super capacitor is smaller than that of lithium battery.It can greatly reduce the impact of voltage on vehicle electrical appliances.The 48 V super capacitor micro hybrid system with 12 V multiplexing function is of great significance.

Rational designed isostructural MOF for the charge-discharge behavior study of super capacitors

In recent years,the rapid charge-discharge property of super capacitors based on metal-organic frameworks(MOFs)has seen excellent applications in energy storage equipment.However,the purposeful design of high-performance electrodes for MOFderived super capacitors is still an urgent problem that needs to be solved.Herein,we rationally design and prepare three MOFs with the same crystal configuration and controllable functional groups.Through the combination of rigorous experiment and calculation,we have verified the effects of the specific surface area of the electrode material as well as the binding energy between the electrode material and the electrolyte ions on the performance of the super capacitor.This work not only extends the application of MOFs,but also provides a model-material platform for the study of charge–discharge behavior of MOF-based super capacitors,creating a way of thinking for the selection and design of MOF materials for energy storage applications.

High Index SMES Device for Gravitomagnetic Field Generation

A method is described for creating a measurable unbalanced gravitational acceleration using a gravitomagnetic field surrounding a superconducting toroid as described by Forward (1962). An experimental Superconducting Magnetic Energy Storage (SMES) toroid configuration of wound superconducting nanowire is proposed to create a measurable acceleration field along the axis of symmetry, providing experimental confirmation of the additive nature of a Lense-Thirring derived gravitomagnetic field. In the present paper, gravitational coupling enhancement of this effect is explored using a high index or high permittivity material, as predicted by Sarfatti (2020) using his modification to Einstein’s General Relativity Field Equations for gravitational coupling in matter.

Preparation and characterization of Li_(4)Ti_(5)O_(12) synthesized using hydrogen titanate nanowire for hybrid super capacitor

The electrical characteristics of hybrid super capacitor were evaluated by synthesizing LTO(Li_(4)Ti_(5)O_(12))using TiO_(2) having a hydrogen titanate nanowire form.Preparation of the hydrogen titanate nanowire was implemented by using TiO_(2) having size of 60 nm and NaOH,and performing synthesis at 70℃for 6 h with a sonochemical method.LTO compound was synthesized at 150℃for 36 h and at 180℃for 36 h respectively by using the hydrogen titanate nanowire and LiOH·H2O as starting materials with a hydrothermal method.The final LTO compound was synthesized at 700℃for 6 h using a solid-state method.As a result of manufacturing the hybrid super capacitor using LTO synthesized at 180℃for 36 h with the hydrothermal method,a capacity of 198 mA·h/g has been achieved compared to a theoretical capacity of 172 mA·h/g of existing LTO,and thus,the capacity has been increased by about 13%.Further,such excellent cycle performance has ensured its possibility as a high-capacity capacitor.

Composite structure of ZnO films coated with reduced graphene oxide: structural,electrical and electrochemical properties

ZnO films coated with reduced graphene oxide（RGO-ZnO） were prepared by a simple chemical approach. The graphene oxide（GO） films transferred onto ZnO films by spin coating were reduced to RGO films by two steps（exposed to hydrazine vapor for 12 h and annealed at 600 °C）. The crystal structures, electrical and photoluminescence properties of RGO-ZnO films on quartz substrates were systematically studied. The SEM images illustrated that RGO layers have successfully been coated on the ZnO films very tightly. The PL properties of RGO-ZnO were studied. PL spectra show two sharp peaks at 390 nm and a broad visible emission around 490 nm.The resistivity of RGO-ZnO films was measured by a Hall measurement system, RGO as nanofiller considerably decrease the resistivity of ZnO films. An electrode was fabricated, using RGO-ZnO films deposited on Si substrate as active materials, for super capacitor application. By comparison of different results, we conclude that the RGOZnO composite material couples possess the properties of super capacitor.