A comparative study of two-step anodization with one-step anodization at constant voltage

2021 ◽  
Author(s):  
Huipeng Zeng ◽  
Chengyuan Li ◽  
Yuxin Dan ◽  
Yishan Lu ◽  
Weidong Sun ◽  
...  

Abstract Two-step anodization has been widely used because it can produce highly self-organized anodic TiO2 nanotubes, but the differences in morphology and current-time curve of one-step anodization and two-step anodization are rarely reported. Here, one-step anodization and two-step anodization were conducted at different voltages. By comparing the FESEM image of anodic TiO2 nanotubes fabricated by one-step anodization and two-step anodization, it was found that the variation of morphology characteristics is same with voltage. The distinction of morphology and current-time curve between one-step anodization and two-step anodization at the same voltage were analyzed: the nanotube average growth rate and porosity of two-step anodization are greater than that of one-step anodization. In the current-time curve, the duration of stage I and stage II in two-step anodization are significantly shorter than one-step anodization. The traditional field-assisted dissolution theory cannot explain the three stages of the current-time curves and their physics meaning under different voltages in the same fluoride electrolyte. Here, for the first time, the distinction between one-step anodization and two-step anodization was clarified successfully by the theories of ionic current and electronic current and oxygen bubble mould.

2022 ◽  
Author(s):  
Pengze Li ◽  
Heng Wang ◽  
Yilin Ni ◽  
Ye Song ◽  
Ming Sun ◽  
...  

The application and growth mechanism of anodic TiO2 nanotubes have been a hot topic in recent ten years, but the formation mechanism of anodic ZrO2 nanotubes is rarely studied. In...


Molecules ◽  
2020 ◽  
Vol 25 (9) ◽  
pp. 2121
Author(s):  
Vinsensia Ade Sugiawati ◽  
Florence Vacandio ◽  
Thierry Djenizian

All-solid-state batteries were fabricated by assembling a layer of self-organized TiO2 nanotubes grown on as anode, a thin-film of polymer as an electrolyte and separator, and a layer of composite LiFePO4 as a cathode. The synthesis of self-organized TiO2 NTs from Ti-6Al-4V alloy was carried out via one-step electrochemical anodization in a fluoride ethylene glycol containing electrolytes. The electrodeposition of the polymer electrolyte onto anatase TiO2 NTs was performed by cyclic voltammetry. The anodized Ti-6Al-4V alloys were characterized by scanning electron microscopy and X-ray diffraction. The electrochemical properties of the anodized Ti-6Al-4V alloys were investigated by cyclic voltammetry and chronopotentiometry techniques. The full-cell shows a high first-cycle Coulombic efficiency of 96.8% with a capacity retention of 97.4% after 50 cycles and delivers a stable discharge capacity of 63 μAh cm−2 μm−1 (119 mAh g−1) at a kinetic rate of C/10.


Coatings ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 783
Author(s):  
Ying Duan ◽  
Chen Wang ◽  
Jian Hao ◽  
Yang Jiao ◽  
Yanchao Xu ◽  
...  

In this paper, we propose for the first time the synthesis of α-MoO3 nanorods in a one-step procedure at mild temperatures. By changing the growth parameters, the microstructure and controllable morphology of the resulting products can be customized. The average diameter of the as-prepared nanorods is about 200 nm. The electrochromic and capacitance properties of the synthesized products were studied. The results show that the electrochromic properties of α-MoO3 nanorods at 550 nm have 67% high transmission contrast, good cycle stability and fast response time. The MoO3 nanorods also exhibit a stable supercapacitor performance with 98.5% capacitance retention after 10,000 cycles. Although current density varies sequentially, the nanostructure always exhibits a stable capacitor to maintain 100%. These results indicate the as-prepared MoO3 nanorods may be good candidates for applications in electrochromic devices and supercapacitors.


Materials ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 510
Author(s):  
Wangzhu Cao ◽  
Kunfeng Chen ◽  
Dongfeng Xue

Nanoscale engineering of regular structured materials is immensely demanded in various scientific areas. In this work, vertically oriented TiO2 nanotube arrays were grown by self-organizing electrochemical anodization. The effects of different fluoride ion concentrations (0.2 and 0.5 wt% NH4F) and different anodization times (2, 5, 10 and 20 h) on the morphology of nanotubes were systematically studied in an organic electrolyte (glycol). The growth mechanisms of amorphous and anatase TiO2 nanotubes were also studied. Under optimized conditions, we obtained TiO2 nanotubes with tube diameters of 70–160 nm and tube lengths of 6.5–45 μm. Serving as free-standing and binder-free electrodes, the kinetic, capacity, and stability performances of TiO2 nanotubes were tested as lithium-ion battery anodes. This work provides a facile strategy for constructing self-organized materials with optimized functionalities for applications.


2021 ◽  
Vol 12 (5) ◽  
pp. 645-649
Author(s):  
Yu Gu ◽  
Yuqing Qiao ◽  
Yusen Meng ◽  
Ming Yu ◽  
Bowu Zhang ◽  
...  

Herein, we report for the first time the synthesis of polypyrrole copolymers with good solvent-dispersibility under gamma-ray irradiation at room temperature in air.


The Analyst ◽  
2021 ◽  
Author(s):  
Lisha Mei ◽  
Wentang Zhao ◽  
Yiju Song ◽  
Li Zhang ◽  
Mengmeng Zhang ◽  
...  

In this study, we used inexpensive and synthetic simple electrocatalysts replacement conventional precious metal materials to reduce hydrogen peroxide (H2O2). We first time developed N-doped graphene-coated CuFe@MoC using one-step calcination...


RSC Advances ◽  
2017 ◽  
Vol 7 (53) ◽  
pp. 33526-33531 ◽  
Author(s):  
Shaoyu Zhang ◽  
Mengshi Yu ◽  
Liming Xu ◽  
Siwei Zhao ◽  
Jianfei Che ◽  
...  

Multilayer anodic TiO2 nanotubes with A-shaped sidewalls are first fabricated in HBF4-containing electrolyte by a one-step galvanostatic anodization.


RSC Advances ◽  
2015 ◽  
Vol 5 (48) ◽  
pp. 38527-38532 ◽  
Author(s):  
Di Guo ◽  
Hongxu Guo ◽  
Yingchang Ke ◽  
Dongfang Wang ◽  
Jianhua Chen ◽  
...  

A facile one-step mechanochemical process from CuCl2·2H2O and thiourea to fabricate novel [Cu(tu)]Cl·1/2H2O nanobelts has been observed for the first time, and the nanobelts were used as an electrode material for a supercapacitor.


2011 ◽  
Vol 8 (1) ◽  
pp. 29-34
Author(s):  
Baghdad Science Journal

This study was for searching for Cholera Bacteria serotype which causes epidemiology Cholera in the 2007 in a fast method which contains (Rapid Visual Test) (Crystal V.C.) which was used for the first time in Iraq to diagnosis of Cholera Bacteria & compared with the traditional bacteriology method. The Cholera disease is one of the most dangerous epidemiological diseases which lead to death with a percentage of (50 – 70) % in the severe cases for untreated patients . For this purpose, 100 samples of stool from the patients from a (13) hospitals in Baghdad Governorate in the period from August to the end of December. The Cholera was diagnosis in two methods, 1st method was the fast method using the nitrocellulose which is coated with anti-body of Cholera Bacteria .The results was compared with the 2nd method which depends on the cultural characteristics of the cultural media, also the bacteria was diagnosis using the biochemical inspects by the system of API 20E in addition to the using of antisera to specify serotype& sub-serotype ( Monovalent, Polyvalent(O1) . Also, the relation between the disease & the months in the year in which the disease appear was studied. The results show the ability to isolate & identifecate (78) isolate for the serotype (01) in the fast method ( Rapid Visual Test ) ( Crystal V-C ) , & after the bacteriology inspects on these (78) isolate the all isolates were belongs for Cholera Bacteria of the serotype (01) till the sub-serotype , all the (78) isolates were belongs to the sub-serotype (Inaba). The results show, the most infection was in September (36) , & October (22).


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