Nature Communications
·
2018
·Vol. 9
·期 1
·1-9
·
IF 12.353
Ou Gang,Xu Yushuai,Wen Bo,Lin Rui,Ge Binghui,Tang Yan,Liang Yuwei,Yang Cheng,Huang Kai,Zu Di,Yu Rong,Chen Wenxing,Li Jun,Wu Hui,Liu Li-Min,Li Yadong
Defects can greatly influence the properties of oxide materials; however, facile defect engineering of oxides at room temperature remains challenging. The generation of defects in oxides is difficult to control by conventional chemical reduction methods that usually require high temperatures and are time consuming. Here, we develop a facile room-temperature lithium reduction strategy to implant defects into a series of oxide nanoparticles including titanium dioxide (TiO 2 ), zinc oxide (ZnO), tin dioxide (SnO 2 ), and cerium dioxide (CeO 2 ). Our lithium reduction strategy shows advantages including all-room-temperature processing, controllability, time efficiency, versatility and scalability. As a potential application, the photocatalytic hydrogen evolution performance of defective TiO 2 is examined. The hydrogen evolution rate increases up to 41.8 mmol g −1 h −1 under one solar light irradiation, which is ~3 times higher than that of the pristine nanoparticles. The strategy of tuning defect oxides used in this work may be beneficial for many other related applications.
研究领域:
材料科学
·
化学工程
·
能源科学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2021
·Vol. 168
·期 10
·102505
·
IF 4.316
Chenteng Sun,Qian Xu,Yongxiang Yang,Xingli Zou,Hongwei Cheng,Xionggang Lu
The electrochemical behaviors of Li+ and Nd3+ were investigated on W, liquid Sn pool and Sn film electrodes in LiCl-KCl-NdCl3 melt at 673 K. Various electrochemical techniques, such as cyclic voltammogram, square wave voltammogram, and open circuit chronopotentiometry, were conducted to evaluate the electrochemical behaviors of Li+ and Nd3+. The reduction of Nd3+ was found to be a two-step process in the W electrode and a one-step process in the liquid Sn electrode. During the formation of the Nd-Sn intermetallic compounds, only the NdSn3 would be formed without the reduction of the Li+ in the liquid Sn electrode. When the reduction potential moves over −2.77 V vs Cl2/Cl−, the Li+ in the electrolyte would inevitable be reduced into the liquid Sn electrode. The Nd-Sn intermetallic compounds were deposited on the liquid Sn pool electrode at −2.74 V vs Cl2/Cl− in the LiCl-KCl-NdCl3 melts for 5 h. The products were characterized by SEM-EDS and XRD. The loose product on the surface of the deposition displayed the existence of NdSn3 in Nd-Sn intermetallic compounds. The high content of Nd inclusion formed by segregation was detected in the solidified Sn electrode.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Qing Sun,Ziyang Guo,Tie Shu,Yongfei Li,Kailin Li,Yuxin Zhang,Liang Li,Jiaoyi Ning,Ke Xin Yao
The traditional methods for creating oxygen vacancies in materials present several challenges and limitations, such as high preparation temperatures, limited oxygen vacancy generation, and morphological destruction, which hinder the application of transition metal oxides in the field of zinc–air batteries (ZABs). In order to address these limitations, we have introduced a pioneering lithium reduction strategy for generating oxygen vacancies in δ-MnO2@MXene composite materials. This strategy stands out for its simplicity of implementation, applicability at room temperature, and preservation of the material’s structural integrity. This research demonstrates that aqueous Ov-MnO2@MXene-5, with introduced oxygen vacancies, exhibits an outstanding oxygen reduction reaction (ORR) activity with an ORR half-wave potential reaching 0.787 V. DFT calculations have demonstrated that the enhanced activity could be attributed to adjustments in the electronic structure and alterations in adsorption bond lengths. These adjustments result from the introduction of oxygen vacancies, which in turn promote electron transport and catalytic activity. In the context of zinc–air batteries, cells with Ov-MnO2@MXene-5 as the air cathode exhibit outstanding performance, featuring a significantly improved maximum power density (198.3 mW cm–2) and long-term cycling stability. Through the innovative strategy of introducing oxygen vacancies, this study has successfully enhanced the electrochemical catalytic performance of MnO2, overcoming the limitations associated with traditional methods for creating oxygen vacancies. Consequently, this research opens up new avenues and directions for nonprecious metal catalyst application in ZABs.
研究领域:
材料科学
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电化学
·
能源存储与转换
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2019
·
IF 8.456
Gang Ou,Fengchi Wu,Kai Huang,Naveed Hussain,Di Zu,Hehe Wei,Binghui Ge,Huizhen Yao,Lai Liu,Henan Li,Yumeng Shi,Hui Wu
Spinel oxides have attracted widespread interest for electrocatalytic applications owing to their unique crystal structure and properties. The surface structure of spinel oxides significantly influences the electrocatalytic performance of spinel oxides. Herein, we report a Li reduction strategy that can quickly tune the surface structure of CoFe2O4 (CFO) nanoparticles and optimize its electrocatalytic oxygen evolution reaction (OER) performance. Results show that a large number of defective domains have been successfully introduced at the surface of CFO nanopowders after Li reduction treatment. The defective CFO nanoparticles demonstrate significantly improved electrocatalytic OER activity. The OER potential observed a negative shift from 1.605 to 1.513 V at 10 mA cm–2, whereas the Tafel slope is greatly decreased to 42.1 mV dec–1 after 4 wt % Li reduction treatment. This efficient Li reduction strategy can also be applied to engineer the surface defect structure of other material systems and broaden their applications.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
PubMed
高影响因子
Chemistry-An Asian Journal
·
2019
·Vol. 14
·期 16
·2796-2801
·
IF 3.698
Fengchi Wu,Gang Ou,Ye Wang,Haizhe Zhong,Lifu Zhang,Henan Li,Yumeng Shi
Urea is an important organic pollutants in sewage and needs to be removed for environmental protection. Here, we report defective NiFe 2 O 4 (NFO) nanoparticles with excellent performance for urea electro-oxidation. The results show that defects can be effectively implanted at the surface of NFO nanoparticles by a facile and versatile lithium reduction method without affecting its main crystal structure and grain size. The defective NFO-5Li nanoparticles displayed a significantly improved urea electro-oxidation performance compared with NFO-Pristine nanoparticles. Particularly, the NFO-Pristine and NFO-5Li show a potential of 1.398 and 1.361 V at the current density of 10 mA cm −2 and Tafel slope of 37.3 and 31.4 mV dec −1 , respectively. In addition, the NFO-5Li nanoparticles also revealed outstanding electrocatalytic stability. The superior performance can be attributed to the designed tunable surface defect engineering. Furthermore, the defect engineering strategy as well as the defective NFO nanoparticles hold great potential for applications in other materials and areas.
研究领域:
环境科学
·
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）