A mass of oxygen vacancies are successfully introduced into TiO2 nanotube arrays using low-cost NaBH4 as a reductant in a liquid-phase environment. By controlling and adjusting the reduction time over the range of 0-24 h, the doping concentration of the oxygen vacancy is controllable and eventually reaches saturation. Meanwhile, the thermal stability of oxygen vacancies is also investigated, indicating that part of the oxygen vacancies remain stable up to 250 °C. In addition, this liquid-phase reduction strategy significantly lowers the requirements of instruments and cost. More interesting, reduced TiO2 nanotube arrays show drastically enhanced field emission performances including substantially decreased turn-on field from 25.01 to 2.65 V/μm, a high current density of 3.5 mA/cm(2) at 7.2 V/μm, and an excellent field emission stability and repeatability. These results are attributed to the oxygen vacancies obtained by reducing in NaBH4 solution, resulting in a reduced effective work function and an increased conductivity.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/am503379y | DOI Listing |
ACS Appl Nano Mater
January 2024
Department of Chemistry, University of Central Florida, Orlando, Florida 32816 (USA).
Understanding the origin of enhanced catalytic activity is critical to heterogeneous catalyst design. This is especially important for non-noble metal-based catalysts, notably metal oxides, which have recently emerged as viable alternatives for numerous thermal catalytic processes. For thermal catalytic reduction/hydrogenation using metal oxide nanoparticles, enhanced catalytic performance is typically attributed to increased surface area and oxygen vacancies.
View Article and Find Full Text PDFSci Rep
December 2024
Graduate School of Engineering, University of Hyogo, Himeji, 671-2280, Japan.
The effect of hot isostatic pressing (HIP) on the thermoelectric power factor of zinc oxide (ZnO) has been examined. ZnO is expected to be a potential n-type oxide thermoelectric material that could enhance the thermoelectric conversion efficiency. The HIP treatment is useful for densifying the material and controlling crystal defects in the material by applying high temperatures and pressures simultaneously.
View Article and Find Full Text PDFJ Colloid Interface Sci
December 2024
Department of Environmental Science and Engineering, College of Environment and Resources, Xiangtan University, Xiangtan 411105, China.
Ferrous oxalate (FeCO)-based composite has been recognized as an eminent catalyst for Cr(III)-ethylenediamine tetraacetic acid (Cr(III)-EDTA) decomplexation. However, their practical application has been limited by low cycling capacity and an ambiguous mechanism. In this research, a composite catalyst consisting of biotite loaded with nano FeCO (CFS90) was prepared directly from iron-containing silicate tailing.
View Article and Find Full Text PDFAdv Sci (Weinh)
December 2024
New Cornerstone Science Laboratory, MOE Key Laboratory for Analytical Science of Food Safety and Biology, College of Chemistry, Fuzhou University, Fuzhou, 350108, China.
Radiodynamic therapy that employs X-rays to trigger localized reactive oxygen species (ROS) generation can tackle the tissue penetration issue of phototherapy. Although calcium tungstate (CaWO) shows great potential as a radiodynamic agent benefiting from its strong X-ray absorption and the ability to generate electron-hole (e-h) pairs, slow charge carrier transfer and fast e-h recombination greatly limit its ROS-generating performance. Herein, via a one-pot wet-chemical method, oxygen vacancy-rich amorphous/crystalline heterophase CaWO nanoparticles (Ov-a/c-CaWO NPs) with enhanced radiodynamic effect are synthesized for radiodynamic-immunotherapy of cancer.
View Article and Find Full Text PDFSci Rep
December 2024
Shandong Engineering Research Center of Green and High-value Marine Fine Chemical, Weifang University of Science and Technology, Shouguang, 262700, People's Republic of China.
To enhance the volumetric energy density and initial coulombic efficiency (ICE) of titanium oxide (TiO) as anode electrode material for lithium-ion batteries (LIB), this study employed a surface-confined in-situ inter-growth mechanism to prepare a TiO embedded carbon microsphere composite. The results revealed that the composite exhibited a highly integrated structure of TiO with oxygen vacancies and carbon, along with an exceptionally small specific surface area of 11.52 m/g.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!