Water Adsorption, Solvation, and Deliquescence of Potassium Bromide Thin Films on SiO2 Studied by Ambient-Pressure X-ray Photoelectron Spectroscopy

2010 ◽  
Vol 114 (35) ◽  
pp. 14900-14906 ◽  
Author(s):  
Kenta Arima ◽  
Peng Jiang ◽  
Xingyi Deng ◽  
Hendrik Bluhm ◽  
Miquel Salmeron
2011 ◽  
Vol 295-297 ◽  
pp. 1958-1963
Author(s):  
Jing Zhi Yang ◽  
Li Juan Fu ◽  
Xiao Peng Qi ◽  
Hong Yun Li

Zn1-xCoxO thin films on sapphire (0001) substrates were synthesized by laser molecular beam epitaxy (LMBE) method at various temperatures under a work ambient pressure of 5.0 x 10-5Pa condition. X-ray diffraction (XRD) spectra, UV–visible transmission spectra and X-ray photoelectron spectroscopy (XPS), photoluminescence (PL) spectra were employed to characterize the properties of samples. All samples were of wurtzite hexagonal structure with the preferential c-axis-orientation. Co2+ions incorporated into ZnO lattice and substituted for Zn2+ions. ZnLMM Auger spectrum implied Zn interstitials existed in sample. The optical transmission of all samples was relatively high in visible region. Two PL emission peaks located at 418 nm and 490 nm were assigned to the electron transition from the Zn interstitials to the top of the valence band and from the Zn interstitials to the Zn vacancies, respectively.


2021 ◽  
Vol 118 (49) ◽  
pp. e2108325118
Author(s):  
Wahid Zaman ◽  
Ray A. Matsumoto ◽  
Matthew W. Thompson ◽  
Yu-Hsuan Liu ◽  
Yousuf Bootwala ◽  
...  

A continuum of water populations can exist in nanoscale layered materials, which impacts transport phenomena relevant for separation, adsorption, and charge storage processes. Quantification and direct interrogation of water structure and organization are important in order to design materials with molecular-level control for emerging energy and water applications. Through combining molecular simulations with ambient-pressure X-ray photoelectron spectroscopy, X-ray diffraction, and diffuse reflectance infrared Fourier transform spectroscopy, we directly probe hydration mechanisms at confined and nonconfined regions in nanolayered transition-metal carbide materials. Hydrophobic (K+) cations decrease water mobility within the confined interlayer and accelerate water removal at nonconfined surfaces. Hydrophilic cations (Li+) increase water mobility within the confined interlayer and decrease water-removal rates at nonconfined surfaces. Solutes, rather than the surface terminating groups, are shown to be more impactful on the kinetics of water adsorption and desorption. Calculations from grand canonical molecular dynamics demonstrate that hydrophilic cations (Li+) actively aid in water adsorption at MXene interfaces. In contrast, hydrophobic cations (K+) weakly interact with water, leading to higher degrees of water ordering (orientation) and faster removal at elevated temperatures.


Author(s):  
Pei-Shun Lin ◽  
Sun-Tang Chang ◽  
Sheng-Yuan Chen ◽  
Dah-An Luh ◽  
Chia-Hsin Wang ◽  
...  

2018 ◽  
Vol 10 (43) ◽  
pp. 37661-37670 ◽  
Author(s):  
Angelique Jarry ◽  
Sandrine Ricote ◽  
Aaron Geller ◽  
Christopher Pellegrinelli ◽  
Xiaohang Zhang ◽  
...  

2019 ◽  
Vol 21 (9) ◽  
pp. 4920-4930 ◽  
Author(s):  
Neus Domingo ◽  
Elzbieta Pach ◽  
Kumara Cordero-Edwards ◽  
Virginia Pérez-Dieste ◽  
Carlos Escudero ◽  
...  

Unveiling surface adsorbates under atmospheric conditions and in surface water redox reactions on TiO2 terminated surfaces and ferroelectric oxides, as studied by AP-XPS.


2009 ◽  
Vol 24 (8) ◽  
pp. 2520-2527 ◽  
Author(s):  
Yonghao Lu ◽  
Junping Wang ◽  
Yaogen Shen ◽  
Dongbai Sun

A series of Ti-B-C-N thin films were deposited on Si (100) at 500 °C by incorporation of different amounts of N into Ti-B-C using reactive unbalanced dc magnetron sputtering in an Ar-N2 gas mixture. The effect of N content on phase configuration, nanostructure evolution, and mechanical behaviors was studied by x-ray diffraction, x-ray photoelectron spectroscopy, Raman spectroscopy, high-resolution transmission electron microscopy, and microindentation. It was found that the pure Ti-B-C was two-phased quasi-amorphous thin films comprising TiCx and TiB2. Incorporation of a small amount of N not only dissolved into TiCx but also promoted growth of TiCx nano-grains. As a result, nanocomposite thin films of nanocrystalline (nc-) TiCx(Ny) (x + y < 1) embedded into amorphous (a-) TiB2 were observed until nitrogen fully filled all carbon vacancy lattice (at that time x + y = 1). Additional increase of N content promoted formation of a-BN at the cost of TiB2, which produced nanocomposite thin films of nc-Ti(Cx,N1-x) embedded into a-(TiB2, BN). Formation of BN also decreased nanocrystalline size. Both microhardness and elastic modulus values were increased with an increase of N content and got their maximums at nanocomposite thin films consisting of nc-Ti(Cx,N1-x) and a-TiB2. Both values were decreased after formation of BN. Residual compressive stress value was successively decreased with an increase of N content. Enhancement of hardness was attributed to formation of nanocomposite structure and solid solution hardening.


Sign in / Sign up

Export Citation Format

Share Document