Metal aluminum (A1) thin films are prepared by 2450 MHz electron cyclotron resonance plasma-assisted atomic layer deposition on glass and p-Si substrates using trimethylaluminum as the precursor and hydrogen as the ...Metal aluminum (A1) thin films are prepared by 2450 MHz electron cyclotron resonance plasma-assisted atomic layer deposition on glass and p-Si substrates using trimethylaluminum as the precursor and hydrogen as the reductive gas. We focus our attention on the plasma source for the thin-film preparation and annealing of the as-deposited films relative to the surface square resistivity. The square resistivity of as-deposited A1 films is greatly reduced after annealing and almost reaches the value of bulk metal. Through chemical and structural analysis, we conclude that the square resistivity is determined by neither the contaminant concentration nor the surface morphology, but by both the crystallinity and crystal size in this process.展开更多
Soda-lime glasses were treated by electric field-assisted diffusion(EFAD) process. The mechanical properties and structural evolution on both glass anode and cathode surfaces were investigated, respectively. It was ...Soda-lime glasses were treated by electric field-assisted diffusion(EFAD) process. The mechanical properties and structural evolution on both glass anode and cathode surfaces were investigated, respectively. It was found that the EFAD resulted in the formation of a Na depletion layer on anode surface, which caused the relaxation of the glass anode surface network and the formation of a number of defects. Correspondingly, the hardness and flexural strength declined in anode surface compared to that of the original glass. On the other hand, the EFAD also created a compressive layer on cathode surface, causing the improvement of the hardness and flexural strength on cathode surface. The defected structure could be reconstructed by additional annealing process.展开更多
Inorganic buffer layers such as SiO2 or TiO2 and transparent conductive indium-tin-oxide (ITO) films were prepared on polyethylene terephthalate (PET) substrates by ion assisted deposition (IAD) at room temperat...Inorganic buffer layers such as SiO2 or TiO2 and transparent conductive indium-tin-oxide (ITO) films were prepared on polyethylene terephthalate (PET) substrates by ion assisted deposition (IAD) at room temperature, and the effects of SiO2 and TiOzon the bending resistance performance of flexible ITO films were investigated. The results show that ITO films with SiO2 or TiO2 buffer layer have better resistance stabilities compared to ones without the buffer layer when the ITO films are inwards bent at a bending radius more than 1.2 cm and when the ITO films are outwards bent at a bending radius from 0.8 cm to 1.2 cm. 1TO films with SiO2 buffer layer have better resistance sta- bilities compared to ones with TiO2 buffer layer after the ITO fdms are bent several hundreds of cycles at the same bending radius, for the adhesion of SiO2 is stronger than that of TiO2. The compressive stress resulted from inward bending leads to the formation of more defects in the ITO films compared with the tensile stress arising from outward bending. SiO2 and TiO2 buffer layers can effectively improve the crystallinity of ITO films in (400), (440) directions.展开更多
Two-dimensional(2D) materials have attracted considerable attention because of their novel and tunable electronic,optical, ferromagnetic, and chemical properties. Compared to mechanical exfoliation and chemical vapor ...Two-dimensional(2D) materials have attracted considerable attention because of their novel and tunable electronic,optical, ferromagnetic, and chemical properties. Compared to mechanical exfoliation and chemical vapor deposition, polymer-assisted deposition(PAD) is more suitable for mass production of 2D materials owing to its good reproducibility and reliability. In this review, we summarize the recent development of PAD on syntheses of 2D materials. First, we introduce principles and processing steps of PAD. Second, 2D materials, including graphene, MoS2, and MoS2/glassy-graphene heterostructures, are presented to illustrate the power of PAD and provide readers with the opportunity to assess the method. Last, we discuss the future prospects and challenges in this research field. This review provides a novel technique for preparing 2D layered materials and may inspire new applications of 2D layered materials.展开更多
A novel sample preparation method of matrix-assisted laser desorption/ionization mass spectrometry for polystyrene was reported. Compared to the conventional dried-droplet method, the efficiency of ionization and sign...A novel sample preparation method of matrix-assisted laser desorption/ionization mass spectrometry for polystyrene was reported. Compared to the conventional dried-droplet method, the efficiency of ionization and signal intensity of mass spectra were improved. The mechanism was also analyzed.展开更多
Low temperature catalysts are attracting increasing attention in the selective catalytic reduction(SCR)of NO with NH3.Mn Ox-decorated Mg Al layered double oxide(Mn/Mg Al-LDO)was synthesized via a facile fast pour assi...Low temperature catalysts are attracting increasing attention in the selective catalytic reduction(SCR)of NO with NH3.Mn Ox-decorated Mg Al layered double oxide(Mn/Mg Al-LDO)was synthesized via a facile fast pour assisted co-precipitation(FP-CP)process.Compared to the Mn/Mg Al-LDO obtained via slow drop assisted coprecipitation(SD-CP)method,the Mn/Mg Al-LDO(FP-CP)has excellent activity.The Mn/Mg Al-LDO(FP-CP)catalyst was shown to possess a high NO conversion rate of 76%-100%from 25 to 150℃,which is much better than the control Mn/Mg Al-LDO(SD-CP)(29.4%-75.8%).In addition,the Mn/Mg Al-LDO(FP-CP)offered an enhanced NO conversion rate of 97%and a N2selectivity of 97.3%at 100℃;the NO conversion rate was 100%and the N2selectivity was 90%at 150℃with a GHSV of 60,000 h^-1.The Mn/Mg Al-LDO(FP-CP)catalyst exhibited a smaller fragment nano-sheet structure(sheet thickness of 7.23 nm).An apparent lattice disorder was observed in the HRTEM image confirming the presence of many defects.The H2-TPR curves show that the Mn/Mg Al-LDO(FP-CP)catalyst has abundant reducing substances.Furthermore,the enhanced surface acidity makes the NH3concentration of the Mn/Mg Al-LDO(FP-CP)catalyst lower than 100 ml·m^-3after the reaction from 25 to 400℃.This can effectively reduce the ammonia escape rate in the SCR reaction.Thus,the Mn/Mg Al-LDO(FP-CP)catalyst has potential applications in stationary industrial installations for environmentally friendly ultra-low temperature SCR.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant No. 11175024)the Beijing Natural Science Foundation, China (Grant No. 1112012)+1 种基金the Science and Technology on Surface Engineering Laboratorythe Beijing Education Committee, China (Grant Nos. BM201002, 2011BAD24B01, KM201110015008, KM201010015005, and PHR20110516)
文摘Metal aluminum (A1) thin films are prepared by 2450 MHz electron cyclotron resonance plasma-assisted atomic layer deposition on glass and p-Si substrates using trimethylaluminum as the precursor and hydrogen as the reductive gas. We focus our attention on the plasma source for the thin-film preparation and annealing of the as-deposited films relative to the surface square resistivity. The square resistivity of as-deposited A1 films is greatly reduced after annealing and almost reaches the value of bulk metal. Through chemical and structural analysis, we conclude that the square resistivity is determined by neither the contaminant concentration nor the surface morphology, but by both the crystallinity and crystal size in this process.
基金Funded by Shanghai Science and Technology Committee(No.12nm0504700)
文摘Soda-lime glasses were treated by electric field-assisted diffusion(EFAD) process. The mechanical properties and structural evolution on both glass anode and cathode surfaces were investigated, respectively. It was found that the EFAD resulted in the formation of a Na depletion layer on anode surface, which caused the relaxation of the glass anode surface network and the formation of a number of defects. Correspondingly, the hardness and flexural strength declined in anode surface compared to that of the original glass. On the other hand, the EFAD also created a compressive layer on cathode surface, causing the improvement of the hardness and flexural strength on cathode surface. The defected structure could be reconstructed by additional annealing process.
基金supported by the National Eleventh Five-Year Pre-research Project of China (No.51302060203)
文摘Inorganic buffer layers such as SiO2 or TiO2 and transparent conductive indium-tin-oxide (ITO) films were prepared on polyethylene terephthalate (PET) substrates by ion assisted deposition (IAD) at room temperature, and the effects of SiO2 and TiOzon the bending resistance performance of flexible ITO films were investigated. The results show that ITO films with SiO2 or TiO2 buffer layer have better resistance stabilities compared to ones without the buffer layer when the ITO films are inwards bent at a bending radius more than 1.2 cm and when the ITO films are outwards bent at a bending radius from 0.8 cm to 1.2 cm. 1TO films with SiO2 buffer layer have better resistance sta- bilities compared to ones with TiO2 buffer layer after the ITO fdms are bent several hundreds of cycles at the same bending radius, for the adhesion of SiO2 is stronger than that of TiO2. The compressive stress resulted from inward bending leads to the formation of more defects in the ITO films compared with the tensile stress arising from outward bending. SiO2 and TiO2 buffer layers can effectively improve the crystallinity of ITO films in (400), (440) directions.
基金support from the National Natural Science Foundation of China (Grant No.11774279)National Natural Science Foundation of China (Nos. 51602173 and 11774191)+3 种基金the Young Talent Support Plan of Xi’an Jiaotong Universitythe Instrument Analysis Center of Xi’an Jiaotong Universitythe support from National Key R&D Program of China (No. 2018YFA0208400)Fok Ying-Tong Education Foundation (No. 161042)
文摘Two-dimensional(2D) materials have attracted considerable attention because of their novel and tunable electronic,optical, ferromagnetic, and chemical properties. Compared to mechanical exfoliation and chemical vapor deposition, polymer-assisted deposition(PAD) is more suitable for mass production of 2D materials owing to its good reproducibility and reliability. In this review, we summarize the recent development of PAD on syntheses of 2D materials. First, we introduce principles and processing steps of PAD. Second, 2D materials, including graphene, MoS2, and MoS2/glassy-graphene heterostructures, are presented to illustrate the power of PAD and provide readers with the opportunity to assess the method. Last, we discuss the future prospects and challenges in this research field. This review provides a novel technique for preparing 2D layered materials and may inspire new applications of 2D layered materials.
文摘A novel sample preparation method of matrix-assisted laser desorption/ionization mass spectrometry for polystyrene was reported. Compared to the conventional dried-droplet method, the efficiency of ionization and signal intensity of mass spectra were improved. The mechanism was also analyzed.
基金supported by Science and Technology Innovation Talents Program of Bingtuan(No.2019CB025)Major Scientific and Technological Project of Bingtuan(No.2018AA002)。
文摘Low temperature catalysts are attracting increasing attention in the selective catalytic reduction(SCR)of NO with NH3.Mn Ox-decorated Mg Al layered double oxide(Mn/Mg Al-LDO)was synthesized via a facile fast pour assisted co-precipitation(FP-CP)process.Compared to the Mn/Mg Al-LDO obtained via slow drop assisted coprecipitation(SD-CP)method,the Mn/Mg Al-LDO(FP-CP)has excellent activity.The Mn/Mg Al-LDO(FP-CP)catalyst was shown to possess a high NO conversion rate of 76%-100%from 25 to 150℃,which is much better than the control Mn/Mg Al-LDO(SD-CP)(29.4%-75.8%).In addition,the Mn/Mg Al-LDO(FP-CP)offered an enhanced NO conversion rate of 97%and a N2selectivity of 97.3%at 100℃;the NO conversion rate was 100%and the N2selectivity was 90%at 150℃with a GHSV of 60,000 h^-1.The Mn/Mg Al-LDO(FP-CP)catalyst exhibited a smaller fragment nano-sheet structure(sheet thickness of 7.23 nm).An apparent lattice disorder was observed in the HRTEM image confirming the presence of many defects.The H2-TPR curves show that the Mn/Mg Al-LDO(FP-CP)catalyst has abundant reducing substances.Furthermore,the enhanced surface acidity makes the NH3concentration of the Mn/Mg Al-LDO(FP-CP)catalyst lower than 100 ml·m^-3after the reaction from 25 to 400℃.This can effectively reduce the ammonia escape rate in the SCR reaction.Thus,the Mn/Mg Al-LDO(FP-CP)catalyst has potential applications in stationary industrial installations for environmentally friendly ultra-low temperature SCR.