Barium titanate（BTO） thin films were deposited on polycrystalline Ni foils by using the polymer assisted deposition（PAD） technique.The growth conditions including ambient and annealing temperatures were carefully ...Barium titanate（BTO） thin films were deposited on polycrystalline Ni foils by using the polymer assisted deposition（PAD） technique.The growth conditions including ambient and annealing temperatures were carefully optimized based on thermal dynamic analysis to control the oxidation processing and interdiffusion.Crystal structures,surface morphologies,and dielectric performance were examined and compared for BTO thin films annealed under different temperatures.Correlations between the fabrication conditions,microstructures,and dielectric properties were discussed.BTO thin films fabricated under the optimized conditions show good crystalline structure and promising dielectric properties with εr～ 400 and tan δ 〈 0.025 at 100 kHz.The data demonstrate that BTO films grown on polycrystalline Ni substrates by PAD are promising in device applications.展开更多
分别用聚合物辅助沉积法和金属有机物分解法制备了WO_3和BiVO_4半导体薄膜电极。利用固体紫外-可见漫反射光谱、电化学阻抗和线性扫描伏安法,对WO_3和BiVO_4半导体薄膜电极的能带结构进行了表征。制备了WO_3/BiVO_4异质结复合光电极,并...分别用聚合物辅助沉积法和金属有机物分解法制备了WO_3和BiVO_4半导体薄膜电极。利用固体紫外-可见漫反射光谱、电化学阻抗和线性扫描伏安法,对WO_3和BiVO_4半导体薄膜电极的能带结构进行了表征。制备了WO_3/BiVO_4异质结复合光电极,并通过扫描电子显微镜、X射线衍射和X射线光电子能谱,对该复合光电极的断面形貌、晶型结构和物质组成进行了分析。最后,对WO_3/BiVO_4复合光电极的光电转化性能进行了研究。研究结果表明:均为单斜晶型的WO_3和BiVO_4之间形成了膜厚约为450 nm的II型异质结;在施加相对于可逆氢电极1.23 V的电势时,WO_3/BiVO_4光电极的光电流密度可以达到1.926 m A/cm^2,表现出了良好的光电转化性能。展开更多
We studied the role of oxygen in Pr2 CuO_(4±δ) thin films fabricated by the polymer assisted deposition method. The magnetoresistance and Hall resistivity of Pr2 CuO_(4±δ) samples were systematically inves...We studied the role of oxygen in Pr2 CuO_(4±δ) thin films fabricated by the polymer assisted deposition method. The magnetoresistance and Hall resistivity of Pr2 CuO_(4±δ) samples were systematically investigated. It was found that with decreasing oxygen content, the low-temperature Hall coefficient(RH) and magnetoresistance changed from negative to positive, similar to those with the increase of Ce-doped concentration in R_(2-x)Ce_x CuO_4 (R = La, Nd, Pr, Sm, Eu). In addition, we observed that the dependence of the superconducting critical temperature Tc with RH for the Pr_(2-x) Ce_x CuO_4 perfectly overlapped with that of Pr_2 CuO_(4±δ) . These findings point to the fact that the doped electrons induced by the oxygen removal are responsible for the superconductivity of the T-phase parent compounds.展开更多
To increase the critical thickness of CeO2 single buffer layer, the polymer assisted chemical solution deposition (PACSD) approach has been adopted to prepare a single buffer layer of Gd0.3Ce0.7O1.85-x (GCO) on bi-axi...To increase the critical thickness of CeO2 single buffer layer, the polymer assisted chemical solution deposition (PACSD) approach has been adopted to prepare a single buffer layer of Gd0.3Ce0.7O1.85-x (GCO) on bi-axially textured Ni-5%W alloy substrate, and the influences of different annealing temperatures on texture and microstructure of the buffer layer has also been studied in this paper. The results demonstrate that a well textured, dense and smooth GCO single buffer layer with thickness of 180 nm has been obtained at 1100 ℃ annealing treatment. GdBa2Cu3O7-y (GBCO) film has been deposited on GCO buffered substrate via the similar approach, which is also well textured, dense and smooth. All these show that preparation of GCO buffer layer by PACSD method is an effective approach to prepare single buffer layer for large scale production.展开更多
Polymer-assisted deposition technique has been used to deposit Al2O3 and N-doped Al2O3 （AION） thin films on Si（100） substrates. The chemical compositions, crystallinity, and thermal conductivity of the as-grown fi...Polymer-assisted deposition technique has been used to deposit Al2O3 and N-doped Al2O3 （AION） thin films on Si（100） substrates. The chemical compositions, crystallinity, and thermal conductivity of the as-grown films have been characterized by X-ray photoelectron spectroscopy （XPS）, X-ray diffraction （XRD）, and 3-omega method, respectively. Amorphous and polycrystalline Al2O3 and AlON thin films have been formed at 700 ℃ and 1000 ℃. The thermal conductivity results indicated that the effect of nitrogen doping on the thermal conductivity is determined by the competition of the increase of Al-N bonding and the suppression of crystallinity. A 67% enhancement in thermal conductivity has been achieved for the samples grown at 700 ℃, demonstrating that the nitrogen doping is an effective way to improve the thermal performance of polymer-assisted-deposited Al2O3 thin films at a relatively low growth temperature.展开更多
Three-dimensional-structured metal oxides have myriad applications for optoelectronic devices.Comparing to conventional lithography-based manufacturing methods which face significant challenges for 3D device architect...Three-dimensional-structured metal oxides have myriad applications for optoelectronic devices.Comparing to conventional lithography-based manufacturing methods which face significant challenges for 3D device architectures,additive manufacturing approaches such as direct ink writing offer convenient,on-demand manufacturing of 3D oxides with high resolutions down to sub-micrometer scales.However,the lack of a universal ink design strategy greatly limits the choices of printable oxides.Here,a universal,facile synthetic strategy is developed for direct ink writable polymer precursor inks based on metal-polymer coordination effect.Specifically,polyethyleneimine functionalized by ethylenediaminetetraacetic acid is employed as the polymer matrix for adsorbing targeted metal ions.Next,glucose is introduced as a crosslinker for endowing the polymer precursor inks with a thermosetting property required for 3D printing via the Maillard reaction.For demonstrations,binary(i.e.,ZnO,CuO,In_(2)O_(3),Ga_(2)O_(3),TiO_(2),and Y_(2)O_(3)) and ternary metal oxides(i.e.,BaTiO_(3) and SrTiO_(3)) are printed into 3D architectures with sub-micrometer resolution by extruding the inks through ultrafine nozzles.Upon thermal crosslinking and pyrolysis,the 3D microarchitectures with woodpile geometries exhibit strong light-matter coupling in the mid-infrared region.The design strategy for printable inks opens a new pathway toward 3D-printed optoelectronic devices based on functional oxides.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
采用高分子辅助沉积法制备了Si基La BaCo2O5+δ(LBCO)薄膜,主要研究了Si基LBCO薄膜的电输运性质及氧敏性质。通过对LBCO薄膜的电输运性质研究,发现LaBaCo2O5+δ薄膜的激活能Ea为0.32 e V,远小于同类体材料PrBaCo2O5+δ激活能(Ea=0.67 e ...采用高分子辅助沉积法制备了Si基La BaCo2O5+δ(LBCO)薄膜,主要研究了Si基LBCO薄膜的电输运性质及氧敏性质。通过对LBCO薄膜的电输运性质研究,发现LaBaCo2O5+δ薄膜的激活能Ea为0.32 e V,远小于同类体材料PrBaCo2O5+δ激活能(Ea=0.67 e V),说明将材料薄膜化以后,有利于降低材料的激活能;此外,LBCO薄膜阻-温曲线满足小极化子热激化跳跃理论,证明该材料的导电机制是小极化子电子电导。氧敏性质研究发现,在较低的温度356℃下,当测试气体从氢气切换到氧气时,薄膜电阻从3×105Ω迅速下降到4.5×102Ω(ΔR≈3.0×105Ω),响应时间为4.2 s,说明在较低温度下,LBCO薄膜对氧气具有较高的敏感度。同时,发现LBCO薄膜材料导电能力并不与氧气的浓度成正比。展开更多
Printing of metal bottom back electrodes of flexible organic solar cells（FOSCs） at low temperature is of great significance to realize the full-solution fabrication technology. However, this has been difficult to ac...Printing of metal bottom back electrodes of flexible organic solar cells（FOSCs） at low temperature is of great significance to realize the full-solution fabrication technology. However, this has been difficult to achieve because often the interfacial properties of those printed electrodes, including conductivity, roughness, work function,optical and mechanical flexibility, cannot meet the device requirement at the same time. In this work, we fabricate printed Ag and Cu bottom back cathodes by a low-temperature solution technique named polymer-assisted metal deposition（PAMD） on flexible PET substrates. Branched polyethylenimine（PEI） and ZnO thin films are used as the interface modification layers（IMLs） of these cathodes. Detailed experimental studies on the electrical, mechanical, and morphological properties, and simulation study on the optical properties of these IMLs are carried out to understand and optimize the interface of printed cathodes. We demonstrate that the highest power conversion efficiency over 3.0% can be achieved from a full-solution processed OFSC with the device structure being PAMDAg/PEI/P3 HT：PC61BM/PH1000. This device also acquires remarkable stability upon repeating bending tests.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 11028409 and 60976061)the Fundamental Research Funds for the Central Universities of China (Grant No. ZYGX2009Z0001)
文摘Barium titanate（BTO） thin films were deposited on polycrystalline Ni foils by using the polymer assisted deposition（PAD） technique.The growth conditions including ambient and annealing temperatures were carefully optimized based on thermal dynamic analysis to control the oxidation processing and interdiffusion.Crystal structures,surface morphologies,and dielectric performance were examined and compared for BTO thin films annealed under different temperatures.Correlations between the fabrication conditions,microstructures,and dielectric properties were discussed.BTO thin films fabricated under the optimized conditions show good crystalline structure and promising dielectric properties with εr～ 400 and tan δ 〈 0.025 at 100 kHz.The data demonstrate that BTO films grown on polycrystalline Ni substrates by PAD are promising in device applications.
文摘分别用聚合物辅助沉积法和金属有机物分解法制备了WO_3和BiVO_4半导体薄膜电极。利用固体紫外-可见漫反射光谱、电化学阻抗和线性扫描伏安法,对WO_3和BiVO_4半导体薄膜电极的能带结构进行了表征。制备了WO_3/BiVO_4异质结复合光电极,并通过扫描电子显微镜、X射线衍射和X射线光电子能谱,对该复合光电极的断面形貌、晶型结构和物质组成进行了分析。最后,对WO_3/BiVO_4复合光电极的光电转化性能进行了研究。研究结果表明:均为单斜晶型的WO_3和BiVO_4之间形成了膜厚约为450 nm的II型异质结;在施加相对于可逆氢电极1.23 V的电势时,WO_3/BiVO_4光电极的光电流密度可以达到1.926 m A/cm^2,表现出了良好的光电转化性能。
基金Project supported by the National Key Basic Research Program of China(Grant Nos.2015CB921000,2016YFA0300301,2017YFA0303003,and2018YFB0704100)the National Natural Science Foundation of China(Grant Nos.11674374 and 11474338)+2 种基金the Key Research Program of Frontier Sciences of the Chinese Academy of Sciences(Grant No.QYZDB-SSW-SLH008)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grants Nos.XDB07020100 and XDB07030200)the Beijing Municipal Science and Technology Project,China(Grant No.Z161100002116011)
文摘We studied the role of oxygen in Pr2 CuO_(4±δ) thin films fabricated by the polymer assisted deposition method. The magnetoresistance and Hall resistivity of Pr2 CuO_(4±δ) samples were systematically investigated. It was found that with decreasing oxygen content, the low-temperature Hall coefficient(RH) and magnetoresistance changed from negative to positive, similar to those with the increase of Ce-doped concentration in R_(2-x)Ce_x CuO_4 (R = La, Nd, Pr, Sm, Eu). In addition, we observed that the dependence of the superconducting critical temperature Tc with RH for the Pr_(2-x) Ce_x CuO_4 perfectly overlapped with that of Pr_2 CuO_(4±δ) . These findings point to the fact that the doped electrons induced by the oxygen removal are responsible for the superconductivity of the T-phase parent compounds.
基金Fundamental Research Funds for the Central Universities of China (SWJTU09ZT24, SWJTU09BR153)National Natural Science Foundation of China under (50872116)+1 种基金PCSIRT of the Ministry of Education of China (IRT0751)Specialized Research Fund for the Doctoral Program of Higher Education(200806130023)
文摘To increase the critical thickness of CeO2 single buffer layer, the polymer assisted chemical solution deposition (PACSD) approach has been adopted to prepare a single buffer layer of Gd0.3Ce0.7O1.85-x (GCO) on bi-axially textured Ni-5%W alloy substrate, and the influences of different annealing temperatures on texture and microstructure of the buffer layer has also been studied in this paper. The results demonstrate that a well textured, dense and smooth GCO single buffer layer with thickness of 180 nm has been obtained at 1100 ℃ annealing treatment. GdBa2Cu3O7-y (GBCO) film has been deposited on GCO buffered substrate via the similar approach, which is also well textured, dense and smooth. All these show that preparation of GCO buffer layer by PACSD method is an effective approach to prepare single buffer layer for large scale production.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.60976061 and 11028409)
文摘Polymer-assisted deposition technique has been used to deposit Al2O3 and N-doped Al2O3 （AION） thin films on Si（100） substrates. The chemical compositions, crystallinity, and thermal conductivity of the as-grown films have been characterized by X-ray photoelectron spectroscopy （XPS）, X-ray diffraction （XRD）, and 3-omega method, respectively. Amorphous and polycrystalline Al2O3 and AlON thin films have been formed at 700 ℃ and 1000 ℃. The thermal conductivity results indicated that the effect of nitrogen doping on the thermal conductivity is determined by the competition of the increase of Al-N bonding and the suppression of crystallinity. A 67% enhancement in thermal conductivity has been achieved for the samples grown at 700 ℃, demonstrating that the nitrogen doping is an effective way to improve the thermal performance of polymer-assisted-deposited Al2O3 thin films at a relatively low growth temperature.
基金financial support of this research by the National Natural Science Foundation of China (No. 51905446)the Research Center for Industries of the Future (RCIF) at Westlake University for partially supporting this work。
文摘Three-dimensional-structured metal oxides have myriad applications for optoelectronic devices.Comparing to conventional lithography-based manufacturing methods which face significant challenges for 3D device architectures,additive manufacturing approaches such as direct ink writing offer convenient,on-demand manufacturing of 3D oxides with high resolutions down to sub-micrometer scales.However,the lack of a universal ink design strategy greatly limits the choices of printable oxides.Here,a universal,facile synthetic strategy is developed for direct ink writable polymer precursor inks based on metal-polymer coordination effect.Specifically,polyethyleneimine functionalized by ethylenediaminetetraacetic acid is employed as the polymer matrix for adsorbing targeted metal ions.Next,glucose is introduced as a crosslinker for endowing the polymer precursor inks with a thermosetting property required for 3D printing via the Maillard reaction.For demonstrations,binary(i.e.,ZnO,CuO,In_(2)O_(3),Ga_(2)O_(3),TiO_(2),and Y_(2)O_(3)) and ternary metal oxides(i.e.,BaTiO_(3) and SrTiO_(3)) are printed into 3D architectures with sub-micrometer resolution by extruding the inks through ultrafine nozzles.Upon thermal crosslinking and pyrolysis,the 3D microarchitectures with woodpile geometries exhibit strong light-matter coupling in the mid-infrared region.The design strategy for printable inks opens a new pathway toward 3D-printed optoelectronic devices based on functional oxides.
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.
文摘采用高分子辅助沉积法制备了Si基La BaCo2O5+δ(LBCO)薄膜,主要研究了Si基LBCO薄膜的电输运性质及氧敏性质。通过对LBCO薄膜的电输运性质研究,发现LaBaCo2O5+δ薄膜的激活能Ea为0.32 e V,远小于同类体材料PrBaCo2O5+δ激活能(Ea=0.67 e V),说明将材料薄膜化以后,有利于降低材料的激活能;此外,LBCO薄膜阻-温曲线满足小极化子热激化跳跃理论,证明该材料的导电机制是小极化子电子电导。氧敏性质研究发现,在较低的温度356℃下,当测试气体从氢气切换到氧气时,薄膜电阻从3×105Ω迅速下降到4.5×102Ω(ΔR≈3.0×105Ω),响应时间为4.2 s,说明在较低温度下,LBCO薄膜对氧气具有较高的敏感度。同时,发现LBCO薄膜材料导电能力并不与氧气的浓度成正比。
基金Fundamental Research Funds for the Central Universities of China(SWJTU09ZT24, SWJTU09BR153, SWJTU09CX055, SWJTU11ZT16, SWJTU11ZT31)National Natural Science Foundation(50872116, 51072168, 51102199, 51202202, 51271155)+4 种基金the PCSIRT of the Ministry of Education of China(IRT0751)the Specialized Research Fund for the Doctoral Program of Higher Education(200806130023)National Magnetic Confinement Fusion Science Program(2011GB112001)Program of International S&T Cooperation(S2013ZR0595)Science Foundation of Sichuan Province(2011JY0031, 2011JY0130)
基金supported by the Research Grant Council of Hong Kong(No.PolyUC5015-15G)the Hong Kong Polytechnic University(No.G-SB06)the National Natural Science Foundation of China(Nos.21125316,21434009,51573026)
文摘Printing of metal bottom back electrodes of flexible organic solar cells（FOSCs） at low temperature is of great significance to realize the full-solution fabrication technology. However, this has been difficult to achieve because often the interfacial properties of those printed electrodes, including conductivity, roughness, work function,optical and mechanical flexibility, cannot meet the device requirement at the same time. In this work, we fabricate printed Ag and Cu bottom back cathodes by a low-temperature solution technique named polymer-assisted metal deposition（PAMD） on flexible PET substrates. Branched polyethylenimine（PEI） and ZnO thin films are used as the interface modification layers（IMLs） of these cathodes. Detailed experimental studies on the electrical, mechanical, and morphological properties, and simulation study on the optical properties of these IMLs are carried out to understand and optimize the interface of printed cathodes. We demonstrate that the highest power conversion efficiency over 3.0% can be achieved from a full-solution processed OFSC with the device structure being PAMDAg/PEI/P3 HT：PC61BM/PH1000. This device also acquires remarkable stability upon repeating bending tests.
