The Experts below are selected from a list of 183 Experts worldwide ranked by ideXlab platform
Yinning Zhou - One of the best experts on this subject based on the ideXlab platform.
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synthesis and characterization of polyfluorene based Photoelectric Materials the effect of coil segment on the spectral stability
RSC Advances, 2014Co-Authors: Jinjin Li, Jianjian Wang, Yinning ZhouAbstract:The origin of the low-energy emission of fluorene-based rod-coil block copolymers still remains controversial. In this work, a series of polyfluorene-based rod-coil block copolymers having different coil segments, i.e., poly[2,7-(9,9-dihexylfluorene)]-block-poly(2,2,3,3,4,4,4-heptafluorobutyl methacrylate, (PF-b-PHFBMA), PF-b-poly(butylmethacrylate) (PF-b-PBMA), PF-b-poly(2-hydroxyethyl methacrylate) (PF-b-PHEMA) and PF-b-poly(acrylic acid) (PF-b-PAA), were synthesized using the ATRP technique. The optical and surface properties and thermal behaviors of these copolymers were systematically investigated. In particular, different thermal treatment conditions, including annealing temperature, annealing time and annealing atmosphere were introduced to study the effect of coil segment on the copolymer spectral stability. The incorporation of PBMA, PHEMA and PAA segments to PF could indeed improve the copolymer spectral stability, while the PHFBMA block brought undesirable low-energy emission. In addition, water contact angle (WCA) measurements of the copolymer films before and after annealing further demonstrated that the low-energy emission of PF-based rod-coil block copolymers was attributed to the molecular aggregation rather than the formation of fluorenone defects.
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the synthesis and enhancement of the surface properties of polyfluorene based Photoelectric Materials by introducing fluoromonomers
RSC Advances, 2013Co-Authors: Jianjian Wang, Yinning Zhou, Ping WangAbstract:A series of fluorene-based rod–coil block copolymers with different lengths of fluorine-containing coil segments (poly[2,7-(9,9-dihexylfluorene)]-block-poly (2,2,3,3,4,4,4-heptafluorobutyl methacrylate), PF-b-PHFBMA) were well designed and successfully synthesized via atom transfer radical polymerization (ATRP). The thermal behavior, optical properties and surface properties of these rod–coil block copolymers were investigated. The thermal properties of the copolymers presented a good thermal stability, while the optical properties did not show a noticeable dependence on the lengths of the coil segments. In addition, they showed a high dependence on the self-assembly behavior in selective solvents. The surface properties were obviously influenced by the structure of the micelles formed in different selective solvents (i.e. THF, CHCl3 and C2F3Cl3). The incorporation of the fluorine-containing coil segments in the polyfluorene-based polymers yielded a low energy surface and various interesting surface morphologies, which gives the polymers many potential applications.
Jianjian Wang - One of the best experts on this subject based on the ideXlab platform.
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synthesis and characterization of polyfluorene based Photoelectric Materials the effect of coil segment on the spectral stability
RSC Advances, 2014Co-Authors: Jinjin Li, Jianjian Wang, Yinning ZhouAbstract:The origin of the low-energy emission of fluorene-based rod-coil block copolymers still remains controversial. In this work, a series of polyfluorene-based rod-coil block copolymers having different coil segments, i.e., poly[2,7-(9,9-dihexylfluorene)]-block-poly(2,2,3,3,4,4,4-heptafluorobutyl methacrylate, (PF-b-PHFBMA), PF-b-poly(butylmethacrylate) (PF-b-PBMA), PF-b-poly(2-hydroxyethyl methacrylate) (PF-b-PHEMA) and PF-b-poly(acrylic acid) (PF-b-PAA), were synthesized using the ATRP technique. The optical and surface properties and thermal behaviors of these copolymers were systematically investigated. In particular, different thermal treatment conditions, including annealing temperature, annealing time and annealing atmosphere were introduced to study the effect of coil segment on the copolymer spectral stability. The incorporation of PBMA, PHEMA and PAA segments to PF could indeed improve the copolymer spectral stability, while the PHFBMA block brought undesirable low-energy emission. In addition, water contact angle (WCA) measurements of the copolymer films before and after annealing further demonstrated that the low-energy emission of PF-based rod-coil block copolymers was attributed to the molecular aggregation rather than the formation of fluorenone defects.
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the synthesis and enhancement of the surface properties of polyfluorene based Photoelectric Materials by introducing fluoromonomers
RSC Advances, 2013Co-Authors: Jianjian Wang, Yinning Zhou, Ping WangAbstract:A series of fluorene-based rod–coil block copolymers with different lengths of fluorine-containing coil segments (poly[2,7-(9,9-dihexylfluorene)]-block-poly (2,2,3,3,4,4,4-heptafluorobutyl methacrylate), PF-b-PHFBMA) were well designed and successfully synthesized via atom transfer radical polymerization (ATRP). The thermal behavior, optical properties and surface properties of these rod–coil block copolymers were investigated. The thermal properties of the copolymers presented a good thermal stability, while the optical properties did not show a noticeable dependence on the lengths of the coil segments. In addition, they showed a high dependence on the self-assembly behavior in selective solvents. The surface properties were obviously influenced by the structure of the micelles formed in different selective solvents (i.e. THF, CHCl3 and C2F3Cl3). The incorporation of the fluorine-containing coil segments in the polyfluorene-based polymers yielded a low energy surface and various interesting surface morphologies, which gives the polymers many potential applications.
Ping Wang - One of the best experts on this subject based on the ideXlab platform.
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the synthesis and enhancement of the surface properties of polyfluorene based Photoelectric Materials by introducing fluoromonomers
RSC Advances, 2013Co-Authors: Jianjian Wang, Yinning Zhou, Ping WangAbstract:A series of fluorene-based rod–coil block copolymers with different lengths of fluorine-containing coil segments (poly[2,7-(9,9-dihexylfluorene)]-block-poly (2,2,3,3,4,4,4-heptafluorobutyl methacrylate), PF-b-PHFBMA) were well designed and successfully synthesized via atom transfer radical polymerization (ATRP). The thermal behavior, optical properties and surface properties of these rod–coil block copolymers were investigated. The thermal properties of the copolymers presented a good thermal stability, while the optical properties did not show a noticeable dependence on the lengths of the coil segments. In addition, they showed a high dependence on the self-assembly behavior in selective solvents. The surface properties were obviously influenced by the structure of the micelles formed in different selective solvents (i.e. THF, CHCl3 and C2F3Cl3). The incorporation of the fluorine-containing coil segments in the polyfluorene-based polymers yielded a low energy surface and various interesting surface morphologies, which gives the polymers many potential applications.
Chunming Wang - One of the best experts on this subject based on the ideXlab platform.
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electrochemical synthesis of zno nanoflowers and nanosheets on porous si as Photoelectric Materials
Applied Surface Science, 2011Co-Authors: Xin Zhang, Yongling Du, Weichun Ye, Chunming WangAbstract:Well-aligned ZnO nanoflowers and nanosheets were synthesized on porous Si (PS) at different applied potentials by electrodeposition approach. The deposits were grown using the optimized program and were characterized by means of cyclic voltammetry (CV), amperometry I-t (I-t), open-circuit potentiometry. X-ray diffraction (XRD) analysis proved a strong preferential orientation (1 0 0) on PS. Scanning electronic microscopy (SEM) observation showed the deposits consist of nanoflowers with uniform grain size of about 100 nm in diameter and nanosheets, which may have potential applications in nanodevices and nanotechnologies. Thus, ZnO grown on PS can be used as Photoelectric Materials due to its larger Photoelectric effect compared to Si wafer according to open-circuit potential (OCP) study. Optical band gap measurements were made on samples using UV–visible spectrophotometer thus giving a band gap of 3.35 eV.
Wangping Xu - One of the best experts on this subject based on the ideXlab platform.
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New Family of Two-Dimensional Group-(II₃–V₂) Photoelectric Materials
The Journal of Physical Chemistry, 2020Co-Authors: Wangping Xu, Rui Wang, Xiaozhi Wu, Hu XuAbstract:Two-dimensional (2D) Materials with direct and modest band gaps and high mobility are desired not only for the intrinsic interest they attract but also for their practical application for optoelectronic devices. In this work, a new family of 2D binary group-(II₃–V₂) Materials, named, X₃Y₂ (X = Mg and Ca and Sr; Y = P and As), was predicted by using high throughput first-principles calculations. Our accurate quasiparticle calculations indicate that these candidates have direct band gaps and excellent optical absorption in the visible region. Moreover, all the proposed 2D X₃Y₂ Materials possess extremely high electron mobility (up to 2.46 × 10⁴ cm² V–¹ s–¹) close to that of phosphorene. In addition, 2D Ca₃P₂ is estimated to have an outstanding power conversion efficiency of 21.1%, suggesting that Ca₃P₂ is a promising donor material for solar cells. Our findings effectively broaden the candidates of 2D photoelectronic Materials.
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new family of two dimensional group ii 3 v 2 Photoelectric Materials
Journal of Physical Chemistry C, 2019Co-Authors: Wangping Xu, Rui Wang, Xiaozhi Wu, Hu XuAbstract:Two-dimensional (2D) Materials with direct and modest band gaps and high mobility are desired not only for the intrinsic interest they attract but also for their practical application for optoelect...
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New Family of Two-Dimensional Group-(II 3 –V 2 ) Photoelectric Materials
Journal of Physical Chemistry C, 2019Co-Authors: Wangping Xu, Rui Wang, Xiaozhi Wu, Hu XuAbstract:Two-dimensional (2D) Materials with direct and modest band gaps and high mobility are desired not only for the intrinsic interest they attract but also for their practical application for optoelect...
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new family of two dimensional ternary Photoelectric Materials
ACS Applied Materials & Interfaces, 2019Co-Authors: Wangping Xu, Rui Wang, Baobing Zheng, Xiaozhi Wu, Hu XuAbstract:Screening unique two-dimensional (2D) Materials with high mobility and applicable band gaps is motivated by not only the interest in basic science but also the practical applications for Photoelectric Materials. In this work, we have systematically studied a new family of 2D ternary quintuple layers (QLs), named ABC (A = Na, K, and Rb; B = Cu, Ag, and Au; C = S, Se, and Te). Our results indicate that the QLs of KCuTe, KAgS, KAgSe, KAuTe, RbCuTe, RbAgSe, and RbAgTe host direct band gaps. Moreover, KCuTe, RbCuTe, and RbAgTe QLs show extremely high mobilities of ∼104 cm2 V–1 s–1. Interestingly, the linear scaling between exciton binding energy and quasiparticle band gap for ABC QLs exhibits an unexpected deviation with the 1/4 law. In addition, KAgSe, KAgS, RbAgSe, and RbAgTe show outstanding power energy conversion efficiencies of up to 21.5%, suggesting that they are good potential donor Materials. Our results provide many potential candidates for applications in Photoelectric Materials, which may be reali...
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new family of two dimensional group ii v Photoelectric Materials
The Journal of Physical Chemistry, 2019Co-Authors: Wangping Xu, Rui Wang, Xiaozhi Wu, Hu XuAbstract:Two-dimensional (2D) Materials with direct and modest band gaps and high mobility are desired not only for the intrinsic interest they attract but also for their practical application for optoelectronic devices. In this work, a new family of 2D binary group-(II₃–V₂) Materials, named, X₃Y₂ (X = Mg and Ca and Sr; Y = P and As), was predicted by using high throughput first-principles calculations. Our accurate quasiparticle calculations indicate that these candidates have direct band gaps and excellent optical absorption in the visible region. Moreover, all the proposed 2D X₃Y₂ Materials possess extremely high electron mobility (up to 2.46 × 10⁴ cm² V–¹ s–¹) close to that of phosphorene. In addition, 2D Ca₃P₂ is estimated to have an outstanding power conversion efficiency of 21.1%, suggesting that Ca₃P₂ is a promising donor material for solar cells. Our findings effectively broaden the candidates of 2D photoelectronic Materials.