The Experts below are selected from a list of 252 Experts worldwide ranked by ideXlab platform
Yucheng Huang - One of the best experts on this subject based on the ideXlab platform.
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Complete Separation of Carriers in the GeS/SnS Lateral Heterostructure by Uniaxial Tensile Strain
ACS applied materials & interfaces, 2017Co-Authors: Lei Peng, Chan Wang, Qi Qian, Sufan Wang, Yucheng HuangAbstract:The strategy of forming lateral heterostructures by stitching various two-dimensional materials overcomes the limitations due to the restricted properties of single-component materials. In this work, by using first-principles calculations, the electronic properties of GeS/SnS lateral heterostructures, together with the effect of strain, were systematically investigated. The results showed that with increasing tensile strain along the zigzag direction the band gap displays an extremely interesting variation: it linearly increases in the beginning until 2.4% strain (region I), then remains nearly constant until 5.7% (region II), and finally linearly decreases within the tensile limit (region III). Meanwhile, the electronic properties successively change from quasi-type II alignment to direct band gap to type II alignment with Complete carrier Separation. Analysis of the densities of states and partial charge densities indicates that the band gap increase in region I is due to the change in the orbital contributions to the states of the conduction band minimum (CBM) from Sn-pz to Sn-px, whereas the band gap decrease in region III is caused by an increasingly loose distribution of antibonding electrons at the CBM. Moreover, it was found that the changes in the orbital constituents from Sn-pz to Sn-px in the CBM and from S-px to S-py in the valence band maximum are responsible for the indirect-direct and direct-indirect band gap crossovers at the junctions of regions I and II and regions II and III, respectively. Finally, through calculations of the carrier concentrations on the basis of deformation potential theory, electrons and holes are demonstrated to be largely separated with the enhancement of strain, and the predicted electron mobilities in the armchair direction at 7% strain are as high as 5860-11 220 cm2 V-1 s-1. We believe our work may lead to potential applications for GeS-SnS heterostructures in electronics, optoelectronics, and straintronics.
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Complete Separation of carriers in the ges sns lateral heterostructure by uniaxial tensile strain
ACS Applied Materials & Interfaces, 2017Co-Authors: Lei Peng, Chan Wang, Qi Qian, Sufan Wang, Yucheng HuangAbstract:The strategy of forming lateral heterostructures by stitching various two-dimensional materials overcomes the limitations due to the restricted properties of single-component materials. In this work, by using first-principles calculations, the electronic properties of GeS/SnS lateral heterostructures, together with the effect of strain, were systematically investigated. The results showed that with increasing tensile strain along the zigzag direction the band gap displays an extremely interesting variation: it linearly increases in the beginning until 2.4% strain (region I), then remains nearly constant until 5.7% (region II), and finally linearly decreases within the tensile limit (region III). Meanwhile, the electronic properties successively change from quasi-type II alignment to direct band gap to type II alignment with Complete carrier Separation. Analysis of the densities of states and partial charge densities indicates that the band gap increase in region I is due to the change in the orbital contr...
Hongbo Chen - One of the best experts on this subject based on the ideXlab platform.
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Complete Separation of Cu(II), Co(II) and Li(I) using self-driven MFCs-MECs with stainless steel mesh cathodes under continuous flow conditions
Separation and Purification Technology, 2015Co-Authors: Dan Wu, Yuzhen Pan, Liping Huang, Peng Zhou, Xie Quan, Hongbo ChenAbstract:Complete Separation of Cu(II), Co(II) and Li(I) each other from aqueous mixtures is one critical step for recycling spent lithium ion batteries, and generally consumes large amount of energy and chemicals. Previous tests have primarily examined fed-batch operated self-driven microbial fuel cells (MFCs)-microbial electrolysis cells (MECs) for Cu(II) and Co(II) recovery. Mixed Cu(0) and Co(0) however, were simultaneously deposited on the MEC cathodes and Co(II) in effluents was much above water quality standard in addition to the lack of considering Li(I) species in actual wastewaters and necessarily optimizing inexpensive stainless steel (SS) as MEC cathodes for system performance. Various mesh size SS was thus explored in self-driven MFCs-MECs with different influent metal concentrations and hydraulic retention times (HRTs) under continuous flow conditions for Complete Separation of Cu(II), Co(II) and Li(I) each other. Mesh #60 achieved the best and Complete Separation of Cu(II), Co(II) and Li(I) each other with an influent metal concentration of 10 mg L-1 Cu(II), 10 mg L-1 Co(II) and 3 mg L-1 Li(I) at an HRT of 9 h. These results demonstrate mesh size of SS as MEC cathodes, HRT and influent metal concentration were critical for Complete Separation of Cu(II), Co(II) and Li(I) each other in self-driven MFCs-MECs under continuous flow conditions.
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Complete Separation of Cu(II), Co(II) and Li(I) using self-driven MFCs–MECs with stainless steel mesh cathodes under continuous flow conditions
Separation and Purification Technology, 2015Co-Authors: Yuzhen Pan, Liping Huang, Peng Zhou, Xie Quan, Hongbo ChenAbstract:Abstract Complete Separation of Cu(II), Co(II) and Li(I) each other from aqueous mixtures is one critical step for recycling spent lithium ion batteries, and generally consumes large amount of energy and chemicals. Previous tests have primarily examined fed-batch operated self-driven microbial fuel cells (MFCs)–microbial electrolysis cells (MECs) for Cu(II) and Co(II) recovery. Mixed Cu(0) and Co(0) however, were simultaneously deposited on the MEC cathodes and Co(II) in effluents was much above water quality standard in addition to the lack of considering Li(I) species in actual wastewaters and necessarily optimizing inexpensive stainless steel (SS) as MEC cathodes for system performance. Various mesh size SS was thus explored in self-driven MFCs–MECs with different influent metal concentrations and hydraulic retention times (HRTs) under continuous flow conditions for Complete Separation of Cu(II), Co(II) and Li(I) each other. Mesh #60 achieved the best and Complete Separation of Cu(II), Co(II) and Li(I) each other with an influent metal concentration of 10 mg L−1 Cu(II), 10 mg L−1 Co(II) and 3 mg L−1 Li(I) at an HRT of 9 h. These results demonstrate mesh size of SS as MEC cathodes, HRT and influent metal concentration were critical for Complete Separation of Cu(II), Co(II) and Li(I) each other in self-driven MFCs–MECs under continuous flow conditions.
Lei Peng - One of the best experts on this subject based on the ideXlab platform.
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Complete Separation of Carriers in the GeS/SnS Lateral Heterostructure by Uniaxial Tensile Strain
ACS applied materials & interfaces, 2017Co-Authors: Lei Peng, Chan Wang, Qi Qian, Sufan Wang, Yucheng HuangAbstract:The strategy of forming lateral heterostructures by stitching various two-dimensional materials overcomes the limitations due to the restricted properties of single-component materials. In this work, by using first-principles calculations, the electronic properties of GeS/SnS lateral heterostructures, together with the effect of strain, were systematically investigated. The results showed that with increasing tensile strain along the zigzag direction the band gap displays an extremely interesting variation: it linearly increases in the beginning until 2.4% strain (region I), then remains nearly constant until 5.7% (region II), and finally linearly decreases within the tensile limit (region III). Meanwhile, the electronic properties successively change from quasi-type II alignment to direct band gap to type II alignment with Complete carrier Separation. Analysis of the densities of states and partial charge densities indicates that the band gap increase in region I is due to the change in the orbital contributions to the states of the conduction band minimum (CBM) from Sn-pz to Sn-px, whereas the band gap decrease in region III is caused by an increasingly loose distribution of antibonding electrons at the CBM. Moreover, it was found that the changes in the orbital constituents from Sn-pz to Sn-px in the CBM and from S-px to S-py in the valence band maximum are responsible for the indirect-direct and direct-indirect band gap crossovers at the junctions of regions I and II and regions II and III, respectively. Finally, through calculations of the carrier concentrations on the basis of deformation potential theory, electrons and holes are demonstrated to be largely separated with the enhancement of strain, and the predicted electron mobilities in the armchair direction at 7% strain are as high as 5860-11 220 cm2 V-1 s-1. We believe our work may lead to potential applications for GeS-SnS heterostructures in electronics, optoelectronics, and straintronics.
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Complete Separation of carriers in the ges sns lateral heterostructure by uniaxial tensile strain
ACS Applied Materials & Interfaces, 2017Co-Authors: Lei Peng, Chan Wang, Qi Qian, Sufan Wang, Yucheng HuangAbstract:The strategy of forming lateral heterostructures by stitching various two-dimensional materials overcomes the limitations due to the restricted properties of single-component materials. In this work, by using first-principles calculations, the electronic properties of GeS/SnS lateral heterostructures, together with the effect of strain, were systematically investigated. The results showed that with increasing tensile strain along the zigzag direction the band gap displays an extremely interesting variation: it linearly increases in the beginning until 2.4% strain (region I), then remains nearly constant until 5.7% (region II), and finally linearly decreases within the tensile limit (region III). Meanwhile, the electronic properties successively change from quasi-type II alignment to direct band gap to type II alignment with Complete carrier Separation. Analysis of the densities of states and partial charge densities indicates that the band gap increase in region I is due to the change in the orbital contr...
Marco Mazzotti - One of the best experts on this subject based on the ideXlab platform.
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Equilibrium theory based design of simulated moving bed processes for a generalized Langmuir isotherm
Journal of Chromatography A, 2006Co-Authors: Marco MazzottiAbstract:In the frame of the local equilibrium theory of chromatography, design criteria for Complete Separation of binary mixtures in simulated moving bed (SMB) Separations are developed, presented and discussed. These apply to systems, whose retention behavior is characterized by a generalized Langmuir isotherm. By allowing for negative terms in the denominator of the classical Langmuir isotherm, this newly introduced adsorption model captures a broad class of competitive or synergistic adsorption, including anti-Langmuir behavior for both adsorbates, and mixed cases where one species behaves in a Lagmuirian and the other in an anti-Langmuirian manner. By extending classical equilibrium theory results for the binary Langmuir isotherm, and by generalizing the approach followed earlier to derive SMB design criteria for the binary and multi-component Langmuir isotherm, exact algebraic equations for the boundary of the Complete Separation region in the operating parameter space are derived for all possible generalized Langmuir isotherm. The effect of changing feed composition on the shape of the Complete Separation region and on the position of the optimal operating point is analyzed and discussed.
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Design of Simulated Moving Bed Separations: Generalized Langmuir Isotherm
Industrial & Engineering Chemistry Research, 2006Co-Authors: Marco MazzottiAbstract:In this paper, exact criteria for the Complete Separation of binary mixtures in simulated moving bed (SMB) units are developed. They apply to systems subject to the generalized Langmuir isotherm, whose definition yields four different types of isotherms corresponding to different combinations of Langmuir and anti-Langmuir behavior of the components to be separated. These criteria are derived in a similar way in the different cases using the equilibrium theory of chromatography applied to the equivalent true moving bed (TMB) unit. Separation performance is controlled by the dimensionless flow rate ratios. The Complete Separation region in the operating parameters space has boundaries that are constituted of straight lines and curves, defined through simple and easy-to-use equations. These in turn depend on the adsorption isotherm parameters and on the composition of the feed mixture. The analogies and differences observed among the four isotherms in terms of Complete Separation region are analyzed and discussed.
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Optimal operation of simulated moving-bed units for non-linear chromatographic Separations
Journal of Chromatography A, 1998Co-Authors: Andrea Gentilini, Marco Mazzotti, Cristiano Migliorini, Massimo MorbidelliAbstract:Several important theoretical results have been previously obtained to predict the behaviour of continuous chromatographic Separation units in the case of Langmuirian type of isotherms. Concerning Separation of binary mixtures in a non-adsorbable carrier with SMB units, stoichiometric and non-stoichiometric Langmuir and modified Langmuir have been considered in the frame of equilibrium theory. For these isotherms explicit constraints on the operating parameters have been found to achieve Complete Separation (M. Mazzotti, G. Storti, M. Morbidelli, J. Chromatogr. A 769 (1997) 3; M. Mazzotti, G. Storti, M. Morbidelli, AIChE J, 42 (1996) 2784; M. Mazzotti, M. Pedeferri, M. Morbidelli, in: Chiral Europe '96 Symposium, Spring Innovations Limited, Stockport, UK, 1996); the design of the SMB unit was then reduced to the analysis of the so-called region of Complete Separation for the operating parameters. In this paper, the same result is presented for the bi-Langmuir case, which can avoid the constant selectivity limit of the Langmuir isotherms. Langmuir and bi-langmuir isotherms fitting the same set of data taken from the literature were then used here to show the difference in the prediction of the region of Complete Separation. Finally an analysis of non-linearity effects on performance parameters is presented as a useful criterion for optimization of the Separation performances. (C) 1998 Elsevier Science B.V
Yuzhen Pan - One of the best experts on this subject based on the ideXlab platform.
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Complete Separation of Cu(II), Co(II) and Li(I) using self-driven MFCs-MECs with stainless steel mesh cathodes under continuous flow conditions
Separation and Purification Technology, 2015Co-Authors: Dan Wu, Yuzhen Pan, Liping Huang, Peng Zhou, Xie Quan, Hongbo ChenAbstract:Complete Separation of Cu(II), Co(II) and Li(I) each other from aqueous mixtures is one critical step for recycling spent lithium ion batteries, and generally consumes large amount of energy and chemicals. Previous tests have primarily examined fed-batch operated self-driven microbial fuel cells (MFCs)-microbial electrolysis cells (MECs) for Cu(II) and Co(II) recovery. Mixed Cu(0) and Co(0) however, were simultaneously deposited on the MEC cathodes and Co(II) in effluents was much above water quality standard in addition to the lack of considering Li(I) species in actual wastewaters and necessarily optimizing inexpensive stainless steel (SS) as MEC cathodes for system performance. Various mesh size SS was thus explored in self-driven MFCs-MECs with different influent metal concentrations and hydraulic retention times (HRTs) under continuous flow conditions for Complete Separation of Cu(II), Co(II) and Li(I) each other. Mesh #60 achieved the best and Complete Separation of Cu(II), Co(II) and Li(I) each other with an influent metal concentration of 10 mg L-1 Cu(II), 10 mg L-1 Co(II) and 3 mg L-1 Li(I) at an HRT of 9 h. These results demonstrate mesh size of SS as MEC cathodes, HRT and influent metal concentration were critical for Complete Separation of Cu(II), Co(II) and Li(I) each other in self-driven MFCs-MECs under continuous flow conditions.
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Complete Separation of Cu(II), Co(II) and Li(I) using self-driven MFCs–MECs with stainless steel mesh cathodes under continuous flow conditions
Separation and Purification Technology, 2015Co-Authors: Yuzhen Pan, Liping Huang, Peng Zhou, Xie Quan, Hongbo ChenAbstract:Abstract Complete Separation of Cu(II), Co(II) and Li(I) each other from aqueous mixtures is one critical step for recycling spent lithium ion batteries, and generally consumes large amount of energy and chemicals. Previous tests have primarily examined fed-batch operated self-driven microbial fuel cells (MFCs)–microbial electrolysis cells (MECs) for Cu(II) and Co(II) recovery. Mixed Cu(0) and Co(0) however, were simultaneously deposited on the MEC cathodes and Co(II) in effluents was much above water quality standard in addition to the lack of considering Li(I) species in actual wastewaters and necessarily optimizing inexpensive stainless steel (SS) as MEC cathodes for system performance. Various mesh size SS was thus explored in self-driven MFCs–MECs with different influent metal concentrations and hydraulic retention times (HRTs) under continuous flow conditions for Complete Separation of Cu(II), Co(II) and Li(I) each other. Mesh #60 achieved the best and Complete Separation of Cu(II), Co(II) and Li(I) each other with an influent metal concentration of 10 mg L−1 Cu(II), 10 mg L−1 Co(II) and 3 mg L−1 Li(I) at an HRT of 9 h. These results demonstrate mesh size of SS as MEC cathodes, HRT and influent metal concentration were critical for Complete Separation of Cu(II), Co(II) and Li(I) each other in self-driven MFCs–MECs under continuous flow conditions.