In order to build a ceramic component by inkjet printing, the object must be fabricated through the interaction and solidification of drops, typically in the range of 10–100 p L. In order to achieve this goal, stable...In order to build a ceramic component by inkjet printing, the object must be fabricated through the interaction and solidification of drops, typically in the range of 10–100 p L. In order to achieve this goal, stable ceramic inks must be developed. These inks should satisfy specific rheological conditions that can be illustrated within a parameter space defined by the Reynolds and Weber numbers. Printed drops initially deform on impact with a surface by dynamic dissipative processes, but then spread to an equilibrium shape defined by capillarity. We can identify the processes by which these drops interact to form linear features during printing, but there is a poorer level of understanding as to how 2D and 3D structures form. The stability of 2D sheets of ink appears to be possible over a more limited range of process conditions that is seen with the formation of lines. In most cases, the ink solidifies through evaporation and there is a need to control the drying process to eliminate the "coffee ring" defect. Despite these uncertainties, there have been a large number of reports on the successful use of inkjet printing for the manufacture of small ceramic components from a number of different ceramics. This technique offers good prospects as a future manufacturing technique. This review identifies potential areas for future research to improve our understanding of this manufacturing method.展开更多
All-graphene devices are new class of graphene devices with simple layouts and low contact resistances. Here we report a clean fabrication strategy for all-graphene devices via a defect-assisted anisotropic etching. T...All-graphene devices are new class of graphene devices with simple layouts and low contact resistances. Here we report a clean fabrication strategy for all-graphene devices via a defect-assisted anisotropic etching. The as-fabricated graphene is free of contamination and retains the quality of pristine graphene. The contact resistance at room temperature （RT） between a bilayer graphene channel and a multilayer graphene electrode can be as low as -5 Ω.·μm, the lowest ever achieved experimentally. Our results suggest the feasibility of employing such all-graphene devices in high performance carbon-based integrated circuits.展开更多
To date, the cost-effective utilization of solar energy by photovoltaics for large-scale deployment remains challenging. Further cost minimization and efficiency maximization, through reduction of material consumption...To date, the cost-effective utilization of solar energy by photovoltaics for large-scale deployment remains challenging. Further cost minimization and efficiency maximization, through reduction of material consumption, simplification of device fabrication as well as optimization of device structure and geometry, are required. The usage of 1D nanomaterials is attractive due to the outstanding light coupling effect, the ease of fabrication, and integration with one-dimensional(1-D) semiconductor materials. The light absorption efficiency can be enhanced significantly, and the corresponding light-toelectricity conversion efficiency can be as high as their bulk counterparts. Also, the amount of active materials used can be reduced. This review summarizes the recent development of 1-D nanomaterials for photovoltaic applications, including the anti-reflection, the light absorption,the minority diffusion, and the semiconductor junction properties. With solid progress and prospect shown in the past 10 years, 1-D semiconductor nanomaterials are attractive and promising for the realization of high-efficiency and low-cost solar cells.展开更多
文摘In order to build a ceramic component by inkjet printing, the object must be fabricated through the interaction and solidification of drops, typically in the range of 10–100 p L. In order to achieve this goal, stable ceramic inks must be developed. These inks should satisfy specific rheological conditions that can be illustrated within a parameter space defined by the Reynolds and Weber numbers. Printed drops initially deform on impact with a surface by dynamic dissipative processes, but then spread to an equilibrium shape defined by capillarity. We can identify the processes by which these drops interact to form linear features during printing, but there is a poorer level of understanding as to how 2D and 3D structures form. The stability of 2D sheets of ink appears to be possible over a more limited range of process conditions that is seen with the formation of lines. In most cases, the ink solidifies through evaporation and there is a need to control the drying process to eliminate the "coffee ring" defect. Despite these uncertainties, there have been a large number of reports on the successful use of inkjet printing for the manufacture of small ceramic components from a number of different ceramics. This technique offers good prospects as a future manufacturing technique. This review identifies potential areas for future research to improve our understanding of this manufacturing method.
基金This work was supported by the National Basic Research Program of China （973 Program） （Nos. 2013CB934500 and 2013CBA01600）, the National Natural Science Foundation of China （NSFC） （Nos. 61325021, 91223204, 11174333 and 11204358）, and the Chinese Academy of Sciences.
文摘All-graphene devices are new class of graphene devices with simple layouts and low contact resistances. Here we report a clean fabrication strategy for all-graphene devices via a defect-assisted anisotropic etching. The as-fabricated graphene is free of contamination and retains the quality of pristine graphene. The contact resistance at room temperature （RT） between a bilayer graphene channel and a multilayer graphene electrode can be as low as -5 Ω.·μm, the lowest ever achieved experimentally. Our results suggest the feasibility of employing such all-graphene devices in high performance carbon-based integrated circuits.
基金supported by the Early Career Scheme of the Research Grants Council of Hong Kong SARChina(City U 139413)+4 种基金the National Natural Science Foundation of China(51202205 and 61504151)the State Key Laboratory of Multiphase Complex Systems(MPCS-2014-C-01 and MPCS-2015-A-04)the Science Technology and Innovation Committee of Shenzhen Municipality(JCYJ20140419115507588)a Grant from the Shenzhen Research InstituteCity University of Hong Kong
文摘To date, the cost-effective utilization of solar energy by photovoltaics for large-scale deployment remains challenging. Further cost minimization and efficiency maximization, through reduction of material consumption, simplification of device fabrication as well as optimization of device structure and geometry, are required. The usage of 1D nanomaterials is attractive due to the outstanding light coupling effect, the ease of fabrication, and integration with one-dimensional(1-D) semiconductor materials. The light absorption efficiency can be enhanced significantly, and the corresponding light-toelectricity conversion efficiency can be as high as their bulk counterparts. Also, the amount of active materials used can be reduced. This review summarizes the recent development of 1-D nanomaterials for photovoltaic applications, including the anti-reflection, the light absorption,the minority diffusion, and the semiconductor junction properties. With solid progress and prospect shown in the past 10 years, 1-D semiconductor nanomaterials are attractive and promising for the realization of high-efficiency and low-cost solar cells.
