In this study, the mechanical properties (tensile strength, elongation at break and folding resistance) of edible biopolymer film blends formed from blended cassava starch and rice flour at different compositions wi...In this study, the mechanical properties (tensile strength, elongation at break and folding resistance) of edible biopolymer film blends formed from blended cassava starch and rice flour at different compositions with sorbital used as a plasticizer. A suitable ratio of cassava starch and rice flour to water at 10% w/v was used to form a film solution. The addition of a plasticizer agent up to 30% w/w of blending compositions improved the mechanical properties of the generated films. The mechanical properties of the edible blended films with 30% plasticizer were strongly dependent on the blending compositions. Our results pointed out that the cassava starch and rice flour films at a ratio of 70:30 with sorbitol 30% (w/w) had the highest tensile strength which related to folding endurance of the films.展开更多
Mechanical properties of micro-structured porous silicon film (PS) were studied combining X-ray diffraction with micro-Raman spectroscopy. The micro-structured porous silicon samples with different porosities rangin...Mechanical properties of micro-structured porous silicon film (PS) were studied combining X-ray diffraction with micro-Raman spectroscopy. The micro-structured porous silicon samples with different porosities ranging from 30.7700 to 96.2500 were obtained by chemical etching. Lattice parameters of the samples were measured using X-ray diffraction and its maximal change is up to (1.000.) This lattice mismatch with the bulk silicon substrate may introduce residual stress to the porous film. The residual stress measurement by micro-Raman spectroscopy reveals that the maximum of tensile residual stress has reached GPa level in the porous film. Moreover, the lattice mismatch and its corresponding residual stress are increasing with the porosity of PS, but average (elastic) modulus is about 14.5 GPa, one order of magnitude lower than that of substrate Si. The mechanical properties of PS have a close relation with its micro-pore structure.展开更多
The power conversion effciency(PCE)of flexible perovskite solar cells(PSCs)has increased rapidly,while the mechanical flexibility and environmental stability are still far from satisfactory.Previous studies show the e...The power conversion effciency(PCE)of flexible perovskite solar cells(PSCs)has increased rapidly,while the mechanical flexibility and environmental stability are still far from satisfactory.Previous studies show the environmental degradation and ductile cracks of perovskite films usually begin at the grain boundaries(GBs).Herein,sulfonated graphene oxide(s-GO)is employed to construct a cementitious GBs by interacting with the[Pb I6]4–at GBs.The resultant s-GO-[Pb I6]4–complex can effectively passivate the defects of vacant iodine,and the devices with s-GO exhibit remarkable waterproofness and flexibility due to the tough and water-insoluble GBs.The champion PCE of 20.56%(1.01 cm^(2))in a device treated with s-GO is achieved.This device retains 90%of its original PCE after 180 d stored in the ambient condition,as well as over 80%retention after 10,000 bending cycles at a curvature radius of 3 mm.展开更多
文摘In this study, the mechanical properties (tensile strength, elongation at break and folding resistance) of edible biopolymer film blends formed from blended cassava starch and rice flour at different compositions with sorbital used as a plasticizer. A suitable ratio of cassava starch and rice flour to water at 10% w/v was used to form a film solution. The addition of a plasticizer agent up to 30% w/w of blending compositions improved the mechanical properties of the generated films. The mechanical properties of the edible blended films with 30% plasticizer were strongly dependent on the blending compositions. Our results pointed out that the cassava starch and rice flour films at a ratio of 70:30 with sorbitol 30% (w/w) had the highest tensile strength which related to folding endurance of the films.
文摘Mechanical properties of micro-structured porous silicon film (PS) were studied combining X-ray diffraction with micro-Raman spectroscopy. The micro-structured porous silicon samples with different porosities ranging from 30.7700 to 96.2500 were obtained by chemical etching. Lattice parameters of the samples were measured using X-ray diffraction and its maximal change is up to (1.000.) This lattice mismatch with the bulk silicon substrate may introduce residual stress to the porous film. The residual stress measurement by micro-Raman spectroscopy reveals that the maximum of tensile residual stress has reached GPa level in the porous film. Moreover, the lattice mismatch and its corresponding residual stress are increasing with the porosity of PS, but average (elastic) modulus is about 14.5 GPa, one order of magnitude lower than that of substrate Si. The mechanical properties of PS have a close relation with its micro-pore structure.
基金support from the National Natural Science Foundation of China(NSFC)(51673091,51833004,and 51425304)NSFC-Guangdong Joint funding(U1801256)+2 种基金support from the National Key R&D Program of China(2018YFA0208501)the National Natural Science Foundation of China(51803217,91963212,51961145102,and 51773206)K.C.Wong Education Foundation。
文摘The power conversion effciency(PCE)of flexible perovskite solar cells(PSCs)has increased rapidly,while the mechanical flexibility and environmental stability are still far from satisfactory.Previous studies show the environmental degradation and ductile cracks of perovskite films usually begin at the grain boundaries(GBs).Herein,sulfonated graphene oxide(s-GO)is employed to construct a cementitious GBs by interacting with the[Pb I6]4–at GBs.The resultant s-GO-[Pb I6]4–complex can effectively passivate the defects of vacant iodine,and the devices with s-GO exhibit remarkable waterproofness and flexibility due to the tough and water-insoluble GBs.The champion PCE of 20.56%(1.01 cm^(2))in a device treated with s-GO is achieved.This device retains 90%of its original PCE after 180 d stored in the ambient condition,as well as over 80%retention after 10,000 bending cycles at a curvature radius of 3 mm.