The preparation of large crystals is highly important for the characterization and application of a newly found structure but remains a challenge for one-dimensional(1D)C_(60) polymers.In this work,we successfully fab...The preparation of large crystals is highly important for the characterization and application of a newly found structure but remains a challenge for one-dimensional(1D)C_(60) polymers.In this work,we successfully fabricated a 1D C_(60) polymer crystal via on-site annealing of a millimeter-sized C_(60) molecular crystal withα-Li_(3)N at 500°C and ambient pres�sure.Characterizations show that the C_(60) cages in the crystal have been efficiently connected,forming 1D chains along the<110>direction in an orthorhombic 3D structure.At the same time,the crystal maintains a morphology similar to that of the pristine C_(60)crystal,providing opportunities for characterization of all the facets of the crystal via Raman spectroscopy and thus suggesting the formation mechanism of such crystals.展开更多
Ternary strategy has demonstrated great potential in promoting the power conversion efficiency(PCE)of bulk heterojunction organic solar cells(BHJ OSCs).Two new polymer donors,TPQ-2 F-2 Cl and TPQ-2 F-4 F,were synthesi...Ternary strategy has demonstrated great potential in promoting the power conversion efficiency(PCE)of bulk heterojunction organic solar cells(BHJ OSCs).Two new polymer donors,TPQ-2 F-2 Cl and TPQ-2 F-4 F,were synthesized with chlorinated and fluorinated aromatic side chains,respectively,which contributed to distinct noncovalent interactions.Compared with the PM 6:L 8-BO host system,the TPQ-2 F-2 Cl based ternary OSCs obtained enhanced exciton dissociation and more balanced carrier mobility.Moreover,benefiting from the favorable miscibility of the PM 6:L 8-BO:TPQ-2 F-2 Cl blend,the ternary blending film featured a well-defined fibrillar morphology and improved molecular ordering.Consequently,the optimal PM 6:L 8-BO:TPQ-2 F-2 Cl device achieved a more outstanding PCE of 18.2%,a higher open circuit voltage(V_(oc)),and a better fill factor(FF)in comparison with the binary device(PCE=17.7%).In contrast,the addition of TPQ-2 F-4 F would generate excessive aggregation of blend,thereby reducing the PCE of ternary OSCs(16.0%).This work shows a promising idea for designing efficient third component donor polymers.展开更多
For the investigation of mechanical properties of the bimrocks with high rock block proportion,a series of laboratory experiments,including resonance frequency and uniaxial compressive tests,are conducted on the 64 fa...For the investigation of mechanical properties of the bimrocks with high rock block proportion,a series of laboratory experiments,including resonance frequency and uniaxial compressive tests,are conducted on the 64 fabricated bimrocks specimens.The results demonstrate that dynamic elastic modulus is strongly correlated with the uniaxial compressive strength,elastic modulus and block proportions of the bimrocks.In addition,the density of the bimrocks has a good correlation with the mechanical properties of cases with varying block proportions.Thus,three crucial indices(including matrix strength)are used as basic input parameters for the prediction of the mechanical properties of the bimrocks.Other than adopting the traditional simple regression and multi-regression analyses,a new prediction model based on the optimized general regression neural network(GRNN)algorithm is proposed.Note that,the performance of the multi-regression prediction model is better than that of the simple regression model,owing to the consideration of various influencing factors.However,the comparison between model predictions indicates that the optimized GRNN model performs better than the multi-regression model does.Model validation and verification based on fabricated data and experimental data from the literature are performed to verify the predictability and applicability of the proposed optimized GRNN model.展开更多
基金supported by the National Key R&D Program of China(2020YFA0711502)the National Natural Science Foundation of China(52325202,52202052,52373310)。
文摘The preparation of large crystals is highly important for the characterization and application of a newly found structure but remains a challenge for one-dimensional(1D)C_(60) polymers.In this work,we successfully fabricated a 1D C_(60) polymer crystal via on-site annealing of a millimeter-sized C_(60) molecular crystal withα-Li_(3)N at 500°C and ambient pres�sure.Characterizations show that the C_(60) cages in the crystal have been efficiently connected,forming 1D chains along the<110>direction in an orthorhombic 3D structure.At the same time,the crystal maintains a morphology similar to that of the pristine C_(60)crystal,providing opportunities for characterization of all the facets of the crystal via Raman spectroscopy and thus suggesting the formation mechanism of such crystals.
基金Projects(52125306,21875286)supported by the National Natural Science Foundation of China。
文摘Ternary strategy has demonstrated great potential in promoting the power conversion efficiency(PCE)of bulk heterojunction organic solar cells(BHJ OSCs).Two new polymer donors,TPQ-2 F-2 Cl and TPQ-2 F-4 F,were synthesized with chlorinated and fluorinated aromatic side chains,respectively,which contributed to distinct noncovalent interactions.Compared with the PM 6:L 8-BO host system,the TPQ-2 F-2 Cl based ternary OSCs obtained enhanced exciton dissociation and more balanced carrier mobility.Moreover,benefiting from the favorable miscibility of the PM 6:L 8-BO:TPQ-2 F-2 Cl blend,the ternary blending film featured a well-defined fibrillar morphology and improved molecular ordering.Consequently,the optimal PM 6:L 8-BO:TPQ-2 F-2 Cl device achieved a more outstanding PCE of 18.2%,a higher open circuit voltage(V_(oc)),and a better fill factor(FF)in comparison with the binary device(PCE=17.7%).In contrast,the addition of TPQ-2 F-4 F would generate excessive aggregation of blend,thereby reducing the PCE of ternary OSCs(16.0%).This work shows a promising idea for designing efficient third component donor polymers.
基金Projects(51978669,U1734208)supported by the National Natural Science Foundation of ChinaProject(2018JJ3657)supported by Natural Science Foundation of Hunan Province,China
文摘For the investigation of mechanical properties of the bimrocks with high rock block proportion,a series of laboratory experiments,including resonance frequency and uniaxial compressive tests,are conducted on the 64 fabricated bimrocks specimens.The results demonstrate that dynamic elastic modulus is strongly correlated with the uniaxial compressive strength,elastic modulus and block proportions of the bimrocks.In addition,the density of the bimrocks has a good correlation with the mechanical properties of cases with varying block proportions.Thus,three crucial indices(including matrix strength)are used as basic input parameters for the prediction of the mechanical properties of the bimrocks.Other than adopting the traditional simple regression and multi-regression analyses,a new prediction model based on the optimized general regression neural network(GRNN)algorithm is proposed.Note that,the performance of the multi-regression prediction model is better than that of the simple regression model,owing to the consideration of various influencing factors.However,the comparison between model predictions indicates that the optimized GRNN model performs better than the multi-regression model does.Model validation and verification based on fabricated data and experimental data from the literature are performed to verify the predictability and applicability of the proposed optimized GRNN model.
