The Experts below are selected from a list of 66549 Experts worldwide ranked by ideXlab platform
C. N. R. Rao - One of the best experts on this subject based on the ideXlab platform.
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Solution processed Reduced Graphene Oxide ultraviolet detector
Applied Physics Letters, 2011Co-Authors: Basant Chitara, S. B. Krupanidhi, C. N. R. RaoAbstract:Electronic properties of Graphene have been studied more extensively than its photonic applications, in spite of its exciting optical properties. Recent results on solar cells, light emitting diodes and photodetectors show its true potential in photonics and optoelectronics. Here, we have explored the use of Reduced Graphene Oxide as a candidate for solution processed ultraviolet photodetectors. UV detection is demonstrated by Reduced Graphene Oxide in terms of time resolved photocurrent as well as photoresponse. The responsivity of the detectors is found to be 0.12 A/W with an external quantum efficiency of 40%. (C) 2011 American Institute of Physics. [doi:10.1063/1.3640222]
Fuchi Wang - One of the best experts on this subject based on the ideXlab platform.
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A novel fabrication method of copper–Reduced Graphene Oxide composites with highly aligned Reduced Graphene Oxide and highly anisotropic thermal conductivity
RSC Advances, 2019Co-Authors: Faisal Nazeer, Lihong Gao, Muhammad Abubaker Khan, Abdul Malik, Yitong Xie, Fuchi WangAbstract:Recently, metals with Graphene and Graphene Oxide have been extensively used to enhance the mechanical and anisotropic thermal properties of composites. A novel facile fabrication approach of layer by layer self-assembly followed by hot press sintering was adopted to make copper–Reduced Graphene Oxide composites. The microstructure and heat dissipation properties of pure copper and copper–Reduced Graphene Oxide composites were analyzed with the help of SEM and continuous laser machine analysis. Thermal diffusivity of pure copper and copper–Reduced Graphene Oxide composites was examined in different directions to measure the anisotropic thermal properties by using different volumetric percentages of Reduced Graphene Oxide in the composites. Extraordinarily high anisotropic thermal conductivity of the copper–Reduced Graphene Oxide composites was obtained at a very low concentration of 0.8 vol% Reduced Graphene Oxide, with the difference between the thermal conductivity in-plane and through-plane being a factor of 8.82. Laser test results confirmed the highly anisotropic behavior of our copper–Reduced Graphene Oxide composite with the remarkable property of heat dissipation. The three point bending test was also performed to check the flexural strength of the composites. At 0.6 vol% rGO, the flexural strength was noted (∼127 MPa), and it is 22% higher than that of pure sintered Cu. The high value of anisotropic thermal conductivity and higher flexural strength exhibited by the copper–Reduced Graphene Oxide composite produced using a simple two-step fabrication method give us new hope to use these materials as heat sinks in thermal packaging systems.
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Thermal and mechanical properties of copper-graphite and copper-Reduced Graphene Oxide composites
Composites Part B-engineering, 2019Co-Authors: Faisal Nazeer, Lihong Gao, Muhammad Abubaker Khan, Zhuang Ma, Fuchi Wang, Abdul MalikAbstract:Abstract Graphene and its derivatives have a high value of thermal conductivity and good mechanical properties. Rare studies focused on the anisotropic thermal conductivity, while anisotropic thermal conductivity and hardness of Reduced Graphene Oxide/metal are still far behind the expected values. In this work, different mesh sizes of graphite and Graphene Oxide were used for making copper-graphite and copper-Reduced Graphene Oxide composites with the powder metallurgy technique. Raman, XRD, XPS and SEM were performed to evaluate the disorder, phase analysis, surface morphology and microstructure evolution of the composites as well as synthesized Graphene Oxide. Anisotropic thermal conductivity and Vickers hardness of the composites were characterized to check the effects of different mesh size on copper-graphite and copper-Reduced Graphene Oxide composite. Results show that anisotropic thermal conductivity in-plane and through-plane ratio (1.68) and hardness (71.2 HV) which is 80% and 61% greater than pure copper were attained at only 1 wt% Graphene Oxide mesh size 3500 μm copper-Reduced Graphene Oxide composite. Moreover, graphite and Graphene Oxide mesh size (3500 μm) gave good results compared with mesh sizes 500 μm and 1000 μm. The good anisotropic thermal conductivity and high hardness suggest that it may be ideal materials as heat sinks in thermal packaging.
Abdul Malik - One of the best experts on this subject based on the ideXlab platform.
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A novel fabrication method of copper–Reduced Graphene Oxide composites with highly aligned Reduced Graphene Oxide and highly anisotropic thermal conductivity
RSC Advances, 2019Co-Authors: Faisal Nazeer, Lihong Gao, Muhammad Abubaker Khan, Abdul Malik, Yitong Xie, Fuchi WangAbstract:Recently, metals with Graphene and Graphene Oxide have been extensively used to enhance the mechanical and anisotropic thermal properties of composites. A novel facile fabrication approach of layer by layer self-assembly followed by hot press sintering was adopted to make copper–Reduced Graphene Oxide composites. The microstructure and heat dissipation properties of pure copper and copper–Reduced Graphene Oxide composites were analyzed with the help of SEM and continuous laser machine analysis. Thermal diffusivity of pure copper and copper–Reduced Graphene Oxide composites was examined in different directions to measure the anisotropic thermal properties by using different volumetric percentages of Reduced Graphene Oxide in the composites. Extraordinarily high anisotropic thermal conductivity of the copper–Reduced Graphene Oxide composites was obtained at a very low concentration of 0.8 vol% Reduced Graphene Oxide, with the difference between the thermal conductivity in-plane and through-plane being a factor of 8.82. Laser test results confirmed the highly anisotropic behavior of our copper–Reduced Graphene Oxide composite with the remarkable property of heat dissipation. The three point bending test was also performed to check the flexural strength of the composites. At 0.6 vol% rGO, the flexural strength was noted (∼127 MPa), and it is 22% higher than that of pure sintered Cu. The high value of anisotropic thermal conductivity and higher flexural strength exhibited by the copper–Reduced Graphene Oxide composite produced using a simple two-step fabrication method give us new hope to use these materials as heat sinks in thermal packaging systems.
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Thermal and mechanical properties of copper-graphite and copper-Reduced Graphene Oxide composites
Composites Part B-engineering, 2019Co-Authors: Faisal Nazeer, Lihong Gao, Muhammad Abubaker Khan, Zhuang Ma, Fuchi Wang, Abdul MalikAbstract:Abstract Graphene and its derivatives have a high value of thermal conductivity and good mechanical properties. Rare studies focused on the anisotropic thermal conductivity, while anisotropic thermal conductivity and hardness of Reduced Graphene Oxide/metal are still far behind the expected values. In this work, different mesh sizes of graphite and Graphene Oxide were used for making copper-graphite and copper-Reduced Graphene Oxide composites with the powder metallurgy technique. Raman, XRD, XPS and SEM were performed to evaluate the disorder, phase analysis, surface morphology and microstructure evolution of the composites as well as synthesized Graphene Oxide. Anisotropic thermal conductivity and Vickers hardness of the composites were characterized to check the effects of different mesh size on copper-graphite and copper-Reduced Graphene Oxide composite. Results show that anisotropic thermal conductivity in-plane and through-plane ratio (1.68) and hardness (71.2 HV) which is 80% and 61% greater than pure copper were attained at only 1 wt% Graphene Oxide mesh size 3500 μm copper-Reduced Graphene Oxide composite. Moreover, graphite and Graphene Oxide mesh size (3500 μm) gave good results compared with mesh sizes 500 μm and 1000 μm. The good anisotropic thermal conductivity and high hardness suggest that it may be ideal materials as heat sinks in thermal packaging.
Faisal Nazeer - One of the best experts on this subject based on the ideXlab platform.
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A novel fabrication method of copper–Reduced Graphene Oxide composites with highly aligned Reduced Graphene Oxide and highly anisotropic thermal conductivity
RSC Advances, 2019Co-Authors: Faisal Nazeer, Lihong Gao, Muhammad Abubaker Khan, Abdul Malik, Yitong Xie, Fuchi WangAbstract:Recently, metals with Graphene and Graphene Oxide have been extensively used to enhance the mechanical and anisotropic thermal properties of composites. A novel facile fabrication approach of layer by layer self-assembly followed by hot press sintering was adopted to make copper–Reduced Graphene Oxide composites. The microstructure and heat dissipation properties of pure copper and copper–Reduced Graphene Oxide composites were analyzed with the help of SEM and continuous laser machine analysis. Thermal diffusivity of pure copper and copper–Reduced Graphene Oxide composites was examined in different directions to measure the anisotropic thermal properties by using different volumetric percentages of Reduced Graphene Oxide in the composites. Extraordinarily high anisotropic thermal conductivity of the copper–Reduced Graphene Oxide composites was obtained at a very low concentration of 0.8 vol% Reduced Graphene Oxide, with the difference between the thermal conductivity in-plane and through-plane being a factor of 8.82. Laser test results confirmed the highly anisotropic behavior of our copper–Reduced Graphene Oxide composite with the remarkable property of heat dissipation. The three point bending test was also performed to check the flexural strength of the composites. At 0.6 vol% rGO, the flexural strength was noted (∼127 MPa), and it is 22% higher than that of pure sintered Cu. The high value of anisotropic thermal conductivity and higher flexural strength exhibited by the copper–Reduced Graphene Oxide composite produced using a simple two-step fabrication method give us new hope to use these materials as heat sinks in thermal packaging systems.
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Thermal and mechanical properties of copper-graphite and copper-Reduced Graphene Oxide composites
Composites Part B-engineering, 2019Co-Authors: Faisal Nazeer, Lihong Gao, Muhammad Abubaker Khan, Zhuang Ma, Fuchi Wang, Abdul MalikAbstract:Abstract Graphene and its derivatives have a high value of thermal conductivity and good mechanical properties. Rare studies focused on the anisotropic thermal conductivity, while anisotropic thermal conductivity and hardness of Reduced Graphene Oxide/metal are still far behind the expected values. In this work, different mesh sizes of graphite and Graphene Oxide were used for making copper-graphite and copper-Reduced Graphene Oxide composites with the powder metallurgy technique. Raman, XRD, XPS and SEM were performed to evaluate the disorder, phase analysis, surface morphology and microstructure evolution of the composites as well as synthesized Graphene Oxide. Anisotropic thermal conductivity and Vickers hardness of the composites were characterized to check the effects of different mesh size on copper-graphite and copper-Reduced Graphene Oxide composite. Results show that anisotropic thermal conductivity in-plane and through-plane ratio (1.68) and hardness (71.2 HV) which is 80% and 61% greater than pure copper were attained at only 1 wt% Graphene Oxide mesh size 3500 μm copper-Reduced Graphene Oxide composite. Moreover, graphite and Graphene Oxide mesh size (3500 μm) gave good results compared with mesh sizes 500 μm and 1000 μm. The good anisotropic thermal conductivity and high hardness suggest that it may be ideal materials as heat sinks in thermal packaging.
Basant Chitara - One of the best experts on this subject based on the ideXlab platform.
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Solution processed Reduced Graphene Oxide ultraviolet detector
Applied Physics Letters, 2011Co-Authors: Basant Chitara, S. B. Krupanidhi, C. N. R. RaoAbstract:Electronic properties of Graphene have been studied more extensively than its photonic applications, in spite of its exciting optical properties. Recent results on solar cells, light emitting diodes and photodetectors show its true potential in photonics and optoelectronics. Here, we have explored the use of Reduced Graphene Oxide as a candidate for solution processed ultraviolet photodetectors. UV detection is demonstrated by Reduced Graphene Oxide in terms of time resolved photocurrent as well as photoresponse. The responsivity of the detectors is found to be 0.12 A/W with an external quantum efficiency of 40%. (C) 2011 American Institute of Physics. [doi:10.1063/1.3640222]
