Study On The Preparation And Properties Of Biomass Carbon Based Metal Composites

In recent years,with the development of science and technology,the exploitation of energy is becoming more and more serious,which leads to the gradual depletion of non-renewable resources in nature.In order to solve this technical problem,more and more researchers began to use biomass as an important carbon source.Biomass is a renewable carbon source,but also has the advantages of small environmental pollution,renewable,wide distribution and so on.In this paper,we try to use biomass to prepare nano composite materials or control magnetic metal oxide,and the gas sensing properties and magnetic properties of the materials are studied.Butterfly wings as template,a kind of biomass carbon based metal composite material C-Co₃O₄ was prepared by hydrothermal synthesis method.Three different Co⁺content?1.20,1.79,and 2.41 mmol?load butterfly wings form the precursor of Co₃O₄ in the hydrothermal process.Nine samples is designated as S1,S2,S3,S4,S5,S6,S7,S8,and S9-Co₃O₄@C after different calcination temperature treatment?350?,400?,450??.To demonstrate the gas sensing performance of the S-Co₃O₄@C,the sensitivity to methanol is carried out under 100ppm methanol atmosphere at different operating temperatures?150?,170?,190?,230??.The results show that the optimal operating temperature of the nine samples is 170?,and the gas sensitivity of the sample S3-Co₃O₄@C is the best,the sensitivity is 11,the response and recovery time is 36 and 41s.In order to verify the sample S3-Co₃O₄@C load butterfly wings is helpful to improve the gas sensing performance,so the pure Co₃O₄?noted as S3-Co₃O₄?was synthesized by the same method as S3-Co₃O₄@C except adding butterfly wings.The sensitivity of the sample S3-Co₃O₄ is 5.7,the response and recovery time is 59 and 48s after the gas sensitivity test.It can be concluded that the butterfly skeleton is beneficial to improve the gas sensing performance.The hydrothermal reaction of cobalt salt precursor is regulated by silk protein as an activator,get the magnetic oxide?Co₃O₄?.The effect of the precursor on the morphology and magnetic properties of magnetic oxide Co₃O₄ at different calcination temperatures is studied.Compared with the magnetic oxide obtained from the reaction system without silk protein,silk protein could not be added into the carbon source,but the magnetic properties of the oxides could be improved effectively.The magnetic properties of Co₃O_4-pro-350? compared with other samples is the best.The saturation magnetization?Ms?of Co₃O_4-pro-350? is 1.8046 emu/g,the coercivity?Hc?of Co₃O_4-pro-350? is 205.54 Oe,and the residual magnetization?Mr?of Co₃O_4-pro-350? is 0.2163 emu/g.