Preparation And Photoelectronic Properties Of Modified Nano-SnO₂ Functional Thin Film

As a clean energy,solar cells were paid more and more attention by people in recent years.Hybrid solar cell is one of them,which both have the advantages of inorganic materials and organic materials.In this article,we obtained a variety of SnO2 nano materials by hydrothermal method,which have diffirent morphology.Then we obtained the corresponding nano-film by sol-gel method.Subsequently,we modified the nano-film by PbS quantum dots.Finally we assembled the hybrid solar cells with diffirent polymers.The main works are as follows:(1)Through the hydrothermal method,we obtained diffirent SnO2 nanoparticles in diffirent morphology by SnCl4·5H2O and SnCl2·2H2O.Then we explore the different reaction conditions.It is concluded that the rise of temperature is beneficial to the production of nanometer microspheres,and little influence on the time.But the extension of time and the rise of temperature are not conducive to the formation of nano-powder.Finally,we obtained SnO2 nano-flower with PVP added.PVP is important to the formation of the good micro-morphology,the appropriate ratio of SnCl4·5H2O and PVP is about 1:1.(2)We obtained the corresponding topography nano thin films on FTO by sol-gel method,and then we analyzed and discussed the influence factors and the best codition.It is concluded that in the preparation of colloid stage,when the proportion of the nanomaterials,ethyl cellulose and terpilenol reached at 1:0.5:10,the adhesion will reach the best effect.In the annealing process,when heating at a rate of 2?3?/min,the adhesion will reach the best effect.(3)We modified the nano-film by chemical bath deposition(CBD)and successive ionic layer adsorption and reaction(SILAR),then we selected the best modification methods.Through the experiment we can get that the SILAR is better than CBD because SILAR is easily synthesized,of high repeatability,and the cost and the toxicity is lower.After that we discussed the influence of PbS quantum dots on the modified nano film by changing the times of sensitizing.It is concluded that with the increase in the number of quantum dots,the range of light absorption was broadened from 350 to 650 nm,and the optical absorption performance was also gradually strengthened.(4)We designed and assembled hybrid solar cells with SnO2 and different polymers to explore the influence of different morphology of nano materials,different polymers,the number of sensitizing,different thickness and other conditions.It is concluded that the conversion efficiency of hybrid solar cell,which assembled by SnO2 nano-flower and P3HT,is the highest.It suggests that the morphology of neat and uniform size is beneficial for the conversion efficiency.We got the highest conversion hybrid solar cell when sensitized for 5 times.But the efficiency will be declined when sensitized too much times,which because of the quantum dot size effect weakened.