Fabrication Of Carbon Matrix Composites And Its Effect On Performance Of Perovskite Solar Cells

In view of the unstable chemical properties of the organic hole transport material in the perovskite solar cell and the expensive gold electrode,the purpose of this paper is to prepare a low-cost,chemically stable inorganic hole transport material to replace the expensive organic hole transport materials,at the same time,carbon-based composite materials were prepared as counter electrodes to abandon the use of gold electrodes.In this paper,the Ni-EG chelate/rGO precursor was prepared by metal alkoxide method.Different carbon-based composite materials can be obtained using different experimental process.NiO/rGO,Ni/rGO and Ni/CNTs/rGO composites with different microstructures can be prepared by changing the calcination temperature,time,atmosphere,and adding carbon source during calcination.XRD,SEM and TEM were used to characterize the surface morphology,phase,composition and microstructure of the carbon-based composites prepared by different techniques.By using NiO/rGO as the hole-transporting material,using Ni/rGO and Ni/CNTs/rGO as the counterelectrodes to the perovskite solar cells(PSCs),the effects of different microstructures of carbon-based composite materials on the photovoltaic performance of the PSCs were investigated.By changing the temperature of the Ni-EG chelate/rGO precursor calcined in air atmosphere(one-step calcination),the pure NiO/rGO product can be obtained,and when the calcination temperature is 300°C,the rGO surface can be loaded with nanocrystalline NiO densely,whose particle size is about 5nm.The process of calcining the Ni-EG chelate/rGO precursor is changed,that is,the precursor is first calcined and reduced in H2 atmosphere,and then calcined and oxidized in air atmosphere(two-step calcination),so that the surface of rGO can be loaded with NiO particles about 100 nm in diameter.By changing the calcination temperature of NiEG chelate/rGO precursor in H2 atmosphere,Ni/rGO composites can be prepared,and less Ni/rGO sheet agglomeration is obtained after calcination at 400°C than at 500°C,and Ni particles loaded onto rGO are more uniform.Ni/EG chelate/rGO precursor was calcined in H2 atmosphere while adding dicyandiamide as a carbon source to prepare Ni/CNTs/rGO composites,which can achieve the effect of loading Ni and CNTs on rGO surface simultaneously.This article explores and optimizes the manufacturing process of conventional perovskite solar cells,and describes the relationship between their organizational structure and performance.On this basis,NiO/rGO prepared by one-step calcination and two-step calcination was used as a hole-transport material in the perovskite solar cell device respectively.The results showed that NiO/rGO based on one-step calcination(300°C/1h,air atmosphere)using as a hole transport layer has cell efficiency of 4.13%,which has enabled the successful application of NiO/rGO composites in perovskite solar cells.Ni/rGO prepared by calcining Ni-EG chelate/rGO precursor at 400°C and 500°C in H2 atmosphere was used as the counter electrode,and Ni/CNTs/rGO modified by CNTs was used as the electrode material of PSCs,the results show that Ni/rGO prepared by calcining at 400°C can form good interface with the perovskite layer,and the corresponding efficiency reaches 4.24%.