Investigation On The Microstructure And Photoelectric Properties Of Pyrite

FeS2, known as Pyrite, is abundant in the crust.The theoretical light absorption coefficient of FeS2 is higher(λ<750nm 时,α>6×105cm-1) and the standard value(Eg)of the forbidden band width is 0.95 eV,this means the FeS2 is the environment-friendly semiconductor material.Thus,FeS2 has been researched since it was found at1950 s.FeS2 has understanding contributions in the production of the thermal and lithium battery electrode materials, and it has excellent properties in photovoltaic performance.Meanwhile, FeS2 is expected to make the suction light material of solar cell. However, the photoelectric performance and photoelectric conversion efficiency of FeS2 are not ideal in the actual research experiments.Aiming at the problem from the photoelectric performance, comprehensive analysis of the preparation of the photoelectric conversion efficiency of the sample.Firstly,this work simulates the forming mechanism of natural pyrite, and uses the hot vulcanization method to compound the FeS2 powder. The synthesis temperatures are 593 K, 613 K, 633 K, 653 K, 673 K and 693 K, respectively. Utilizing the X-ray powder diffraction, scanning electron microscope and the spectrometer to test samples of different curing temperature to get the crystal structure of FeS2, the stoichiometric ratio of S/Fe.Secondly,the light absorption spectra of samples are tested by the ultraviolet visible spectrophotometer, the image is obviously divided into three parts: the weak absorption, linear absorption and saturated absorption. With temperature rising, the saturation light absorption coefficient is gradually decreased. According to the light absorption spectra, it obtains the forbidden band width of the sample by the extension method for absorption edge tangent.Again, the sample is made into square and installed four electrodes, the carrier concentration, carrier mobility, hall coefficient and resistivity under different curing temperatures are measured by the hall effect test system. With temperature rising, the carrier concentration density increases, but the carrier mobility, hall coefficient and resistance rate decreases.At last,comprehensive analysis of the photoelectric properties of pyrite experimental data, it is demonstrated that the photoelectric conversion efficiency ofFeS2 compounded under 633 K curing temperature is the optimum.