Interaction between BiPbSrCaCuO powder and ambient atmosphere

Interaction between BiPbSrCaCuO powders for fabricating (Bi,Pb)₂Sr₂Ca₂Cu₃O_x superconductors synthesized by different methods and different ambient atmosphere during grinding and the effect on superconductivity have been systematically studied by Fourier transition infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES). It is shown that grinding of powders in air causes the powders to chemically adsorb CO₂ and H₂O from the air while no chemical adsorption occurs in argon. The mechanisms of the interaction have been shown to be related with the Bi₂Sr₂CaCu₂O_x (2212) phase and are discussed based on the structural characteristics of the 2212 phase. Our results highlight the necessity to handle BiPbSrCaCuO powder in an inactive atmosphere such as argon to realize the best superconductivity.