Identification of the chemical states of phosphorus in atmospheric aerosols by XANES spectrometry.
Depth selective XAFS spectrometry was applied to determine the chemical states of phosphorus in atmospheric aerosols. Atmospheric aerosols were collected on aluminum foils and polyethylene films using a 4-stage cascade impactor and a 12-stage low pressure Andersen sampler, respectively. Samplings were performed at Uji (urban area) and Sakurajima (near a volcano). We measured X-ray fluorescence yield (XFY) and total electron yield (sample current) simultaneously to obtain the X-ray absorption near edge structure (XANES) spectra of the atmospheric aerosols. X-ray absorption in the vicinities of P K-edges was measured on the beamline BL-11B at the Photon Factory, High Energy Accelerator Research Organization, Tsukuba, Japan. The Sakurajima aerosol samples showed only a P5+ peak and the peak was remarkable in coarse mode. In case of the Uji samples, the P5+ peak was dominant and a slight P3+ peak was detected for sample current measurement.