Ultrafine beryllium (Be) powder of high purity was successfully synthesized by the pyrolysis of high-puritydi-tbutylberyllium etherate (t-Bu2Be center dot Et2O) in elevated solvent. Scanning electron microscopy (SEM) shows that the powder is near-spherical: The most probable size of Be powder slightly decreases from 1.8 mu m to 1.2 mu m when the pyrolysis temperature increases from 202 degrees C to 214 degrees C and obviously decreases to 0.4 mu m as further increases to 230 degrees C. X-ray diffraction (XRD) indicates that the powder has a single phase of alpha-Be with average crystallite size of 19.8 nm-21.5 nm. The total content of metal impurities in the powder is 6.8 ppm-94.0 ppm by inductively coupled plasma (ICP) determination. (C) 2017 Elsevier B.V. All rights reserved.