Studies of copper hydride. Part 1.—Synthesis and solid-state stability

Abstract

Copper hydride, CuH, has been prepared by the reduction of aqueous copper sulfate using hypophosphorous acid. The polycrystalline red–brown hydride has been analysed using transmission electron microscopy, powder X-ray diffraction (PXRD) and differential scanning calorimetry, and consists of agglomerates of needle-like particles ca. 100 Å in size. It is unstable at room temperature and, in an inert atmosphere, decomposes, as shown by powder XRD, to copper metal and hydrogen. Activation energies of 2.0, 8.5 and 4.7 (±0.4) kcal mol^–1 were obtained for the induction, acceleratory and decay stages of the isothermal decomposition process below 100 °C. Above this temperature the solid melts.