Structure and spectroscopy of CuH preparedviaborohydride reduction

Abstract

Copper(I) hydride (cuprous hydride, CuH) was the first binary metal hydride to be discovered (in 1844) and is singular in that it is synthesized in solution, at ambient temperature. There are several synthetic paths to CuH, one of which involves reduction of an aqueous solution of CuSO 4 Á5H 2 O by borohydride ions. The product from this procedure has not been extensively characterized. Using a combination of diffraction methods (X-ray and neutron) and inelastic neutron scattering spectroscopy, we show that the CuH from the borohydride route has the same bulk structure as CuH produced by other routes. Our work shows that the product consists of a core of CuH with a shell of water and that this may be largely replaced by ethanol. This offers the possibility of modifying the properties of CuH produced by aqueous routes.

Solid-state Thermoelectric Characteristics of NiII, FeII, CoII, and CuII Borohydrides

“…On the other hand, metal borides (M-Bs) [26][27][28][29][30][31][32][33][34] and metal borohydrides (M-BHs) [35][36][37][38][39][40][41][42][43][44][45] of p-, d-, and f-block elements have become in the spotlight as solid-state materials.…”

“…Currently, the exceptional structural, hardness and thermal properties of M-Bs receive increasing attention as hard refractory (TiB6), hard magnets (Nd2Fe14B), battery electrodes, conducting ceramics (ZrB2, HfB2), electro-catalysis, and superconducting (MgB2) materials [26][27][28][29][30][31][32][33][34]. Meanwhile, solid-state M-BHs continue to attract attention as H-storage materials in solid fuels, electrolytes in batteries, and luminescence and magnetic applications [35][36][37][38][39][40][41][42]. Given these characteristics, both M-BHs and M-Bs are anticipated to play a key role in the future's sustainable energy.…”

“…In general, MT-BHs are synthesized in various compositions, structures, and properties, as exemplified by their general chemical formula of Mx(BHn)y [36,38]. In this work, the desired MT-BHs were prepared by mixing the desired metal salt with fourfold excess of NaBH4 in a nonaqueous DMF/MeOH solvent system, Equation 5 [38][39][40][41][42][43][44][45]. This complex reaction process is generally affected by the MT:BH4¯ ratio, solvent, pH, and slow/rapid mixing of reagents.…”

“…This complex reaction process is generally affected by the MT:BH4¯ ratio, solvent, pH, and slow/rapid mixing of reagents. Due to the presence of traces of moisture, two main side reactions may be encountered during the reaction, the formation of metallic element (MT 0 ) and metal oxides /borates (MTO, MTBO3 Equation 6 [39,43,45]. To overcome these possible side reactions, our reactions were carried out in DMF/MeOH solvent mixtures using excess NaBH4.…”

Vibrational spectroscopy with neutrons: Recent developments

“…One possibility is that this is present as CuH, copper (I) hydride. CuH has been known for almost 200 years [32], but has only recently been fully characterized [33][34][35][36]. One of the major puzzles was why CuH synthesized by aqueous methods (denoted as CuH/Würtz) differed so much from CuH synthesized from organic donor solvents (denoted as CuH/pyridine).…”