Designing cheap, earth-abundant, and nontoxic metal catalysts for acetylene hydrogenation is of pivotal importance, but challenging. Here, a nonprecious metal catalyst for selective hydrogenation of acetylene in excess ethylene was prepared from Cu 2 O nanocubes. The preparation includes two steps: (1) thermal treatment in acetylene-containing gas at 160 °C and (2) hydrogen reduction at 180 °C. The resultant catalyst showed outstanding performance at low temperature (80−100 °C) and 0.1−0.5 MPa pressure, completely converting acetylene with a low selectivity to undesired ethane (<20%). The characterization results of high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy corroborated that the formation of an interstitial copper carbide (Cu x C) might give rise to significantly enhanced hydrogenation activity. Preliminary density functional theory calculation demonstrated that the lattice spacing of Cu 3 C was nearly identical to that of the new Cu x C crystallite measured in HRTEM and determined by XRD. The calculated dissociation energy of hydrogen on Cu 3 C(0001) was considerably lower than that on Cu(111), suggesting superior hydrogenation activity of Cu 3 C(0001). It is experimentally verified that copper(I) acetylide (Cu 2 C 2 ) might be the precursor of Cu x C. Cu 2 C 2 underwent partial hydrogenation to fabricate Cu x C crystallites and the thermal decomposition to Cu and carbon materials in parallel.

We report the preparation of a two-dimensional superhydrophobic covalent organic frameworks (COFs) coated cotton fabric by a rapid one-step method under room temperature. This COFs coated fabric was found to...

Replacing precious metals with cheap metals in catalysts is a topic of interest in both industry and academia but challenging. Here, a selective hydrogenation catalyst was prepared by thermal treatment of Cu­(OH)2 nanowires with acetylene-containing gas at 120 °C followed by hydrogen reduction at 150 °C. The characterization by means of transmission electron microscopy observation, X-ray diffraction, and X-ray photoelectron spectroscopy revealed that two crystallites were present in the resultant catalyst. One of the crystal phases was metal Cu, whereas the other crystal phase was ascribed to an interstitial copper carbide (Cu x C) phase. The reduction of freshly prepared copper (II) acetylide (CuC2) at 150 °C also afforded the formation of Cu and Cu x C crystallites, indicating that CuC2 was the precursor or an intermediate in the formation of Cu x C. The prepared catalysts consisting of Cu and Cu x C exhibited a considerably high hydrogenation activity at low temperatures in the selective hydrogenation of acetylene in the ethylene stream. In the presence of a large excess of ethylene, acetylene was completely converted at 110 °C and atmospheric pressure with an ethane selectivity of <15%, and the conversion and selectivity were constant in a 260 h run.