Large-scale synthesis and catalytic activity of nanoporous Cu–O system towards CO oxidation

Abstract

Nanoporous Cu-O system catalysts with different oxidation states of Cu have been fabricated through a combination of dealloying of as-milled Al 66.7 Cu 33.3 alloy powders with subsequent thermal annealing. X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) have been used to characterize the microstructure and surface chemical states of Cu-O catalysts. The peculiar nanoporous structure can be retained in Cu-O catalysts after thermal treatment. Catalytic experiments reveal that all the Cu-O samples exhibit a complete CO 2 conversion below 170 o C. The optimal catalytic performance could be achieved through the combination of annealing in air with hydrogen treatment for the Cu-O catalyst, which shows near complete conversion temperature (T 90% ) of 132 o C and activation energy of 91.3 KJ mol -1 . In addition, the present strategy (ball milling, dealloying and subsequent thermal treatment) could be scaled up to fabricate high-performance Cu-O catalysts towards CO oxidation.

Peroxidase Mimicking of Binary Polyacrylonitrile-CuO Nanoflowers and the Application in Colorimetric Detection of H2O2 and Ascorbic Acid

“…The peaks located at 953.7 and 933.7 eV corresponded to Cu 2p 1/2 and Cu 2p 3/2 , respectively. The gap was 20 eV between the peaks of 933.7 and 953.7 eV, which was consistent with the standard spectrum of copper oxide. − The typical shake-up satellite peaks located at 933.7, 941.0, 943.9, 953.6, and 962.2 eV corresponded to the Cu­(II) state . The O 1s spectrum was resolved into three peaks at 532.2, 531.0, and 529.7 eV (Figure H), which were due to C–O–C, O–H, and Cu–O, respectively. , Therefore, spindle-shaped CuO nanoneedles were formed on the surface of PAN nanoflowers.…”

“…62−64 The typical shake-up satellite peaks located at 933.7, 941.0, 943.9, 953.6, and 962.2 eV corresponded to the Cu(II) state. 65 The O 1s spectrum was resolved into three peaks at 532.2, 531.0, and 529.7 eV (Figure 3H), which were due to C−O−C, O−H, and Cu−O, respectively. 66,67 Therefore, spindle-shaped CuO nanoneedles were formed on the surface of PAN nanoflowers.…”

Single and Dual Metal Oxides as Promising Supports for Carbon Monoxide Removal from an Actual Syngas: The Crucial Role of Support on the Selectivity of the Au–Cu System

“…In-depth descriptions for Cu/CeO 2 [9], AuCu/CeO 2 [29], AuCu/SiO 2 [30], AuCu/Al 2 O 3 [31], Au/Fe 2 O 3 [32], Au/La 2 O 3 /Al 2 O 3 [33], and Au/CeO 2 -ZrO 2 [34,35] are available in the literature. In general, Au favors the CO conversion through a mechanism that involves Au-CO and Au-OOH species [36], where the formation of C-O* intermediates determines the selectivity of the process [20], while CuO acts through a redox mechanism [8], promoting oxygen mobility in the oxide lattice [37] and facilitating the CO oxidation. A synergistic Au-Cu effect has also been proposed [19,29,38].…”

Synthesis and Full Characterization of One Organometallic Polyoxometalate-Based Copper(I)-Alkene Complex

“…The XPS spectra of Mo show two peaks at 235.86 and 232.72 eV (Figure 3a), which are attributed to Mo VI 3d 3/2 and Mo VI 3d 5/2 , respectively. 42 For the Cu spectrum, no typical shake-up satellite peaks are observed, indicating that the Cu centers are in the oxidation state +1, 43,44 and the main peaks at 953.16 and 933.41 eV can be assigned to Cu I 2p 1/2 and Cu I 2p 3/2 , respectively. Thus, the formula of compound 1 should be [(Cu I L) 2 (P V Mo VI 12 O 40 )]•(Cu I L).…”