CO Oxidation at Near-Ambient Temperatures over TiO2-Supported Pd-Cu Catalysts: Promoting Effect of Pd-Cu Nanointerface and TiO2 Morphology

Abstract

Significant improvement of the catalytic activity of palladium-based catalysts toward carbon monoxide (CO) oxidation reaction has been achieved through alloying and using different support materials. This work demonstrates the promoting effects of the nanointerface and the morphological features of the support on the CO oxidation reaction using a Pd-Cu/TiO2 catalyst. Pd-Cu catalysts supported on TiO2 were synthesized with wet chemical approaches and their catalytic activities for CO oxidation reaction were evaluated. The physicochemical properties of the prepared catalysts were studied using standard characterization tools including SEM, EDX, XRD, XPS, and Raman. The effects of the nanointerface between Pd and Cu and the morphology of the TiO2 support were investigated using three different-shaped TiO2 nanoparticles, namely spheres, nanotubes, and nanowires. The Pd catalysts that are modified through nanointerfacing with Cu and supported on TiO2 nanowires demonstrated the highest CO oxidation rates, reaching 100% CO conversion at temperature regime down to near-ambient temperatures of ~45 °C, compared to 70 °C and 150 °C in the case of pure Pd and pure Cu counterpart catalysts on the same support, respectively. The optimized Pd-Cu/TiO2 nanowires nanostructured system could serve as efficient and durable catalyst for CO oxidation at near-ambient temperature.

Facile Microwave Synthesis of Hierarchical Porous Copper Oxide and Its Catalytic Activity and Kinetics for Carbon Monoxide Oxidation

“…The TPR findings further support the significance of MW-driven heating in the formation of a hierarchical porous structure with improved physiochemical properties. Thus, the SEM, XRD, BET, TGA, and TPR results confirm that the rational control of morphology and structure of HP-CuO by MWS could modulate the catalyst’s reducibility and catalytic performance. , …”

“…Furthermore, the core-level transitions of the O 1s of chemically adsorbed hydroxide and carbonate species typically appear in the range of 531–532 eV . Accordingly, the peak at 531.5 eV could also be related to the carbonate or polarized oxygen ions adjacent to oxygen (O) vacant sites or bonded oxygen in the used HP-CuO catalyst. , The high BE peak at 531.5 was only observed in the case of the used HP-CuO catalyst, which infers the presence of oxygen vacant sites and indicates their role in the enhanced CO oxidation.…”

“…Supported precious metals including Au, Pt, Pd, Ir, and Ru are key components of many active catalysts for CO oxidation. , Nevertheless, exploring efficient and cost-effective catalysts remains a crucial demand for environmental sustainability. This demand could be reached by developing non-precious materials with improved physical and chemical properties for enhanced catalytic activity . Copper (Cu) is an earth-abundant, inexpensive, and major industrial transition metal.…”

“…This demand could be reached by developing non-precious materials with improved physical and chemical properties for enhanced catalytic activity. 4 Copper (Cu) is an earth-abundant, inexpensive, and major industrial transition metal. In recent years, Cu-based materials have been extensively studied for basic and applied research in various sectors.…”

Electrochemical Reduction of CO2: A Review of Cobalt Based Catalysts for Carbon Dioxide Conversion to Fuels

“…Catalysis plays a vital role in our daily life. Various types of catalysts have been reported for the conversion of waste into useful products, including zeolites [ 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 ], metal and metal oxides [ 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 ], nitrides [ 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 ], carbon-based catalysts [ 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 ], metal complexes [ 64 , …”