• Proceedings of the KAIS Fall Conference
• /
• 2011.12a
• /
• pp.196-199
• /
• 2011

In this study we synthesized mesoporous carbon supported CuO by using mesoporous silica i.e. SBA-15 as the template and cupric nitrate trihydrate ($Cu(NO_3)_23H_2O$)as copper source. The porous CuO was characterized with XRD, TGA, SEM and BET. The result reveals porous CuO has good crystal structure with uniform size of spherical crystal particles. The surface are a ($S_{BET}$) of porous CuO was found to be $153.46m^2g^{-1}$ with a total pore volume ($V_p$)of$0.1516cm^3g^{-1}$ and average pore size of 3.9 nm which was much higher than that of commercial CuO ($S_{BET}$, $7.6m^2g^{-1}$; $V_p$, $0.01cm^3g^{-1}$). The obtained porous CuO was studied for adsorption of $CO_2$and the maximum $CO_2$ adsorption capacity was found to be 67.5 mg/g of the sorbent at $25^{\circ}C$.

• Journal of Powder Materials
• /
• v.27 no.3
• /
• pp.193-197
• /
• 2020

Porous Cu-14 wt% Co with aligned pores is produced by a freeze drying and sintering process. Unidirectional freezing of camphene slurry with CuO-Co₃O₄ powders is conducted, and pores in the frozen specimens are generated by sublimation of the camphene crystals. The dried bodies are hydrogen-reduced at 500℃ and sintered at 800℃ for 1 h. The reduction behavior of the CuO-Co₃O₄ powder mixture is analyzed using a temperature-programmed reduction method in an Ar-10% H₂ atmosphere. The sintered bodies show large and aligned parallel pores in the camphene growth direction. In addition, small pores are distributed around the internal walls of the large pores. The size and fraction of the pores decrease as the amount of solid powder added to the slurry increases. The change in pore characteristics according to the amount of the mixed powder is interpreted to be due to the rearrangement and accumulation behavior of the solid particles in the freezing process of the slurry.

• Resources Recycling
• /
• v.30 no.2
• /
• pp.68-74
• /
• 2021

This study investigated formaldehyde (HCHO) removal by preparing porous supports using domestic low-grade silica coated with Co-ZSM5 and Cu-ZSM5 as the catalysts. First, the sample of the raw material for the support contained 90% silica with quartz crystal phase, which was confirmed as low-grade silica. According to Energy-dispersive X-ray spectroscopy (EDS) and Fourier-transform infrared spectroscopy (FT-IR) analyses, the catalysts, Co-ZSM5 and Cu-ZSM5, were successfully coated on the surface of the porous silica supports. During the removal test of HCHO using the prepared Co-ZSM5 and Cu-ZSM5 coated beads, depending on the reaction temperature, the Co-ZSM5 coated beads exhibited higher removal efficiencies (>97%) than the Cu-ZSM5 beads at 200 ℃. The higher efficiency of the Co-ZSM5 coating may be attributed to its superior surface activity properties (BET surface area and pore volume) that lead to the favorable HCHO decomposition. Therefore, Co-ZSM5 was determined to be the suitable catalyst for removing HCHO as a coating on a porous support fabricated using domestic low-grade silica.

• Journal of the Korean institute of surface engineering
• /
• v.56 no.1
• /
• pp.104-114
• /
• 2023

Three dimensional (3D) porous structures consisting of Cu@CoO core-shell-type nano-dendrites were synthesized and tested as the anode materials in lithium secondary batteries. For this purpose, first, the 3D porous films comprising Cu@Co core-shell-type nano-dendrites with various thicknesses were fabricated through the electrochemical co-deposition of Cu and Co. Then the Co shells were selectively anodized to form Co hydroxides, which was finally dehydrated to get Cu@CoO nanodendrites. The resulting electrodes exhibited very high reversible specific capacity almost 1.4~2.4 times the theoretical capacity of commercial graphite, and excellent capacity retention (~90%@50^th cycle) as compared with those of the existing transition metal oxides. From the analysis of the cumulative irreversible capacity and morphology change during charge/discharge cycling, it proved that the excellent capacity retention was attributed to the unique structural feature of our core-shell structure where only the thin CoO shell participates in the lithium storage. In addition, our electrodes showed a superb rate performance (70.5%@10.8 C-rate), most likely due to the open porous structure of 3D films, large surface area thanks to the dendritic structure, and fast electron transport through Cu core network.

• Journal of the Microelectronics and Packaging Society
• /
• v.25 no.4
• /
• pp.105-109
• /
• 2018

We studied graphene synthesis to porous Cu to improve the characteristics of carbon dioxide reduction of cu. Cu powders were formed through Thermal Chemical Vapor Deposition(TCVD) to Porous Cu/Graphene structures synthesized with graphene. As a result of electrochemical experiments using a 0.1 M $KHCO_3$ electrolyte at an applied potential of -1.0 V to -1.4 V, the current density of Porous Cu/Graphene was 1.8 times higher than that of Porous Cu. As a result of evaluating the product, CO and $H_2$ were generated to Porous Cu electrode. On the other hand, the product of porous Cu/Graphene produced CO, $CH_4$ and $C_2H_4$. It is considered that the graphene causes longer carbon dioxide adsorption time, which means that the intermediates formed during the reaction remain on the electrode surface for a longer time. As a result, it can be concluded that the production reaction of the C2 compound could be continuously performed.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2010.05a
• /
• pp.549-550
• /
• 2010

• Analytical Science and Technology
• /
• v.15 no.3
• /
• pp.256-262
• /
• 2002

After porous filters were manufactured using cordierite powder whose mean paricle size was 200${\mu}m$, they were loaded with catalysts such as $V_2O_5$, CuO and $LaCoO_3$ by vacuum impregnation method. And the NOx/SOx simultaneous removal efficiency was measured by passing NO and $SO_2$ through catalyst-loaded ceramic filters. The cordierite porous filters had the apparent porosity of 61.6%, the compressive strength of 12.3 MPa and the pressure drop of 147 pa at the face velocity of 5 cm/sec. According to the analysis of NO/$SO_2$ simultaneous removal efficiency, perovskite $LaCoO_3$ catalyst was the most efficient for the simultaneous NO and $SO_2$ removal. The $LaCoO_3$ catalyst-loaded filter could remove more than 90% for NO and more than 80% for $SO_2$.

• Applied Chemistry for Engineering
• /
• v.21 no.3
• /
• pp.328-332
• /
• 2010

In this study, porous ZnO sphere and Cu-ZnO composite were synthesized by coprecipitation method in diethylene glycol solvent. The physicochemical properties of as-prepared composite materials were characterized by SEM, XRD, $N_2$-sorption and $H_2$-TPR. A series of porous Cu-ZnO with different Cu contents (0, 6.6, 21.3, 36.4, 54.6, 77.8 wt%) was investigated for CO oxidation activity in a fixed bed reactor system. With increasing Cu content in Cu-ZnO the surface area and micropore volume of Cu-ZnO are decreased and Cu (36.4 wt%)-ZnO shows higher activity for CO oxidation compared to the others.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.16 no.5
• /
• pp.60-67
• /
• 2008

The catalytic filter of Cu-ZSM5/alumina beads was considered to reduce NOx in the urea SCR system. Catalytic support of porous alumina beads with mean pore size $130{\mu}m$ and porosity $75{\sim}83%$ were prepared using foaming and gel-casting method. The Cu-ZSM5 catalysts were coated on the supporting alumina beads using $Cu(NO_3)_2$ by ion exchange method. After a washcoating process was applied to coat 10w% Cu-ZSM5 on porous alumina bead, coating layer was estimated $20{\mu}m$ in thickness. The characterization and the feasibility as a catalytic supports were investigated. And the NOx conversion test in Cu-ZSM5/Alumina Beads filter system was conducted by using Urea as reductants under laboratory test. The NOx conversion was increased as size and porosity of beads and observed more than 95% excellent NOx conversion above $300^{\circ}C$.

• Transactions of the Korean hydrogen and new energy society
• /
• v.17 no.4
• /
• pp.448-453
• /
• 2006

Porous Co-P catalysts electroplated on Cu in chloride based solution with an addition of $NaH_2PO_2$ and glycine were developed for hydrogen generation from alkaline $NaBH_4$ solution. The microstructures of the Co-P catalysts and their hydrogen generation properties were analyzed as a function of cathodic current density and plating time during the electrodeposition. Amorphous Co-P electrodeposits with porous structure was formed on Cu at cathodic current density of $0.05\;A/cm^2$, and showed very high hydrogen generation rate in alkaline $NaBH_4$ solution due to an increase in the surface area of the catalyst as well as the catalytic activity. The Co-P catalyst, which was obtained at cathodic current density of $0.05\;A/cm^2$ for 5 min, exhibited the best hydrogen generation rate of 2290 ml/min.g-catalyst in 1 wt. % NaOH+10 wt. % $NaBH_4$ solution at $30^{\circ}C$.