Identification of Active Sites on High-Performance Pt/Al2O3 Catalyst for Cryogenic CO Oxidation

ACS Catalysis ◽  
2020 ◽  
Vol 10 (15) ◽  
pp. 8815-8824 ◽  
Author(s):  
Yang Chen ◽  
Yingxin Feng ◽  
Lin Li ◽  
Jingyue Liu ◽  
Xiaoli Pan ◽  
...  
Keyword(s):  
Co Oxidation ◽  
Active Sites ◽  
High Performance ◽  
Al2o3 Catalyst

Identification of active sites in CO oxidation over a Pd/Al2O3 catalyst

2019 ◽  
Vol 21 (33) ◽  
pp. 18128-18137 ◽  
Author(s):  
Kazumasa Murata ◽  
Eleen Eleeda ◽  
Junya Ohyama ◽  
Yuta Yamamoto ◽  
Shigeo Arai ◽  
...  
Keyword(s):  
Co Oxidation ◽  
Surface Structure ◽  
Active Sites ◽  
Pd Nanoparticles ◽  
Structure And Morphology ◽  
Al2o3 Catalyst

The active sites of Pd/Al2O3 catalysts for CO oxidations were identified by investigating the dependence of CO oxidation activities on the surface structure and morphology of Pd nanoparticles.

Role of the FeOxsupport in constructing high-performance Pt/FeOxcatalysts for low-temperature CO oxidation

2016 ◽  
Vol 6 (5) ◽  
pp. 1546-1554 ◽  
Author(s):  
Bin Zheng ◽  
Gang Liu ◽  
Longlong Geng ◽  
Junyan Cui ◽  
Shujie Wu ◽  
...  
Keyword(s):  
Low Temperature ◽  
Co Oxidation ◽  
Oxidation State ◽  
Active Sites ◽  
High Performance ◽  
Pt Nanoparticles ◽  
Catalytic Process ◽  
Low Temperature Co Oxidation

The FeOxsupport not only affects the oxidation state of Pt nanoparticles, but also provides active sites in the catalytic process.

Catalytic Neutralization of Naphthenic Acid from Petroleum Crude Oil by Using Cerium Oxide Catalyst and 2- Methylimidazole in Polyethylene Glycol

2020 ◽  
Vol 13 ◽  
Author(s):  
Norshahidatul Akmar Mohd Shohaimi ◽  
Norfakhriah Jelani ◽  
Ahmad Zamani Ab Halim ◽  
Nor Hakimin Abdullah ◽  
Nurasmat Mohd Shukri
Keyword(s):  
Polyethylene Glycol ◽  
Crude Oil ◽  
Cerium Oxide ◽  
Active Sites ◽  
Naphthenic Acid ◽  
Naphthenic Acids ◽  
Catalyst Loading ◽  
High Concentration ◽  
Oil Refineries ◽  
Al2o3 Catalyst

: The presence of relatively high naphthenic acid in crude oil may contribute to the major corrosion in oil pipelines and distillation units in crude oil refineries. Thus, high concentration Naphthenic Acids crude oil is considered tobe of low quality and is marketed at lower prices. In order to overcome this problem, neutralization method had been developed to reduce the TAN value in crude oil. In this study, crude oil from Petronas Penapisan Melaka was investigated. The parameters studied were reagent concentration, catalyst loading, calcination temperature and reusability of the potential catalyst. Basic chemical used were 2- methylimidazole in polyethylene glycol (PEG 600) with concentration 100, 500 and 1000 ppm. Cerium oxide-based catalysts supported onto alumina prepared with different calcination temperatures. The catalyst was characterized by using Brunauer-Emmett-Teller (BET), Fourier Transform Infrared Spectroscopy (FTIR) and Thermogravimetry Analysis-Differential Thermal Gravity (TGA-DTG) to study physical properties of the catalyst. The Ce/Al2O3 catalyst calcined at 1000°C was the best catalyst due to larger surface area formation which lead to increment of active sites thus will boost the catalytic activity. The result showed that the Ce/Al2O3 catalyst meet Petronas requirement as the TAN value reduced to 0.6 mgKOH/g from original TAN value of 4.22 mgKOH/g. The best reduction of TAN was achieved by using catalyst loading of 0.39% and reagent of 1000 ppm.

Core-shell nanostructured Zn-Co-O@CoS arrays for high-performance hybrid supercapacitors

2021 ◽  
Author(s):  
Yi He ◽  
Lei Xie ◽  
Shixiang Ding ◽  
Yujia Long ◽  
Xinyi Zhou ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Energy Storage ◽  
Active Sites ◽  
High Performance ◽  
Electronic Conductivity ◽  
Wide Distribution ◽  
Energy Storage Materials ◽  
Core Shell ◽  
Storage Materials ◽  
Hybrid Supercapacitors

Although the zinc oxide (ZnO) with wide distribution is one of the most attractive energy storage materials, the low electronic conductivity and insufficient active sites of bulk ZnO increase the...

scholarly journals CO Oxidation Efficiency and Hysteresis Behavior over Mesoporous Pd/SiO2 Catalyst

Catalysts ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 131 ◽  
Author(s):  
Rola Mohammad Al Soubaihi ◽  
Khaled Mohammad Saoud ◽  
Myo Tay Zar Myint ◽  
Mats A. Göthelid ◽  
Joydeep Dutta
Keyword(s):  
Carbon Monoxide ◽  
Catalytic Activity ◽  
Co Oxidation ◽  
Active Sites ◽  
Bond Activation ◽  
Dissociative Adsorption ◽  
High Catalytic Activity ◽  
Good Catalytic Activity ◽  
Pretreatment Conditions ◽  
Oxidation Efficiency

Carbon monoxide (CO) oxidation is considered an important reaction in heterogeneous industrial catalysis and has been extensively studied. Pd supported on SiO2 aerogel catalysts exhibit good catalytic activity toward this reaction owing to their CO bond activation capability and thermal stability. Pd/SiO2 catalysts were investigated using carbon monoxide (CO) oxidation as a model reaction. The catalyst becomes active, and the conversion increases after the temperature reaches the ignition temperature (Tig). A normal hysteresis in carbon monoxide (CO) oxidation has been observed, where the catalysts continue to exhibit high catalytic activity (CO conversion remains at 100%) during the extinction even at temperatures lower than Tig. The catalyst was characterized using BET, TEM, XPS, TGA-DSC, and FTIR. In this work, the influence of pretreatment conditions and stability of the active sites on the catalytic activity and hysteresis is presented. The CO oxidation on the Pd/SiO2 catalyst has been attributed to the dissociative adsorption of molecular oxygen and the activation of the C-O bond, followed by diffusion of adsorbates at Tig to form CO2. Whereas, the hysteresis has been explained by the enhanced stability of the active site caused by thermal effects, pretreatment conditions, Pd-SiO2 support interaction, and PdO formation and decomposition.

scholarly journals Efficient Catalytic Conversion of Polysulfides by Biomimetic Design of “Branch-Leaf” Electrode for High-Energy Sodium–Sulfur Batteries

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Wenyan Du ◽  
Kangqi Shen ◽  
Yuruo Qi ◽  
Wei Gao ◽  
Mengli Tao ◽  
...  
Keyword(s):  
Active Sites ◽  
High Performance ◽  
Electrochemical Reaction ◽  
Molecular Layer ◽  
Specific Capacity ◽  
High Energy ◽  
Reduction Reaction ◽  
Biomimetic Design ◽  
Co Nanoparticles ◽  
Sodium Sulfur

AbstractRechargeable room temperature sodium–sulfur (RT Na–S) batteries are seriously limited by low sulfur utilization and sluggish electrochemical reaction activity of polysulfide intermediates. Herein, a 3D “branch-leaf” biomimetic design proposed for high performance Na–S batteries, where the leaves constructed from Co nanoparticles on carbon nanofibers (CNF) are fully to expose the active sites of Co. The CNF network acts as conductive “branches” to ensure adequate electron and electrolyte supply for the Co leaves. As an effective electrocatalytic battery system, the 3D “branch-leaf” conductive network with abundant active sites and voids can effectively trap polysulfides and provide plentiful electron/ions pathways for electrochemical reaction. DFT calculation reveals that the Co nanoparticles can induce the formation of a unique Co–S–Na molecular layer on the Co surface, which can enable a fast reduction reaction of the polysulfides. Therefore, the prepared “branch-leaf” CNF-L@Co/S electrode exhibits a high initial specific capacity of 1201 mAh g−1 at 0.1 C and superior rate performance.

scholarly journals N, S and Transition-Metal Co-Doped Graphene Nanocomposites as High-Performance Catalyst for Glucose Oxidation in a Direct Glucose Alkaline Fuel Cell

Nanomaterials ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 202
Author(s):  
Yexin Dai ◽  
Jie Ding ◽  
Jingyu Li ◽  
Yang Li ◽  
Yanping Zong ◽  
...  
Keyword(s):  
Fuel Cell ◽  
Active Sites ◽  
High Performance ◽  
Glucose Oxidation ◽  
Alkaline Fuel Cell ◽  
Blank Group ◽  
Graphene Nanocomposites ◽  
Doped Graphene ◽  
One Step ◽  
Hydrothermal Approach

In this work, reduced graphene oxide (rGO) nanocomposites doped with nitrogen (N), sulfur (S) and transitional metal (Ni, Co, Fe) were synthesized by using a simple one-step in-situ hydrothermal approach. Electrochemical characterization showed that rGO-NS-Ni was the most prominent catalyst for glucose oxidation. The current density of the direct glucose alkaline fuel cell (DGAFC) with rGO-NS-Ni as the anode catalyst reached 148.0 mA/cm2, which was 40.82% higher than the blank group. The DGAFC exhibited a maximum power density of 48 W/m2, which was more than 2.08 folds than that of blank group. The catalyst was further characterized by SEM, XPS and Raman. It was speculated that the boosted performance was due to the synergistic effect of N, S-doped rGO and the metallic redox couples, (Ni2+/Ni3+, Co2+/Co3+ and Fe2+/Fe3+), which created more active sites and accelerated electron transfer. This research can provide insights for the development of environmental benign catalysts and promote the application of the DGAFCs.

Densely accessible Fe-Nx active sites decorated mesoporous-carbon-spheres for oxygen reduction towards high performance aluminum-air flow batteries

2021 ◽  
Vol 293 ◽  
pp. 120176
Author(s):  
Xiaogang Fu ◽  
Gaopeng Jiang ◽  
Guobin Wen ◽  
Rui Gao ◽  
Shuang Li ◽  
...  
Keyword(s):  
Oxygen Reduction ◽  
Mesoporous Carbon ◽  
Active Sites ◽  
High Performance ◽  
Air Flow ◽  
Carbon Spheres ◽  
Flow Batteries

scholarly journals Facile Synthesis of Uniform Mesoporous Nb2O5 Micro-Flowers for Enhancing Photodegradation of Methyl Orange

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3783
Author(s):  
Jian-Qing Qiu ◽  
Huan-Qing Xie ◽  
Ya-Hao Wang ◽  
Lan Yu ◽  
Fang-Yuan Wang ◽  
...  
Keyword(s):  
Methyl Orange ◽  
Active Sites ◽  
High Performance ◽  
Diffuse Reflectance Spectroscopy ◽  
X Ray Diffraction ◽  
Flower Structure ◽  
Electron Microscopies ◽  
Bet Method ◽  
One Step ◽  
Catalytic Active Sites

The removal of organic pollutants using green environmental photocatalytic degradation techniques urgently need high-performance catalysts. In this work, a facile one-step hydrothermal technique has been successfully applied to synthesize a Nb2O5 photocatalyst with uniform micro-flower structure for the degradation of methyl orange (MO) under UV irradiation. These nanocatalysts are characterized by transmission and scanning electron microscopies (TEM and SEM), X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) method, and UV-Vis diffuse reflectance spectroscopy (DRS). It is found that the prepared Nb2O5 micro-flowers presents a good crystal phases and consist of 3D hierarchical nanosheets with 400–500 nm in diameter. The surface area is as large as 48.6 m2 g−1. Importantly, the Nb2O5 micro-flowers exhibit superior catalytic activity up to 99.9% for the photodegradation of MO within 20 mins, which is about 60-fold and 4-fold larger than that of without catalysts (W/O) and commercial TiO2 (P25) sample, respectively. This excellent performance may be attributed to 3D porous structure with abundant catalytic active sites.

Sign in / Sign up

Export Citation Format

Share Document