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209. Rational Design of High Surface Area Mesoporous Ni/CeO2 for Partial Oxidation of Propane.

Author

Peymani, Mohammad, Alavi, Seyed Mehdi, Arandiyan, Hamidreza, and Rezaei, Mehran

Subjects
PARTIAL oxidation, PROPANE, NICKEL catalysts
Abstract

A Ni loaded catalyst on mesoporous ceria, with a large surface area, prepared through the surfactant-assisted precipitation and impregnation method was investigated as an efficient catalyst for propane partial oxidation to produce synthesis gas. The results show that 2.5 wt% Ni/CeO2 had the optimum Ni loading, exhibiting the highest catalytic propane conversion. It also showed excellent stability, with no obvious activity drop after a 10 h time-on-stream reaction and slightly decreased in H2 and CO yields. The investigation of the reactant composition effect on carbon formation showed that by decreasing the C/O2 ratio the content of accumulated carbon decreased and propane conversion increased. The good activity of the Ni/CeO2 can be ascribed to the high surface area and rich surface defects of the ceria support and a high dispersion of active sites (Ni nanoparticles). [ABSTRACT FROM AUTHOR]

Published
2018
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210. Template‐free Scalable Synthesis of Flower‐like Co3‐xMnxO4 Spinel Catalysts for Toluene Oxidation.

Author

Wang, Yuan, Arandiyan, Hamidreza, Liu, Yuxi, Liang, Yijing, Peng, Yue, Bartlett, Stuart, Dai, Hongxing, Rostamnia, Sadegh, and Li, Junhua

Subjects
*SPINEL, *CATALYSTS, *TOLUENE, *OXIDATION, *DANDELIONS
Abstract

Abstract: The rational design of low‐cost transition metal catalysts that exhibit high activity and selectivity may be the most significantly investigated in heterogeneous catalysis. In this study, Co3‐xMnxO4 (x=0.75, 1.0, and 1.5) mixed metal oxides were successfully synthesized by a controlled template‐free autoclave strategy and studied for toluene oxidation. It is found that the Co‐rich sample showed markedly enhanced activity and the 3D dandelion‐like Co2.25Mn0.75O4 catalyst exhibited in the highest toluene oxidation rate (8.9 μmol/(gcats)) and a 100 % toluene conversion at 239 °C. In situ DRIFTS study indicates that toluene was sequentially oxidized to benzyl radical, benzaldehyde, benzene, oxalic acid, and finally to CO2 and H2O. The interaction between Co and Mn, in conjunction with the high concentration of surface oxygen species and rich surface oxygen vacancies, reasonably explains the elevated catalytic activity and thermal stability for toluene oxidation over 3D flower‐like Co3‐xMnxO4 spinel catalysts. [ABSTRACT FROM AUTHOR]

Published
2018
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211. One-pot synthesis of S-doped Fe2O3/C magnetic nanocomposite as an adsorbent for anionic dye removal: equilibrium and kinetic studies.

Author

Khoshsang, Hossein, Ghaffarinejad, Ali, Kazemi, Hojjat, Wang, Yuan, and Arandiyan, Hamidreza

Subjects
NANOCOMPOSITE materials, SORBENTS, NANOPARTICLES, CHEMICALS, AQUEOUS solutions
Abstract

Abstract: Novel S-doped Fe2O3/C nanocomposite was synthesized via a one-pot hydrothermal method and was used for the first time as an efficient adsorbent for Congo red dye (CR) removal from water solution. The obtained catalyst was characterized by various methods including Fourier transform infrared spectroscopy, energy dispersive X-ray spectrometry, vibration sample magnetometry, X-ray diffraction and field emission scanning electron microscopy. To improve the adsorption performance, some important parameters affecting dye removal were optimized such as adsorbent dosage, contact time, solution pH, initial dye concentration and ionic strength. At the optimum conditions, the maximum capacity of adsorption for this nanocomposite was 270.2 mg g−1, which is better than other magnetic adsorbents for CR removal. The results of adsorption isotherm were matched with Langmuir model. Kinetic tests show that adsorption experimental data were best fitted by pseudo-first-order model.Graphical abstract: [ABSTRACT FROM AUTHOR]

Published
2018
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213. Tuning SnO2Surface Area for Catalytic Toluene Deep Oxidation: On the Inherent Factors Determining the Reactivity

Author

Liu, Yaqian, Liu, Yang, Guo, Yao, Xu, Junwei, Xu, Xianglan, Fang, Xiuzhong, Liu, Jianjun, Chen, Weifan, Arandiyan, Hamidreza, and Wang, Xiang

Abstract

To understand the fundamental aspects of SnO2catalytic materials and develop applicable catalysts for VOCs combustion, SnO2samples possessing stable and varied surface areas are controllably constructed and applied to toluene deep oxidation. By improving SnO2surface area, the Sn4+cation exposure is improved, thus increasing its surface acidity, which benefits toluene molecule adsorption and activation. Furthermore, more surface defects can be generated, hence inducing the generation of more abundant surface active oxygen sites, which is favorable for further oxidizing the adsorbed and activated toluene intermediates. Therefore, the intrinsic activity of SnO2is eventually promoted. The coexistence of both kinds of active sites is crucial for the reaction, and the concerted interaction between them controls the reaction performance. Catalysts with good activity, superior stability, and potent water vapor tolerance can be achieved by controllably constructing SnO2possessing large and stable surface areas, and supporting less amount of Pd onto it.

Published
2018
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214. Impact of doping ZrO2with Sn on CO2hydrogenation over dispersed Ru

Author

Zhao, Jiajia, Wang, Yuan, Arandiyan, Hamidreza, D'Angelo, Anita M., Seeber, Aaron, Shah, Daksh, Caruso, Rachel A., Cole, Ivan S., Yang, Yunxia, Wilson, Karen, Lippi, Renata, and Lee, Adam F.

Abstract

Thermocatalytic CO2hydrogenation is a scalable route to renewable fuels and chemicals that can also mitigate climate change. Here, we demonstrate how subtle changes in a mixed phase zirconia support induce large changes in catalyst activity and selectivity. Ru/SnxZr1-xO2catalysts were prepared using co-precipitated Sn-doped ZrO2. Ru/ZrO2and Ru/Sn0.01Zr0.99O2both comprised tetragonal (t-) and monoclinic (m-) ZrO2nanoparticles decorated by RuO2·H2O clusters. Ru/Sn0.2Zr0.8O2exhibited similar textural properties and metal speciation, however, X-ray diffraction evidenced new crystalline phases wherein Sn atoms substituted for Zr. Operando XRD evidenced minimal perturbation of ZrO2and Sn-doped ZrO2phases, despite which 20 atom% Sn switched product selectivity from 99% CH4for Ru/ZrO2to 67% CO for Ru/Sn0.2Zr0.8O2, due to increased support CO2adsorption capacity/strength. Operando infrared spectroscopy identify linear surface CO* as a catalytic spectator with (bi)carbonate a precursor to reactive HCOO*/carboxylate intermediates to methane. Sn0.2Zr0.8O2promotes CO2/(bi)carbonate/formate decomposition, favouring a reverse water gas shift pathway.

Published
2023
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217. Well-Constructed Single-Layer Molybdenum Disulfide Nanorose Cross-Linked by Three Dimensional-Reduced Graphene Oxide Network for Superior Water Splitting and Lithium Storage Property

Author

Zhao, Yanyan, primary, Kuai, Long, additional, Liu, Yanguo, additional, Wang, Pengpeng, additional, Arandiyan, Hamidreza, additional, Cao, Sufeng, additional, Zhang, Jie, additional, Li, Fengyun, additional, Wang, Qing, additional, Geng, Baoyou, additional, and Sun, Hongyu, additional

Published
2015
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223. Correlating morphology and doping effects with the carbon monoxide catalytic activity of Zn doped CeO2nanocrystalsElectronic supplementary information (ESI) available. See DOI: 10.1039/c7cy01999h

Author

DuThese authors contributed equally to this work., Haiwei, Wang, Yuan, Arandiyan, Hamidreza, Scott, Jason, Wan, Tao, and Chu, Dewei

Abstract

The effects of Zn-doping on CeO2nanocrystals were investigated for the catalytic oxidation of carbon monoxide (CO). Incorporating Zn2+into CeO2nanocubes with an isotropic 3D structure can effectively regulate oxygen vacancy concentration, compared with CeO2nanorods showing an anisotropic one dimensional 1D structure. The catalytic activity was shown to be governed by a morphology-dependent doping effect.

Published
2018
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226. Synthesis and catalytic advantage of a hierarchical ordered macroporous KIT-6 silica

Author

Siles-Quesada, Sabina, Parlett, Christopher M.A., Lamb, Alexander C., Manayil, Jinesh C., Liu, Yang, Mensah, Jim, Arandiyan, Hamidreza, Wilson, Karen, and Lee, Adam F.

Abstract

Ordered mesoporous silicas are important technological materials in catalysis, sorption and separation science, however new architectures are desired to improve in-pore accessibility. Here we report the first synthesis of an ordered macroporous KIT-6, obtained by optimizing the ratios of Pluronic P123: sodium dodecyl sulfate cosurfactants, and a 400 nm polystyrene nanosphere macropore template. The macroporous KIT-6 possesses 370 nm macropores in a face-centered cubic arrangement, surrounded by a silica framework comprised of cubic Ia3¯dthree-dimensional, intertwined 5 nm mesopore channels. Propylsulfonic acid (PrSO3H) functionalization affords a macroporous KIT-6 solid acid catalyst whose hierarchical pore network permits rapid diffusion and esterification of fatty acids, conferring a five-fold enhancement for palmitic acid esterification compared with a conventional mesoporous PrSO3H/KIT-6, and 33% rate enhancement vs. an ordered macroporous PrSO3H/SBA-15.

Published
2023
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227. Tailored Fabrication of Defect-Rich Ion Implanted CeO2-xNanoflakes for Electrochemical Sensing of H2O2

Author

Luo, Yueyue, Zheng, Xiaoran, Vutukuri, Corey Venkata, Ho, Naomi, Atanacio, Armand J., Manohar, Madhura, Arandiyan, Hamidreza, Wang, Yuan, Sorrell, C.C., S. Mofarah, Sajjad, and Koshy, Pramod

Abstract

As an alternative to H2O2enzymatic biosensing devices, non-enzymatic CeO2-based biosensors have shown improved sensibility, robustness, and shelf lives. The redox capability in CeO2and rapid switching between its oxidation states facilitate the formation of structural vacancy defects that serve as active sites. This work reports a novel approach for synthesis of defect-rich CeO2-x-based nanoflakes using a controllable electrochemical-based deposition at low temperatures (45°−65 °C) followed by low-energy ion implantation. Among the nanoflakes, Mo-implanted CeO2-xexhibited outstanding sensitivity of 4.96 × 10−5 A·mM−1cm−2within the linear range of 0.05–10 mM. Moreover, the ion-implanted samples yielded high sensing stability and electronic conductivity. The former was achieved through the multi-valence charge transfer between Ce and the implanted ions that caused the reduction of Gibbs free energies required for the formation/retention of the defects. The latter was due to the narrowing of the electronic bandgap of CeO2-xby creation of defect-induced midgap states.

Published
2023
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232. BackMatter.

Author

Arandiyan, Hamidreza

Published
2015

234. FrontMatter.

Author

Arandiyan, Hamidreza

Published
2015

242. Interfacial insights into 3D plasmonic multijunction nanoarchitecture toward efficient photocatalytic performance.

Author

Ji, Kemeng, Arandiyan, Hamidreza, Liu, Pan, Zhang, Ling, Han, Jiuhui, Xue, Yacong, Hou, Jungang, and Dai, Hongxing

Abstract

Through effectively harvesting and converting solar energy, photocatalysis has become one of the most important technologies in wastewater decontamination and hydrogen production. Currently, extensive studies are being conducted to develop photocatalysts with advanced features, such as visible-light response, heterogeneous nanoarchitecture, plasmonic effect, and excellent optical behavior. Finding efficient utilization technique to improve photocatalytic performance motivates researchers all over the world. Herein, we demonstrate the design of a visible-light-driven Pd/Fe 2 O 3 /BiVO 4 hybrid with 3D ordered macro-/mesoporous (3DOM) nanoarchitecture for efficiently photocatalytic organic degradation and photoelectrochemical (PEC) water splitting. The hybrid photocatalyst exhibited two-tier bandgap energies and possessed enhanced ability to harvest visible light and separate photo-induced carriers. It is shown that, over the Pd/Fe 2 O 3 /3DOM-BiVO 4 photocatalyst, not only the refractory phenol could be rapidly degraded into CO 2 and H 2 O, but also the photoconversion efficiency was greatly improved in water splitting to generate H 2 . The excellent photocatalytic performance of Pd/Fe 2 O 3 /BiVO 4 was associated with the construction of low-crystalline plasmonic heterointerfaces through the 3DOM framework. The produced synergistic action enabled the hybrid material to absorb the sunlight adequately and transfer the photoexcited carriers expediently to drive phenol degradation or hydrogen evolution from water. [ABSTRACT FROM AUTHOR]

Published
2016
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250. Utilization of spray-dried nanoporous gamma alumina support in biodiesel production from waste cooking oil

Author

Khanbolouk, Faraz, Akia, Mandana, Arandiyan, Hamidreza, Yazdani, Farshad, and Dortaj, Yasin

Abstract

Gamma alumina is one of the widely used supports in catalyst preparation, possessing a high specific surface area and good thermal stability. Spray drying is an efficient way to produce narrow particle size distribution and spherical shape powders. In this study, spray drying method has been implemented to prepare microspherical nanoporous gamma alumina with a high specific surface area. The nanoporous gamma alumina support was utilized in the preparation of various heterogeneous base catalysts. The highest biodiesel yield of 99% was obtained at 6 wt% loading of K/γ-Al2O3catalyst, using waste cooking oil as feedstock. The obtained results revealed the great potential of the synthesized nanoporous gamma alumina as an effective support for heterogeneous base catalysts preparation in the transesterification reaction.

Published
2017
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