Current Nanoscience (v.11, #1)

Preface by Dae-Joon Kang, Atta-ur-Rahman (i-i).

Catalytic Valorization of Cellulose and Cellobiose with Nanoparticles by Hu Li, Qiuyun Zhang, Anders Riisager, Song Yang (1-14).
Cellulose considered as one of the most abundant renewable resources have great potentialfor the production of bio-fuels and chemical building blocks bearing a diverse range of applications.Among various approaches for the efficient transformation of cellulose, nanoparticles on ordered porousmaterials with high surface area and unique particle morphology employed as heterogeneous catalysts exhibit dramaticimprovement of catalytic activity and selectivity. In this review, selective conversion of cellulose as well as cellobiosethrough different types of reactions including hydrolysis, isomerization, dehydration, hydrogenation/hydrogenolysis, oxidation,hydrogenation-dehydration, and gasification/pyrolysis promoted by mono- or bi-functional nanocatalysts has beendescribed. Emphasis is also paid to discuss plausible reaction pathways catalyzed by functionalized nanoparticles in thesecatalytic processes.

Nanomedicine in Therapeutic Intervention of Tuberculosis Meningitis by Anil K. Sharma, Rohit Sharma, Ramesh Jhorar, Raman Kumar (15-22).
Nanotechnology has shown tremendous scope in healthcare offering numerous possibilities tosignificantly improve diagnosis of many dreadful diseases including Tuberculosis (MTB). Nanomedicinehas made the current drug regimen more effective against tuberculosis particularly tuberculosis meningitiswith attributes like sustained release, increased half life, higher drug concentrations at target sites, reducedtoxicity and lesser side effects. However because of the severity of the disease, there is a strong urge to develop better approacheswith some concomitant regimens using nano-particles to diagnose, treat and manage tuberculosis meningitis(TBM) patients. The rate of drug resistance is also reportedly higher in case of TBM, which may further reduce the patientcompliance and therapeutic failure of the current regimen. Hence there is an urgent need to develop effective ways tocounter TBM. The current review highlights some of the evolving strategies in the field of nanomedicine offering promisingalternatives to the existing TBM regimens. The study also emphasizes upon the need to design more effective biocompatibleand biodegradable nanocarriers which can effectively cross the blood brain barrier to counter TBM.

Carbon Nanotubes Characterization by X-ray Powder Diffraction - A Review by Rasel Das, Sharifah Bee Abd Hamid, Md. Eaqub Ali, Seeram Ramakrishna, Wu Yongzhi (23-35).
Carbon nanotubes have been increasingly used in the fields of nanorobotics, electrochemicalcatalysis, microarray chips, and green adsorbents for pollutants, sensors and optoelectronics. Complicatedphysico-chemical aspects and novel schemes to synthesize controlled featured carbon nanotubes have added new ambiguitiesto their characterizations and applications and these must be resolved on an urgent basis. Most of the characterizationtools such as scanning electron microscopy, transmission electron microscopy, scanning tunneling microscopy and atomicforce microscopy probes only for characterizing the local features of carbon nanotubes. However, X-ray powder diffractioncan reveal the local and global features of microstructure's lattice and crystalline phases, domain sizes, and impurities.Thus it is worthwhile to highlight this technique for better understanding and utilization of its benefit to unravel thecarbon nanotube ambiguities. To the best of our knowledge, no comprehensive reviews or systematic description of X-raypowder diffraction on carbon nanotubes characterization have been published yet. In this review, we filled-up this gap andprovided a systematic presentation of X-ray powder diffraction application in carbon nanotubes characterization. Thiscould be used as a reference guide for the utilization of X-ray powder diffraction to probe the various features of carbonnanotubes and carbon nanotubes based materials.

An Active CNTFET Model for RF Characterization Deduced from S Parameters Measurements by Roberto Marani, Gennaro Gelao, Pasquale Soldano, Anna Gina Perri (36-40).
In this paper a procedure for RF characterization of Carbon NanoTube Field Effect Transistors is illustrated andapplied to a back-gate CNTFET. S parameters measurements up to 12 GHz are performed and a new lumped element activetwo-port network is proposed and deduced from these measurements. To obtain the intrinsic RF behavior of the device,we perform a straightforward static de-embedding procedure, applicable to any other CNTFET structures. In thisway it is possible to evaluate the intrinsic model to implement directly in simulation software for electronic circuits CAD.

Multifunctional Hybrid Nanocomposite Nanofibers Produced by Colloid Electrospinning from Water Solutions by Alessio Varesano, Claudia Vineis, Cinzia Tonetti, Diego Omar Sanchez Ramirez, Giorgio Mazzuchetti, Simona Ortelli, Magda Blosi, Anna Luisa Costa (41-48).
Few polymers with practical and technological appeal can be electrospun into nanofibers from water solutions.The production of polymer nanofibers from water solution is considered green, up-scalable and versatile. From this pointof view, the use of nanoparticles in the form of water colloidal suspension instead of nano-powder should be more affordableand safer. The combination of these two aspects makes a breakthrough in materials science on electrospun nanomaterials.In this work, multi-component organic/inorganic nanofibers were produced by electrospinning water solutionsof a protein extracted from wool (i.e. keratin) containing nanosols of titanium dioxide and metal silver. In order to improveelectrospinnability, poly(ethylene oxide) was added to the solutions. Colloidal stability was studied in depth to preservenanoparticle dimension as smaller as possible in the electrospinning solutions. Resulting hybrid keratin-based nanofiberswere made water insoluble by treatments at high temperature, expanding the range of applications of such a nanomaterial.In this way, it was also possible to wash out poly(ethylene oxide) from nanofibers maintaining a nanofibrousstructure and small-sized porosity comparable to the as-spun materials. Finally, the functional properties of electrospunhybrid nanofibers were evaluated. Both antibacterial and photo-catalytic activities of titanium dioxide nanoparticles embeddedinto the nanofibers were quantified, as well as antibacterial property of nano-silver. The results demonstrate thatnanoparticle functionalities were maintained in electrospun keratin nanofibers.

A Short Overview on Light Enhancement in SOI and Void Nanostructures by M. Ciobanu, D. Savastru, R. Savastru, A. Popescu, S. Miclos, M. Tautan, M.I. Rusu (49-55).
Photonics has experienced rapid growth in recent years and market promotion. Photonics is an emerging fieldof science which deals with nanoscale fabrication and characterization techniques. The aim of this paper is to overviewsome achievements on light harnessed in photonic nanostructures. We present the results from recent papers and fromseminal papers. Successful approaches from relevant literature, together with results from our own research are presented.Our research was performed by numerical integrations with the MIT codes and dealt especially with light confinement innanostructures. This progress has brought with it a renewed interest in surface plasmon-polaritons that allowelectromagnetic energy to be localized, confined, and guided on subwavelength scales. Moreover, the locally enhancedfield intensities observed in plasmonic structures promise potential for molecular biosensing, surface enhanced Ramanspectroscopy, and nonlinear optical device applications.

Optimization of the Preparation Condition of 2,4,5-triphenyl-1H-imidazole Over BaSO4 Nanoparticles as Catalyst Using a Response Surface Methodology (RSM) by Ali Behmaneshfar, Majid Ghashang, Mohammad Reza Mohammad Shafiee, Ali Saffar-Teluri, Abbas Fazlinia, Hadi Esfandiari (56-63).
A study on the application of Response Surface Methodology (RSM) for the optimization of the process parametersof the preparation of 2,4,5-triphenyl-1H-imidazole over BaSO4 nanoparticles as catalyst was explored. A threelevel,three-factor, Box-Behnken experimental design has been employed to determine the effects of process parametersnamely temperature (20-130 °C), catalyst dosage (0.01-0.5) and initial NH4OAc concentration (2-4 mmol). The secondorder mathematical model was developed by regression analysis of the experimental data obtained from 30 runs. Highestyield of product and lowest time of process were obtained at the optimum conditions as: temperature (130 °C), catalystdosage (0.5 mmol) and NH4OAc concentration (4 mmol).

Microbicidal Tissue Paper Using Green Synthesized Silver Nanoparticles by S.C.G. Kiruba Daniel, J. Abirami, S. Kumaran, M. Sivakumar (64-68).
Microbicidal tissue paper is made by a simple method of impregnating biosynthesized silver nanoparticles withthe conventional tissue paper. A number of infections are being transmitted by conventional tissue paper especiallythrough hospitals. Silver nanoparticles were synthesized by green synthetic route using the leaf extract of Eichornia crassipes,further characterized using UV Vis spectroscopy exhibiting a SPR peak at 413 nm and HRTEM having a size between20 to 50 nm. We have developed a hybrid tissue paper for control of spreading of hospital infections. The hybridtissue paper was characterized by X - Ray Diffraction and Field Emission Scanning Electron Microscopy in which thesize of the nanoparticles present in the tissue paper was found to be ranging from 20 nm to 50 nm. Antimicrobial activitywas evaluated against clinical pathogens - Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa and releasestudies of nanoparticles from the hybrid tissue paper were carried out to ascertain the antimicrobial nature.

Among all separation techniques, membrane technology has been shown to reduce CO2 emissions without anyphase changes due to its rapid, energy efficient process. The membrane-based gas separation must consist of a defect-free,thin, dense skin layer that is supported by a porous sub-layer that allows an excellent permeation rate and selectivity. Thisstudy is aimed at developing a defect-free, thin-skinned layer of mixed matrix membrane (MMM) from cellulose acetate(CA) polymer and functionalized multi walled carbon nanotubes (MWCNTs) as inorganic filler. The influences of membranecasting thickness (150-300) µ m and CA polymer concentration (7-17) wt.% on membrane morphologies were firstinvestigated. The outcome of these dominant parameters were then used to synthesize the MMM. The results showed thatthe defect-free, thin, dense skin thickness of membrane could be achieved with a casting thickness of 250 µ m and CApolymer concentration of 10 wt.%. By considering both dominant parameters, the synthesized MMM proved to have athin selective layer, whereby it showed a high permeance and selectivity for CO2/N2 gas separation.

Gold nanoparticles were synthesized, using a straightforward photoreduction protocol in the presence of mixedaddendaPreyssler heteropolyacid, H14[NaP5W29MoO110], (PMo). It acts as a reductive agent, as well as a photocatalystand stabilizing agent. The obtained results showed that the construction rate, morphology and the size of the goldnanoparticles strongly depend on the volume of propan-2-ol amount, used as solvent in the reaction. The shapes of thesynthesized gold nanoparticles in the low volume of the solvent were almost uniform spheres with the size of 40-60 nm.The morphologies of the gold nanoparticles in higher volume of the same solvent were found to involve a mixture of triangular,tubular, pentagonal and hexagonal structures along with spheres in range of 5-30 nm. Besides, the ability of thePMo as reductive agent for the syntheses of gold nanoparticles onto the surface of TiO2 via photochemical technique wasinvestigated. The results showed that, PMo as a reducing catalytic linker could be bound onto titanium dioxide for synthesesof the desired gold nanoparticles. The synthesized gold nanoparticles and nanocomposites were characterized byTEM, XRD, SEM, UV and FTIR techniques. The photocatalytic activity of the synthesized nanocomposite was measuredby photodegradation of the organic dye “malachite green” under UV-Vis light and was found to be excellent.

Analytical Study of Electronic Structure in Archimedean Type-Spiral Zig-Zag Graphene Nanoscroll by Afiq Hamzah, Mohammad Taghi Ahmadi, Razali Ismail (87-94).
The semiconducting electronic properties of graphene nanoscroll (GNS) are very much related to its geometricstructure. The aim of this study is to construct a GNS energy dispersion model within low-energy transport of 1 eV inidentifying its electronic properties and carrier statistics. Non-parabolic energy dispersion is used to incorporate the Archimedeantype-spiral model, and the band gap is assessed based on chirality and geometry effects. The energy bandwithin low-energy transport indicates that GNS can achieve a quantum conductance limit of ~ 6.45 kΩ for ballistic transport.On the other hand, the numbers for three minimum sub-bands are attained based on non-parabolic energy dispersion,and the semi-metallic zig-zag GNS is found at chirality (3j + 1, 0). This work consistently predicts the semiconductingproperties of the tight-binding model from previous work. The GNS overlapping region strongly affects its electronicproperties. Constantly increasing the length of the overlapping region decreases the band gap exponentially, whilst semimetallicGNS forms when the overlap reaches a certain limit. The carrier density with temperature dependence is subsequentlyassessed at the intrinsic level, and found that the number of carriers in GNS shows a higher rate of increment (exponentially)compared to carbon nanotubes (CNT), in accordance to their diameter. The results are very useful in givingan intuitive understanding on GNS carrier statistics as subject to geometry changes.

Growth of the Nano-islands of Barium Aluminum Oxide Nano-spheres on the Surface of Al2O3-MgO Composite: Preparation and Evaluation of their Catalytic Activity by Majid Ghashang, Saeid Jabbarzare, Hamed Tavakoli, Hamid Banisadeghi, Amir Hosein Sokhanvar, Mahmod Lotfi, Akbar Chami (95-100).
The islands like barium aluminum oxide BaAl2O4 nano-spheres were grown on the surface of Al2O3-MgOcomposite via oil in water (O/W) micro-emulsion method. Hexane, 2-aminoethanol and ethanol were used as oil phase,non-anionic surfactant and co-surfactant respectively. The synthesized Ba Al2O4 nano-spheres were grown on the surfaceof Al2O3-MgO composite and have been characterized using X-ray diffraction (XRD), field emission scanning electronmicroscopy (FE-SEM) and Energy-dispersive X-ray spectroscopy (EDAX). The BaAl2O4 nano-spheres grown on the surfaceof Al2O3-MgO composite exhibited high catalytic activity for the transformation of cinnamaldehyde, methyl/ethylacetoacetate and aromatic amines as the starting materials to 1,4-dihydropyridine derivatives.

A modified sol-gel method was applied to prepare 0.3%La-3%In-TiO2 in order to investigate the effect of calcinationtemperature. The material was investigated by SEM, XRD, and N2 adsorption-desorption methods. The diffractionpeaks of the sample are in accordance to the patterns of anatase TiO2. The anatase crystallite sizes are 5.5, 6.3, 11.1,and 15.6 nm for the samples calcinated at 350°C, 400°C, 500°C, and 600°C, respectively. Crystal cell expansion is foundwhen calcination temperature increases from 350°C to 500°C. The increase of average pore size and decrease of pore volumewith increasing calcination temperature are found for 0.3%La-3%In-TiO2. The 0.3%La-3%In-TiO2 calcinated at400°C has satisfactory adsorption capacity and photocatalytic activity. 25.6% of the initial methyl orange can be adsorbedon the material after adsorption-desorption equilibrium. After that, the remaining methyl orange can be fully degraded after40 min of irradiation.

Effect of Morphology of Co3O4 for Oxygen Evolution Reaction in Alkaline Water Electrolysis by Qi-Zhi Xu, Yu-Zhi Su, Hao Wu, Hui Cheng, Yun-Ping Guo, Nan Li, Zhao-Qing Liu (107-112).
In this paper, three different morphological Co3O4 electrodes for oxygen evolution reaction (OER) have beensynthesized. By comparing the three morphologies of Co3O4, the electrocatalytic properties show that the urchin-likespheres of Co3O4 electrode has relative low overpotential and good electrocatalysis stability, indicating that the structureof urchin-like Co3O4 spheres exhibit an easy OER for water splitting.

Impacts of Amine Functionalized Iron Oxide Nanoparticles on HepG2 Cell Line by Alireza Ebrahiminezhad, Sara Rasoul-Amini, Amin Kouhpayeh, Soodabeh Davaran, Jaleh Barar, Younes Ghasemi (113-119).
Iron oxide nanoparticles (IONs) are being used in medicine for magnetic resonance imaging, drug delivery andhyperthermia. There are contradictory data about cytotoxic effects of IONs on various cell lines. In this study a couple ofIONs with two biocompatible coatings, L-lysine and 3-aminopropyltriethoxysilane, were synthesized by coprecipitationmethod in aqueous matrix and characterized. The MTT assay was used to evaluate the effects of the synthesised IONs onHepG2 cells. Cell culture illustrated that the growth of HepG2 cells can be promoted by IONs and nanoparticles with biocompatiblecoating have more biological benefit impacts than naked particles. By increase in concentration, cytotoxic effectswill appear and reduce the growth promotion effects. Cytotoxic effects are in relation with agglomeration degree ofnanoparticles, agglomeration can reduce cytotoxicity of IONs at high concentrations.

A New Type of Super Hydrophilic SiO2 Aerogel for Use as a Potential NH3 Sorbent by Benlan Lin, Juqi Ruan, Sheng Cui, Xiaodong Shen, Shuwen Yu (120-128).
A super hydrophilic SiO2 aerogel (SHSA) was prepared using the sol-gel method and CO2 supercritical dryingtechnology, yielding a specific surface area of 680.08 m2/g and a total pore volume of 3.95 cm3/g. The hydrophilic propertyof the SHSA was investigated and showed a maximum water adsorption capacity (qm) of 7.79 ml/g. NH3 adsorptiontests were conducted and were compared with the results for pure SiO2 aerogel (PSA) under non-water vapor and watervapor treating conditions. The effect of water vapor on SHSA was found to be larger than its effect on PSA. A physicalchemicaladsorption process of NH3 appeared in the presence of water vapor on the SHSA surface, giving a maximum adsorptioncapacity (Qm) of 193.66 mg/g. The regenerability of SHSA was also investigated, and the loss percentage of Qmwas found to be 22.28% over 10-cycle adsorption tests. The results indicate that SHSA is a promising candidate for use asan NH3 sorbent.

Synthesis and Immobilization of MnO2 Nanoparticles on Bio-silica for the Efficient Degradation of an Azo Dye in the Aqueous Solution by Alireza Khataee, Soghra Bozorg, Behrouz Vahid, Trung-Dung Dang, Younes Hanifehpour, Sang Woo Joo (129-134).
In this study, MnO2 nanoparticles were synthesized on bio-silica by a simple one-step procedure using permanganatein the acidic medium. The synthesized catalyst was characterized by X-ray diffraction (XRD), scanning electronmicroscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR). The obtained results confirmed the nanostructureof MnO2 and its stabilization on the bio-silica as the support. The removal efficiency of acid orange 7 (AO7), usingbare bio-silica and MnO2 coated bio-silica, was found to be 5 and 95%, respectively. The effect of operational parametersincluding AO7 concentration, catalyst dosage and process time of treatment process was also studied on the basis of efficiency.The results demonstrated that the color removal efficiency was decreased by increasing AO7 concentration, andincreased by the enhancement of the process time. The optimal dosage of 0.8 g/L was chosen for the catalyst amount. Hydroxylradicals played a significant role in the process based on the proposed mechanism. The spectral changes of AO7during the process in UV-Vis region showed not only the efficient decolorization, but also the degradation of the dye after50 min of the treatment.

Superior Cell Adhesion and Antithrombogenicity Supported by N+-bombarded Carbon Nanotubes by M.L. Zhao, X.Q. Liu, Y. Cao, D.J. Li, H.Q. Gu (135-142).
Super hydrophilic multi-walled carbon nanotubes (MWCNTs) were bombarded by N ions through ion beamassisted deposition. MWCNTs were synthesized via chemical vapor deposition. Biological tests in vitro were performedon raw MWCNTs and N+-bombarded MWCNTs. Cellular adhesion was investigated both using human endothelial cellsand mouse fibroblast cells. Results showed that N+-bombarded MWCNTs stimulated cell growth and proliferation, revealing superior cell adhesion. Antithrombogenicity of raw and N+-bombarded MWCNTs was evaluated by platelet conglutination, hemolysis and kinetic-clotting assays. Compared with raw MWCNTs, N+-bombarded MWCNTs displayed better morphology of platelets and red blood cells, longer kinetic blood-clotting time, which increased their thromboresistance, further antithrombogenicity.