研究者詳細 - 安藤　義人

論文 - 安藤　義人

分割表示185 件中 61 - 80 件目／全件表示 >>

Designing Approach of Fiber-Reinforced Polymer Composite by Combination of Fibrillated Olive Pomace and Marble Powder 査読有り国際誌

Tessei Kawano, Gamze Dinç, Esra Yel, Yoshito Andou

Macromolecular Materials and Engineering 2022年11月

Recent Progress in Photocatalytic Efficiency of Hybrid Three-Dimensional (3D) Graphene Architectures for Pollution Remediation 査読有り

3. Zheng A.L.T., Ohno T., *Andou Y.

Topics in Catalysis 2022年04月

Facile Preparation of Cellulose Fiber Reinforced Polypropylene Using Hybrid Filler Method 査読有り国際誌

Mustapha S., Lease J., Eksiler K., Sim S.T., Ariffin H., Andou Y.

Polymers ( MDPI AG ) 14 ( 8 ) 1630 2022年04月

担当区分：最終著者記述言語：英語掲載種別：研究論文（学術雑誌）

Dried hybrid fillers comprised of silica/CNF were successfully synthesized in ethanol/water mixed solvents at room temperature without the usage of any precursor. The as-prepared fillers were incorporated with polypropylene (PP) as a polymer matrix through a twin-screw extruder. From surface morphology analysis, the agglomeration of the silica/CNF hybrid fillers was prevented in the PP matrix and they exhibited moderate transparency, around 17.9% and 44.6% T at 660 nm. Further, the chemical structures of the polymer composites were identified by Fourier transform infrared (FT-IR) analysis. According to thermogravimetric analysis (TGA), the insertion of silica as a co-filler to the PP matrix resulted in an increase in its degradation onset temperature and also thermal stability. In addition, the mechanical properties of the PP composites also increased after the blending process with the hybrid fillers. Overall, sample PP-SS/CNF exhibited the highest tensile strength, which was 36.8 MPa, or around 73.55% compared to the pristine PP. The improvements in tensile strength were attributed to good dispersion and enhanced efficiency of the stress transfer mechanism between the silica and the cellulose within the PP matrix. However, elongation of the sample was reduced sharply due to the stiffening effect of the filler.

DOI： 10.3390/polym14081630

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Cadmium(II) and copper(II) complexes containing benzoate derivatives and 2-aminopyrimidine ligands: Synthesis, crystal structures and antibacterial activity 査読有り国際誌

Thummatudtho S., Phadungsak N., Chainok K., Kandiah M., Zheng A.L.T., Andou Y., Boonyuen S.

Journal of Physics: Conference Series 2175 ( 1 ) 2022年02月

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

The new Cd(II) and Cu(II) complexes namely [Cd2(2-OHbza)4(apm)4] (1), [Cu2(2-OHbza)4(apm)]n•2(2-OHbza) (2) and [Cu2(2-CH3bza)4(apm)]n (3) (2-OHbza = 2-hydroxybenzoate, 2-CH3bza = 2-methylbenzoate and apm = 2-aminopyrimidine) were successfully prepared by using direct one pot synthesis method. All complexes were characterized by using CHN elemental analysis, FT-IR spectroscopy, powder X-ray diffraction and single crystal X-ray diffraction techniques. Compound 1 crystallized in monoclinic space group P21/c, while compound 2 and 3 crystallized in triclinic space group P-1. The dinuclear compound 1 consists of two seven-coordinated Cd(II) centers which are doubly bridged by 2-OHbza bridging ligands, while the rest two 2-OHbza and two apm are terminal ligand. The crystal structure of compound 1 is stabilized by the intermolecular hydrogen bonding and C-H•••pinteraction and p•••pinteractions. Compounds 2 and 3 present zigzag one-dimensional chainlike-structure which dimer Cu(II) units are linked by apm ligand. The crystal structure of these compounds is stabilized by p•••pand C-H•••pinteractions. The photoluminescence properties of compound 1 has been studied comparing to those of 2-OHbza and apm ligands. The solid state PL emission spectrum of compound 1 shows similar intensity of free apm ligand and shape to free 2-OHbza ligand which present a single broad band centered at ?em 525 nm (?ex = 325 nm), but blue-shift. For solution PL experiment of compound 1 in various solvents, the results showed that compound 1 is selective PL quenching acetone. Electronic spectra for solid state and solution in different solvents of compounds 2 and 3 present the d-d absorption bands centered in the range of 701 - 794 nm. The highest red shifts of ?max are found for compounds 2 and 3 in DMSO. In addition, the antibacterial activity of all compounds are investigated for S.aureus and E.coil by agar diffusion method. The results show that compound 1 exhibits the activity against S.aureus better than E.coil.

DOI： 10.1088/1742-6596/2175/1/012024

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Biodiesel production from used palm oil using magnetic solid base catalyst 査読有り国際誌

Singhanatkaisi N., Kandiah M., Zheng A.L.T., Ando Y., Boonyuen S.

Journal of Physics: Conference Series 2175 ( 1 ) 2022年02月

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

In this research the biodiesel from palm oil were synthesized by using magnetic solid base catalyst. The magnetic solid base catalyst was prepared by using co-precipitation method and followed by modified Stober's method and wet impregnation method. CaO-ferrite nanometre magnetic solid base catalysts (CaO@Fe3O4/SiO2) were synthesized by loading CaO on the surface of Fe3O4 core-shell using the polymeric binder, TEOS. Under the optimized condition reactions, the catalysts were synthesized by co-precipitation and incipient wetness impregnation followed by calcination at 700 °C for 5 h. The calcined catalyst was fully characterized. The basic strength of the catalysts (H_) was first assessed using Hammett indicators, which are in range 9.8-15.0. The calcined Ca/ferrite-TEOS showed homogenous spherical shape with an apparent thickness of 92 nm. The FT-IR of CaO observed at 520 cm-1 is attributed to the Ca-O vibrations. The EDX analysis confirmed the presence of Fe, Si and Ca on the catalyst. The optimization conditions for biodiesel production have been measured. The catalyst was used 5.0 % wt. The methanol to oil ratio is 5:1, reaction time is 180 minutes and reaction was produced at 80°C. The catalyst achieved a biodiesel conversion of used palm oil (acid value 1.2) above 92 %. The catalytic activity and recovery rate of CaO@Fe3O4/SiO2 are better as compared to CaO catalyst. The properties of synthesized biodiesel have been studied and meet standard the Department of Energy Business.

DOI： 10.1088/1742-6596/2175/1/012025

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Recent Progress in Photocatalytic Efficiency of Hybrid Three-Dimensional (3D) Graphene Architectures for Pollution Remediation 査読有り国際誌

Zheng A.L.T., Ohno T., Andou Y.

Topics in Catalysis 65 ( 19-20 ) 1634 - 1647 2022年01月

担当区分：最終著者,　責任著者記述言語：英語掲載種別：研究論文（学術雑誌）

The importance of pollutant remediation using solar energy is increasingly acknowledged as a viable method to solve the current environmental problems. To date, three-dimensional (3D) graphene architectures have demonstrated excellent photocatalytic performance due to their salient characteristics. The hydrothermal treatment is the commonly reported synthetic protocol in preparing various novel hybrid 3D graphene architectures. This chapter focuses on the recent progress in developing and applying hybrid 3D graphene for the photocatalytic remediation of organic pollutants such as dye molecules, emerging contaminants, and heavy metals. Various novel design based on semiconductor/3D graphene has led to the creation of highly efficient heterojunction photocatalyst. The transformation to a 3D architecture does not only improve the accessible surface area but also enhanced light harvesting capability and charge transport. In addition, we have also made an effort to discuss some photocatalytic antibacterial disinfection innovations. Finally, prospects in the construction of hybrid 3D graphene possessing enhanced photocatalytic materials are presented. Graphical Abstract: [Figure not available: see fulltext.].

DOI： 10.1007/s11244-022-01610-9

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Recent progress in visible light-doped ZnO photocatalyst for pollution control 査読有り国際誌

Zheng A.L.T., Abdullah C.A.C., Chung E.L.T., Andou Y.

International Journal of Environmental Science and Technology 20 ( 5 ) 5753 - 5772 2022年01月

担当区分：最終著者,　責任著者記述言語：英語掲載種別：記事・総説・解説・論説等（学術雑誌）

The design and development of visible light photocatalysts for wastewater remediation applications have received considerable attention due to their ability to operate under low energy, renewable and clean. The application of ZnO nanostructures as a photocatalyst in various photodegradation applications has shown to be of continued interest. However, ZnO possessed several setbacks, including their large bandgap, which require high energy for the excitation of the electrons. To overcome these limitations, doping ZnO photocatalysts has been confirmed to enhance their photocatalytic performance by narrowing their large bandgap, thus opening up numerous possibilities. Doped ZnO nanostructures have found extensive use in pollution control applications as visible light photocatalysts. The doping with metal or non-metal elements, metal oxides, and inclusion with other semiconductors to form a hybrid heterojunction photocatalyst are among the strategies employed. This mini review summarizes recent progress in the strategies employed in the preparation of doped ZnO photocatalysts for the degradation of various organic pollutants, including synthetic dye molecules and emerging contaminants. Their application in antibacterial performance is also briefly explained. Additionally, the degradation mechanism of selected pollutants is also discussed. Finally, the advantages of using doped ZnO photocatalyst for pollution remediation are discussed. Considering the issue of water security, this review is timely to address the impending problem that the world is facing. Hopefully, this article can assist readers in gaining a better understanding of doped ZnO photocatalysts.

DOI： 10.1007/s13762-022-04354-x

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High lead ion removal in a single synthetic solution utilising plant-based Tacca leontopetaloides biopolymer flocculant (TBPF) 査読有り国際誌

Mohd Makhtar N.S., Idris J., Musa M., Andou Y., Ku Hamid K.H., Puasa S.W.

Process Safety and Environmental Protection 165 977 - 986 2022年01月

記述言語：英語掲載種別：研究論文（学術雑誌）

The present study aimed to remove lead ions (Pb2+) in a single synthetic solution by employing a plant-based Tacca leontopetaloides biopolymer flocculant (TBPF). The ions were eliminated through the flocculation process via the Jar test experiment. The maximum Pb2+ removal was determined based on one-factor-at-a-time (OFAT) and central composite design (CCD). Based on the OFAT, the maximum Pb2+ eliminated, 83%, was achieved at pH 6 synthetic solution, 2.5 mg/L initial Pb2+ concentration, and 3% initial TBPF concentration at 192 mg/L dosage. The highest Pb2+ removal of 73% was recorded at pH 6.4 synthetic solution with 11.8 mg/L initial Pb2+ concentration at a constant 3% initial TBPF concentration and 192 mg/L TBPF dosage when the CCD was employed. The excellent Pb2+ removal with the environmentally friendly plant-based TBPF utilised in the current study demonstrated outstanding potential in industrial heavy metal treatments, particularly at the primary stages.

DOI： 10.1016/j.psep.2022.05.047

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Designing Approach of Fiber-Reinforced Polymer Composite by Combination of Fibrillated Olive Pomace and Marble Powder 査読有り国際誌

Kawano T., Dinç G., Yel E., Andou Y.

Macromolecular Materials and Engineering 308 ( 5 ) 2022年01月

担当区分：最終著者,　責任著者記述言語：英語掲載種別：研究論文（学術雑誌）

The development of effective methods to utilize industrial and agricultural wastes is crucial from the perspective of a circular economy. Marble powder and olive pomace (OP), byproducts of olive oil production and marble processing, are considered one of the major sources causing severe environmental pollution, especially in Mediterranean countries. Herein, marble powder and OP are aimed to use as fillers in polypropylene (PP)-based polymer composite. In addition, fractionated OP is further fibrillated by a combination of mechanical grinding and ionic liquid treatment to enhance its performance as a reinforcement. After treatment for 24 h, the particle size decreases from about 2.1 to 1.1 µm, and the lignocellulosic composition also varies due to the partial removal of hemicellulose. Finally, the compounding ratio of polymer composites consisting of PP, marble powder, fibrillated OP, and compatibilizer is optimized using response surface methodology (RSM) to achieve both high mechanical properties and high filler contents. Mechanical properties of polymer composite fabricated with optimum ratio are in excellent agreement with those predicted by RSM. Furthermore, the yield strength and Young's modulus of polymer composite are 33.9 MPa and 1.89 GPa, accordingly, which are higher than those of PP.

DOI： 10.1002/mame.202200588

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Cu2O/TiO2 decorated on cellulose nanofiber/reduced graphene hydrogel for enhanced photocatalytic activity and its antibacterial applications 査読有り

Zheng, Alvin Lim Teik a; Sabidi, Sarah a; Ohno, Teruhisa b; Maeda, Toshinari a, c; Andou, Yoshito a

Chemosphere 286 2022年01月

Design of reduced graphene hydrogel with alkylamine surface functionalization through immersion/agitation method and its adsorption mechanism 査読有り国際誌

Zheng A.L.T., Boonyuen S., Li G.Y., Ngee L.H., Andou Y.

Journal of Molecular Structure 1245 2021年12月

担当区分：責任著者記述言語：英語掲載種別：研究論文（学術雑誌）

To date, existing methods for graphene functionalization entail complex procedures, hence efficient and facile methods are desired. In this study, alkylamine functionalization on reduced graphene hydrogel (rGH) was achieved via a facile two-step method involving hydrothermal treatment of graphene oxide (GO) to rGH followed by the immersion/agitation treatment of the rGH in octylamine (OA), decylamine (DA) and dodecylamine (DDA). It was found that the interactions of the alkylamine occurred via the epoxy ring-opening and amidation. To emphasize the advantage of this method, the adsorption kinetics on methylene blue (MB) and bisphenol-A (BPA) was further accessed. Shorter alkyl chain alkylamine (OA & DA) functionalized rGHs showed improvement in their adsorption capacity due to the increase in the specific surface area of the hydrogels. The highest specific surface area was obtained for rGH-DA at 47.80 m2/g followed by rGH-OA (47.37 m2/g), rGH-DDA (42.00 m2/g) and rGH (27.29 m2/g). However, longer chain alkyl chain alkylamine (DDA) functionalized rGHs showed lower adsorption capacity posited from the crowding of long alkyl chain which decreases the π–π interactions between the MB/BPA and the graphene sheets. rGH-DA exhibited the highest adsorption capacity for MB and BPA at 482 and 228 mg/g, respectively. In addition, the alkylamine functionalized hydrogels showed high regeneration behaviour after three cycles of adsorption-desorption: above 85% and 75% for MB and BPA, respectively. This proposed facile functionalization route will open interesting possibilities in the design of novel reduced graphene-based based hydrogels with improved adsorption performance that can bring ample benefits in wastewater remediation.

DOI： 10.1016/j.molstruc.2021.131008

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Accessing the anti-microbial activity of cyclic peptide immobilized on reduced graphene oxide 査読有り国際誌

Zheng A.L.T., Farrag H.N., Sabidi S., Kato T., Maeda T., Andou Y.

Materials Letters ( Elsevier BV ) 304 130621 2021年12月

担当区分：最終著者,　責任著者記述言語：英語掲載種別：研究論文（学術雑誌）

Herein, we prepared and characterized two antimicrobial cyclic peptides immobilized on reduced graphene oxide (rGO) and accessed their anti-bacterial towards Gram-negative (Pseudomonas aeruginosa) and Gram-positive (Staphylococcus aureus) bacterias. The covalent interaction between the tyrosine and histidine based cyclic peptides and the rGO occurred via the carboxylic groups of the reduced graphene and the amino side chain groups of the cyclic peptides. A selective antibacterial effect is observed for the cyclic peptides functionalized rGO. The inhibition zone test showed that both the tyrosine and histidine cyclic based peptide immobilized on rGO exhibited higher anti-bacterial potency towards the bacteria in comparison to bare rGO which can be attributed to the synergistic effect of the antimicrobial peptide and rGO.

DOI： 10.1016/j.matlet.2021.130621

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The relationship between crystal structure and mechanical performance for fabrication of regenerated cellulose film through coagulation conditions 査読有り国際誌

Kawano T., Iikubo S., Andou Y.

Polymers ( MDPI AG ) 13 ( 24 ) 4450 2021年12月

担当区分：責任著者記述言語：英語掲載種別：研究論文（学術雑誌）

Cellulose films regenerated from aqueous alkali–urea solution possess different properties depending on coagulation conditions. However, the correlation between coagulant species and properties of regenerated cellulose (RC) films has not been clarified yet. In this study, RC films were prepared from cellulose nanofiber (CNF) and microcrystalline cellulose (MCC) under several coagulation conditions. Cellulose dissolved in aqueous LiOH–urea solution was regenerated using various solvents at ambient temperature to investigate the effects of their dielectric constant on the properties of RC film. The crystal structure, mechanical properties, and surface morphology of prepared RC films were analyzed using X-ray diffraction (XRD), tensile tester, and atomic probe microscopy (AFM), respectively. It is revealed that the preferential orientation of (110) and (020) crystal planes, which are formed by inter-and intramolecular hydrogen bonding in cellulose crystal regions, changed depending on coagulant species. Furthermore, we found out that tensile strength, elongation at break, and crystal structure properties of RC films strongly correlate to the dielectric constant of solvents used for the coagulation process. This work, therefore, would be able to provide an indicator to control the mechanical performance of RC film depending on its application and to develop detailed researches on controlling the crystal structure of cellulose.

DOI： 10.3390/polym13244450

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Esterification of cellulose with long fatty acid chain through mechanochemical method 査読有り国際誌

Lease J., Kawano T., Andou Y.

Polymers ( MDPI AG ) 13 ( 24 ) 4397 2021年12月

担当区分：責任著者記述言語：英語掲載種別：研究論文（学術雑誌）

Mechanochemical reaction, a green synthetic esterification route was utilized to prepare long-chain cellulose esters from microcrystalline cellulose. The influence of reaction conditions such as reaction temperature and time were elucidated. Only low dosage of oleic acid, 1-butyl-3-metylimidazolium acetate, and p-toluenesulfonyl chloride were required. The success of modification reaction was confirmed by Fourier transforms infrared spectroscopy as a new absorbance peak at 1731 cm−1 was observed, which indicated the formation of carbonyl group (C=O). Solid-state nuclear magnetic resonance was also performed to determine the structural property and degree of substitution (DS) of the cellulose oleate. Based on the results, increasing reaction temperature and reaction time promoted the esterification reaction and DS. DS values of cellulose oleates slightly decreased after 12 h reaction time. Besides, X-ray diffraction analysis showed the broadening of the diffraction peaks and thermal stability decreased after esterification. Hence, the findings suggested that grafting of oleic acid’s aliphatic chain onto the cellulose backbone lowered the crystallinity and thermal stability.

DOI： 10.3390/polym13244397

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Highly sensitive organic phototransistors fabricated from PCPDTBT: PCBM blend 査読有り国際誌

Yadav N., Kumari N., Ando Y., Pandey S.S., Singh V.

Journal of Physics: Conference Series 2070 ( 1 ) 2021年11月

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

Organic phototransistors (OPTs) play a crucial role in various light sensing and imaging applications. In this work, we have fabricated highly sensitive Poly[2,6-(4,4-bis-(2ethylhexyl)-4H-cyclopenta[2,1-b;3,4-b']dithiophene)-alt-4,7(2,1,3-benzothiadiazole)] (PCPDTBT)/[6,6]-phenyl-C61-butyric acid methyl ester (PCBM) blended thin film based OPTs using ribbon-floating film transfer method. A high charge carrier mobility (µ) of 0.002 cm2V-1s-1 and an Ion/Ioff of 6 × 104 was showcased by the blended polymer thin film based OPT as compared to its pristine polymer thin film based counterpart which had a µ of 0.001 cm2V-1s-1 and an Ion/Ioff of 9 × 103. Further, the blended polymer thin film based OPT demonstrated a high photosensitivity of 6.6 × 103 and a photoresponsivity of 0.13 A/W towards white light which were much superior than those of many of the previously reported polymer thin film based OPTs. The results hold crucial significance towards the development of cost effective blended polymer thin film based OPTs.

DOI： 10.1088/1742-6596/2070/1/012040

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Tunable electrochemical behavior of dicarboxylic acids anchored Co-MOF: Sensitive determination of rutin in pharmaceutical samples 査読有り国際誌

Sivam T., Gowthaman N.S.K., Lim H.N., Andou Y., Arul P., Narayanamoorthi E., John S.A.

Colloids and Surfaces A: Physicochemical and Engineering Aspects ( Elsevier BV ) 622 126667 2021年08月

記述言語：英語掲載種別：研究論文（学術雑誌）

Rutin (RT) also known as vitamin P, is an electroactive flavanoid mainly found in plants. It is generally applied as a clinical drug, Chinese traditional medicine and consumed as a supplement and act as a healthy collagen. Consumption of RT as supplement associated with some side effects and certain people has allergy towards RT. Therefore, it is meaningful to develop a fast, simple and reliable method to detect RT to avoid health risks. This paper describes the facile synthesis of Co-MOF using 1,4-benzenedicarboxylic acid (BDC) and biphenyl-4,4-dicarboxylic acid (BPDC) as ligands through solvothermal method. The XRD patterns and FT-IR spectra confirm the formation of Co-BDC and Co-BPDC MOFs. Moreover, the SEM images revealed that the Co-BDC MOF possesses a stacked layer of MOF while Co-BPDC MOF shows a flower-like MOF. The Co-BDC and Co-BPDC MOFs were fabricated on GC electrode for the sensitive determination of RT. The ligands with different chain lengths in the MOFs have influenced the interaction of RT with the MOF. The Co-BPDC-MOF/GCE exhibited an excellent electrocatalytic activity than the Co-BDC-MOF/GCE and the fabricated electrode was successfully utilized for the determination of RT in pharmaceutical samples. The fabricated sensor exhibited the limit of detection of 0.03 µM (S/N = 3) and the superior sensitivity of 781.43 µA/mM/cm2 in the linear range detection of 0.5 – 1000 µM RT with excellent repeatability, reproducibility, and good anti-interference ability.

DOI： 10.1016/j.colsurfa.2021.126667

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Accessing effects of aliphatic dicarboxylic acid towards the physical and chemical changes in low temperature hydrothermally reduced graphene hydrogel 査読有り

Zheng A.L.T., Boonyuen S., Ohno T., Andou Y.

Journal of Porous Materials 28 ( 4 ) 1291 - 1300 2021年08月

担当区分：責任著者記述言語：英語掲載種別：研究論文（学術雑誌）

To date, studies pertaining the usage of aliphatic dicarboxylic acids (DCAs) in the preparation of graphene-based hydrogels are limited and mainly has been applied either as a reducing agent or cross-linkers. The modification of the hydrogels' properties can be achieved via the introduction of small amount of additive into the starting material, graphene oxide (GO). The facile synthetic protocol enables the impartation of desired properties to the graphene-based hydrogel as intended for their specific applications. In this study, the in-situ preparation of reduced graphene hydrogel (rGH) was carried out in the presence of a series of aliphatic DCAs namely oxalic acid (OA), malonic acid (MA), succinic acid (SA), glutaric acid (GA) and adipic acid (AA) in the GO reaction mixture via green hydrothermal method and freeze-drying. The as-prepared hydrogels were systematically characterized to probe the changes in their chemical and physical changes. Higher specific surface (SSA) of the hydrogel is obtained for shorter chain length DCAs. The FTIR and XPS results also indicated that shorter chain DCAs exhibited better reducing capability in the removal of oxygen functional groups. The C/O ratio obtained showed decrement with the increase in the chain length of the DCA. On the other hand, good dispersity was found for longer chain DCAs in polar solvent. Overall, this study should provide a comprehensive understanding on hydrothermally reduced graphene hydrogels prepared in the presence of dicarboxylic acids.

DOI： 10.1007/s10934-021-01072-6

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Probing the metal/conducting polymer interface and implications of the metal diffusion in two-terminal sandwich devices 査読有り

Yadav N., Kumari N., Ando Y., Pandey S.S., Singh V.

Synthetic Metals 278 2021年08月

記述言語：英語掲載種別：研究論文（学術雑誌）

In this article, we have investigated the role of polymer regio-regularity and film fabrication technique in reducing metal diffusion from top electrodes in sandwich type devices. Poly(3-hexyl thiophene)(P3HT) polymer of varying regio-regularity was chosen for investigation and its corresponding thin films were fabricated by spin-coating(SC) and floating film transfer method(FTM). Sandwich devices with a top interface between gold and i) FTM coated regio-regular (rr) P3HT, ii) FTM coated non-regiocontrolled (nr) P3HT, iii) SC nr-P3HT and iv) SC rr-P3HT were fabricated. The current density vs voltage (J-V) characteristics of the devices revealed non-ohmic characteristics. Estimation of interfacial hole barrier heights using Fowler Nordheim tunneling model revealed a small barrier of 1.12 eV for the isotropic spin-coated nr-P3HT film which increased to 1.37 eV with an increase in film anisotropy for the FTM nr-P3HT film. The barrier height also gradually declined from 1.37 eV to 1.05 eV with increase in regioregularity from FTM nr-P3HT to FTM rr-P3HT. These observations were confirmed through optical and structural characterizations along with depth profiling of metal diffusion using XPS. Pronounced Au diffusion to a higher depth was observed in the XPS results for the highly anisotropic FTM film that decreased subsequently with decrease in anisotropy from FTM to spin-coated film. It was thus deduced that a judicious selection of fabrication technique and polymer aids in reducing metal diffusion leading to improved device performance. The results hold crucial significance towards the fabrication of efficient organic photodetectors that have a sandwich type device architecture.

DOI： 10.1016/j.synthmet.2021.116797

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Detection and remediation of bisphenol A (BPA) using graphene-based materials: mini-review 査読有り国際誌

安藤　義人

International Journal of Environmental Science and Technology 2021年07月

Development of High-Sensitivity Poly(2,7-(9,9-dioctylfluorene)-alt-5,5-(4′,7′-di-2-thienylbenzo [c][1,2,5]thiadiazole)) Thin-Film-Based Phototransistors by the Ribbon-Floating Film Transfer Method 査読有り

Nidhi Yadav, Nikita Kumari, Yoshito Ando, Shyam S. Pandey, and Vipul Singh

Physica Status Solidi - Rapid Research Letters 2021 2021年05月

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