Faculty Profiles - PANDEY Shyam sudhir

Papers - PANDEY Shyam sudhir

Division display41 - 60 of about 275／ All the affair displays >>

Optimization of Device Parameters for Back Contact Transparent Conductive Oxide Less Dye Sensitized Solar Cells Fabrication Reviewed International journal

Md Zaman Molla, Ajay Kumar Baranwal, Shuzi Hayase, Shyam S. Pandey

Physica Status Solidi-A ( Wiley ) 220 ( 4 ) 2300095(1) - 2300095(7) 2023.06

Authorship：Last author Language：English Publishing type：Research paper (scientific journal)

Transparent conductive oxide–less (TCO-less) dye-sensitized solar cell (DSSC) has been constructed and characterized employing mesoporous TiO2-coated stainless-steel mesh (S-S-mesh or Mesh) as a bendable photoanode and iodine-based redox electrolyte. Efforts have been directed toward optimizing electronic parameters to enhance the power conversion efficiency (PCE) of TCO-less DSSC to equalize its TCO-based DSSC counterpart. It is found that protection of Mesh is essential for increasing the PCE of TCO-less DSSCs employing iodine electrolyte as assured by suppressed reverse saturation current and better diode factor. The PCE of 5.6% is obtained with TCO-less DSSC compared with TCO-based DSSC with PCE of 6.09%. A bit of decrease in PCE with TCO-less DSSC is due to larger resistance in TiO2/dye/electrolyte as well as within electrolyte as evident by electrochemical impedance spectroscopy (EIS) study owing to the Mesh having perforated holes and larger thickness of electrolyte absorbing sheet of the porous polytetrafluoroethylene film (35 μm) compared to TCO-based DSSC without any barriers and lower electrolyte layer thickness of 25 μm.

DOI： https://doi.org/10.1002/pssa.202300095

Design and Synthesis of Novel Squaraine Dye with Highly Enhanced Far‐Red Fluorescence and its Interaction with a Model Protein Reviewed International journal

Shekhar Gupta, Yuki Yamawaki, Safalmani Pradhan, Shyam S. Pandey, Tamaki Kato

Physica Status Solidi-A ( Wiley ) 220 ( 24 ) 2300226(1) - 2300226(8) 2023.06

Language：English Publishing type：Research paper (scientific journal)

Novel amine-functionalized symmetrical squaraine (SQ)-dye and fluorescein isothiocyanate (FITC)–SQ–FITC dye conjugate are designed and successfully synthesized, followed by their structural and photophysical characterizations. Symmetrical SQ dye exhibits complete fluorescence quenching in polar solvents, which is explained by considering photoinduced electron transfer (PET) as a dominant quenching pathway. In contrast, FITC–SQ–FITC dye conjugate results in a decrease in an aggregation of both SQ and FITC units and about 47 times enhancement in the far-red fluorescence appearing at 674 nm. This profound enhancement in the far-red fluorescence is explained by the synergistic influence of suppression of aggregation-induced quenching (ACQ) and PET. This newly designed FITC–SQ–FITC dye conjugate shows complete quenching of the far-red fluorescence in phosphate buffer saline (PBS) owing to very strong dye aggregation, as confirmed by spectral absorption investigation. In PBS, it strongly interacts with bovine serum albumin (BSA) (Ka = 1.1 × 104 m−1) used as a model protein breaking the dye aggregation by BSA and increasing far-red fluorescence associated with SQ as a function of increasing BSA concentration. A profound 117 times increase in fluorescence at 674 nm with 25 times of BSA concentration suggests that the designed FITC–SQ–FITC is an excellent far-red probe for dye-protein interaction.

DOI： https://doi.org/10.1002/pssa.202300226

Other Link： https://onlinelibrary.wiley.com/doi/10.1002/pssa.202300226

Bistable Resistive Memory Switches Fabricated by Floating Thin Films of Conjugated Polymers Reviewed International journal

Shubham Sharma, Nikita Kumari, Shuichi Nagamatsu, Masakazu Nakamura, Shyam S Pandey

Materials Today Electronics ( Elsevier ) 4 100043(1) - 100043(1) 2023.06

Authorship：Last author,　Corresponding author Language：English Publishing type：Research paper (scientific journal)

The layer-by-layer (LBL) fabrication of conjugated polymer (CPs) thin films while preserving their microstructural features by solution processing is highly desired for compact and flexible electronic circuits. However, it is cumbersome and challenging owing to the unavoidable damage to the underlying layers. To circumvent this issue, the unidirectional floating-film transfer method (UFTM) was utilized for the LBL fabrication of oriented CP thin films on the orthogonal liquid surfaces. Further, resistive bistable memory switches were fabricated by sandwiching a layer of metal nanostructures between the LBL-fabricated oriented CP thin films. The resistive switching phenomena were realized by utilizing the applied bias-dependent charge trapping, holding, and recombination on the available states at vacuum-deposited aluminum nanostructures. The effect of CP backbone conformation on the vertical charge transport was also analyzed via a comparative study of three thiophene-based polymers namely RR-P3HT, PBTTT, and PTB-7. It was revealed that CPs with relatively fewer hydrophobic side chains was more favorable for the facile vertical charge transport due to its preferred face-on conformation on the hydrophilic liquid substrate used in UFTM. It was demonstrated that a non-volatile bistable resistive memory switch fabricated using UFTM-processed oriented thin films of PTB-7 exhibited a remarkably high on-off ratio of 1.5 × 106 with high durability.

DOI： https://doi.org/10.1016/j.mtelec.2023.100043

Kyutacar

Other Link： https://www.sciencedirect.com/science/article/pii/S2772949423000190

Controlling the electrocatalytic activities of conducting polymer thin films toward suitability as cost-effective counter electrodes of dye-sensitized solar cells Reviewed International journal

Yuki Kurokawa, Takehito Kato, Shyam S. Pandey

Synthetic Metals ( Elsevier ) 220 117362(1) - 117362(8)) 2023.05

Authorship：Last author,　Corresponding author Language：English Publishing type：Research paper (scientific journal)

Role dopant anions and solvents in electropolymerized conducting polymers (CPs) on controlling the
morphology of thin films and electrocatalytic activities to judge their suitability as low-cost counter electrodes (CE) of dye-sensitized solar cells ( DSSCs) was systematically investigated. Amongst various CPs such as polyaniline (PANI), polypyrrole (PPy), and PEDOT with sodium dodecyl sulfate (SDS) as a dopant, PEDOT was found to exhibit the best photovoltaic performance with a photoconversion efficiency (PCE) of 6.99 %. This was attributed to the best lectrocatalytic activity due to the smallest ΔEp, most minor R1, and nano-morphologyassisted high surface area, as confirmed by CV, EIS, and FE-SEM investigations. Using PEDOT as CP, the nature of dopants such as SDS, TFSI, and ClO4 has also been found to control the electrocatalytic activities and the morphology of the fabricated thin films affecting overall photovoltaic performance DSSCs. Amongst the various CP-based CE fabricated using different dopants and solvents, PEDOT:TFSI thin films prepared in acetonitrile solvent and used as CE exhibited not only the best electrocatalytic activity as CE but also demonstrated the best
photovoltaic performance with PCE of 7.0 %, which almost similar to that of DSSC utilizing Pt as CE with PCE of 7.1 %. Therefore, it was concluded that the nature of CP and dopant ions were vital factors in governing the electrocatalytic activities of the thin films to ensure their suitability as CE for optimal functioning and controlling the DSSC performance.

DOI： https://doi.org/10.1016/j.synthmet.2023.117362

Kyutacar

Other Link： https://www.sciencedirect.com/science/article/pii/S037967792300084X?via%3Dihub

3. Design and Synthesis of Novel NIR Sensitive Unsymmetrical Squaraine Dyes for Molecular Photovoltaics Reviewed

Safalmani Pradhan Yuki Kurokawa Shyam S Pandey

Physica Status Solidi-A ( Wiley ) 220 ( 24 ) 2300145(1) - 2300145(10) 2023.04

Authorship：Last author,　Corresponding author Language：English Publishing type：Research paper (scientific journal)

Two novel near-infrared (NIR)-sensitive unsymmetrical squaraine dyes, SQ-258 and SQ-259, for their suitability as a sensitizer in dye-sensitized solar cells (DSSCs) are designed and synthesized, followed by photophysical and photovoltaic characterizations. It is demonstrated that introducing a 1,3-indandione acceptor unit in the central squaric acid core of SQ-259 leads to the suppression of dye aggregation owing to its nonplanar molecular geometry and the broadening of the optical absorption and photon-harvesting window up to 800 nm. Owing to the extended wavelength photon harvesting, SQ-259 improves the photoconversion efficiency (PCE) compared to its SQ-258 dye counterpart. However, despite its wide wavelength photon harvesting, the improvement in the PCE of SQ-259 is less pronounced, and this is attributed to the small driving force for injection of electrons (0.29 eV), hampered electronic coupling, and decreased electron lifetime for resistance to recombination (7.9 ms), which is confirmed by the cyclic voltammetry, quantum chemical calculation, and electrochemical impedance spectroscopic investigations, respectively.

DOI： https://doi.org/10.1002/pssa.202300145

Kyutacar

Highly Conductive Graphenated-Carbon Nanotubes Sheet with Graphene Foliates for Counter Electrode Application in Dye-Sensitized Solar Cell Reviewed International journal

Yusnita Yusuf, Suhaidi Shafie, Ismayadi Ismail, Fauzan Ahmad, Mohd Nizar Hamidon, Pandey Shyam Sudhir and Lei Wei

Journal of Science and Technology ( UPM, Malaysia ) 31 ( 3 ) 2023.03

Language：English Publishing type：Research paper (scientific journal)

This work enlightened the synthesis of graphenated-carbon nanotubes sheet (g-CNT) using the floating-catalyst chemical vapor deposition method (FCCVD) for dye-sensitized solar cell (DSSC) application. The carbon injection flow rate in the experiment was varied to 6, 8, and 10 ml/h. The morphological findings revealed that the g-CNT formed a highly conductive network. Excellent conductivity was obtained for the sample g-CNT8 (34.5 S/cm) compared to the sample g-CNT6 (11.2S/cm) and CNT10 (4.76 S/cm). This excellent feature is due to the hybrid structure of the g-CNT8, which creates efficient electron transfer in the materials resulting in higher conductivity. The hybrid structure provides a high surface area that improves conductivity. Therefore, the g-CNT sheet is an excellent candidate to replace the conventional platinum used as a counter electrode (CE) in DSSC.

DOI： 10.47836/pjst.31.3.12

Other Link： http://www.pertanika.upm.edu.my/pjst/browse/prepress-issue?article=JST-3570-2022

Optical and dielectric realisation of biomolecular detection using gold nanoparticles bio-conjugate with liquid crystal Reviewed International journal

Lokesh K. Gangwar, Vikash Sharma, Amit Choudhary, Gajjala Sumana, Shyam .S. Pandey, Hirofumi Tanaka, Ashok M. Biradar, Rajesh

Journal of Molecular Liquids ( Elsevier ) 380 121754 2023.03

Language：English Publishing type：Research paper (scientific journal)

Dielectric biosensor based on nematic liquid crystal platform has been fabricated using sandwich immunoassay technique for the detection of a biomolecule, human cardiac troponin I (cTnI). The optical response of Liquid crystal (LC) biosensor and its corresponding frequency-dependent dielectric properties have been investigated as a function of cTnI concentration. Gold nanoparticles conjugate with detection antibody (AB-GNP) is used for the enhancement of both the optical and dielectric signal of the biosensor. AB-GNP binding with cTnI alter the surface energy of the substrate causing disturbances in LC alignment resulting in a change in transmission. The transmission of the LC cell has been found to be varying from dark to bright texture under polarized microscope as a function of cTnI concentration. A change in low-frequency permittivity with increasing cTnI concentration that forms an increasing order of sandwich immunocomplex with AB-GNP revealed an interfacial surface phenomenon. A positive shift in the onset frequency of permittivity is observed due accumulation of immunocomplex with increasing concentration of cTnI at electrode/LC interface. The dielectric response
of the biosensor is fitted with Hill-Langmuir equation over a concentration range of 0.01 to 10 ng mL−1 cTnI. The dissociation constant ‘Kd’ of 1.02 ± 0.24 ng/mL−1 indicates strong cTnI binding affinity for substrate antibody. A nearby value of 1, calculated for Hill coefficient ‘n’ revealed no co-operativity characteristic of cTnI binding to the primary capture antibody, wherein each binding site of the antibody functions independently at the electrode surface, causing accumulation of charged species revealing LC interfacial surface electrical property.

DOI： 10.1016/j.molliq.2023.121754

Other Link： https://www.sciencedirect.com/science/article/pii/S0167732223005573?via%3Dihub

Bifacial Dye-Sensitized Solar Cells Utilizing Visible and NIR Dyes: Implications of Dye Adsorption Behaviour Reviewed International journal

Suraya Shaban, Ajendra K Vats, Shyam S Pandey

Molecules ( MDPI ) 28 ( 6 ) 2784 2023.03

Authorship：Last author,　Corresponding author Language：English Publishing type：Research paper (scientific journal)

Bifacial dye-sensitized solar cells (DSSCs) were fabricated utilizing dye cocktails of two dyes, Z-907 and SQ-140, which have complementary light absorption and photon harvesting in the visible and near-infrared wavelength regions, for panchromatic photon harvesting. The investigation of the rate of dye adsorption and the binding strengths of the dyes on mesoporous TiO2 corroborated the finding that the Z-907 dye showed a rate of dye adsorption that was about >15 times slower and a binding that was about 3 times stronger on mesoporous TiO2 as compared to SQ-140. Utilizing the dye cocktails Z-907 and SQ-140 from ethanol, the formation of the dye bilayer, which was significantly influenced by the ratio of dyes and adsorption time, was demonstrated. It was demonstrated that the dyes of Z-907 and SQ-140 prepared in 1:9 or 9:1 molar ratios favoured the dye bilayer formation by subtly controlling the adsorption time. In contrast, the 1:1 ratio counterpart was prone to form mixed dye adsorption; the best performance of the BF-DSSCs was shown when a dye cocktail of Z-907 and SQ-140 in a molar 9:1 ratio was used to prepare a photoanode for 1 h of dye adsorption. The BF-DSSCs thus exhibited PCEs of 4.23% and 3.48% upon the front and rear side light illuminations, a cumulated PCE of 7.71%, and a very good BBF of 83%.

DOI： https://doi.org/10.3390/molecules28062784

Kyutacar

Other Link： https://www.mdpi.com/1420-3049/28/6/2784

Bioactive potential of morin loaded mesoporous silica nanoparticles: A nobel and efficient antioxidant, antidiabetic and biocompatible abilities in in-silico, in-vitro, and in-vivo models Reviewed International journal

Rout George Kerry, Kshitij RB Singh, Subhasis Mahari, Atala Bihari Jena, Bijayananda Panigrahi, Kahnu Charan Pradhan, Satyanarayan Pal, Bhagaban Kisan, Jagneshwar Dandapat, Jay Singh, Shyam S Pandey, Ravindra Pratap Singh, Sanatan Majhi

Open Nano ( Elsevier ) 10 100126 2023.02

Language：English Publishing type：Research paper (scientific journal)

Developing a delivery system has become crucial in engineering cutting-edge next-generation theranostic approaches. Therefore, in the present research work, a customized Mesoporous silica nanoparticle (MSiNPs) was designed by adapting the Stöber method with silane polymerization for Morin (MO) adsorption. The average size of MSiNPs was 50–130 nm as measured by TEM, while FE-SEM revealed a spherical surface shape. According to Raman and FTIR spectra, while the synthesis of MSiNPs, CTAB (a surfactant) was eliminated from MSiNPs, silane was functionalized, and with a loading efficiency of 10.28 ± 0.22%, MO was adsorbed. Molecular docking was used to perform in-silico studies to investigate the interaction of native MO with antidiabetic and antioxidant enzymes. Furthermore, the antioxidant and antidiabetic effects of both MO adsorbed MSiNPs, and native MO were examined in vitro, with the former showing promise even at lower concentrations than the latter. The cell survival experiment on Mouse macrophages RAW 264.7 and HCT cells revealed that MO adsorbed MSiNPs were nontoxic up to 15 μg/ml. The acute toxicity of different concentrations of MO adsorbed MSiNPs was also conducted in an in vivo model zebrafish (Danio rerio), where the study was conducted for about 96 h and evaluated for histological significance. The findings described above revealed that the MSiNPs were electrochemically, structurally, and thermally stable and MO adsorbed MSiNPs were nontoxic and biocompatible, implying that it might be an effective drug delivery vehicle for MO in the future. Moreover, in coming times, this nano-delivery system with effective biodistribution of the adsorbed MO could be explored as an antidiabetic and anti-cancer agent.

DOI： https://doi.org/10.1016/j.onano.2023.100126

Other Link： https://www.sciencedirect.com/science/article/pii/S2352952023000063

Improving vertical charge transport in organic Schottky diodes via Interface engineering of large-area conducting polymer thin films fabricated on hydrophilic liquid surface of tunable surface energy Reviewed International journal

Subhajit Jana, Nikita Kumari, Shyam S Pandey, Rajiv Prakash

Applied Surface Science ( Elsevier ) 616 156377 2023.01

Language：English Publishing type：Research paper (scientific journal)

Molecular orientation and stacking genre proved to be one of the decisive factors for the performance of conducting polymer (CP) based electronic devices. In this context, harnessing the key advantages of the ribbon shaped “floating-film transfer method” (FTM) along with an interfacial engineering approach has been utilized for molecular rearrangement in polymer thin-films formed on the surface of a high surface energy hydrophilic liquid mixture. In this novel subphase modified floating-film transfer method (SM-FTM), dodecyl benzene sulfonic acid (DBSA) has been used to control the molecular backbone stacking proximate to the solution-liquid interface and regioregular-poly(3-hexylthiophen-2,5-diyl) (rr-P3HT) was used as the model CP to probe the polymer-DBSA interaction. The molecular arrangements in microcrystalline domains, electronic band structures, and the evolution of surface texture at the solution-liquid interface have been investigated through multiple characterization tools. After that, the electrical performances of Schottky barrier diodes (SBDs) were studied in an ITO/P3HT/AlOx/Al sandwiched structure and a dramatic enhancement of rectification ratio up to 8.2 × 106 at ± 6 V was achieved. Further, an analytical model for SM-FTM, developed using lubrication theory and thin-film dynamics, has also been presented to elucidate the polymer spreading dynamics and the mechanism of molecular rearrangement at the interface.

DOI： https://doi.org/10.1016/j.apsusc.2023.156377

Other Link： https://www.sciencedirect.com/science/article/pii/S0169433223000533

Cylindrical transparent conductive oxide-free dye-sensitized solar cells with treated flat titanium sheet Reviewed International journal

Azwar Hayat, Ajay Kumar Baranwal, Masaki Nakamura, Fujisawa Shigeki, Shyam S Pandey, Shuzi Hayase

Journal of Photonics for Energy ( SPIE ) 2022.12

Language：English Publishing type：Research paper (scientific journal)

Conventional dye-sensitized solar cells (DSSCs) require two transparent conductive oxide (TCO) glasses as working and counter electrodes and are one of the most costly components posing an appreciable cost burden for production and commercialization. To circumvent this issue, we propose a TCO-free device structure utilizing titanium (Ti) sheets as a substitute for TCO. This back contact device structure not only allows the removal of the costly TCO component from the working electrode but also enhances the extent of photons absorbed by the photoanode. A flat titanium sheet with microholes (FTS-MH) was successfully applied to fabricate cylindrical TCO-free-DSSCs) with a titanium sheet as a back contact electrode. When the H2O2 surface-treated FTS-MH substrate generating dense anatase TiO2 nanosheets was used as a photoanode, there was a pronounced improvement in efficiency from 5.76% to 8.59%. This was mainly attributed to the lower interfacial resistance facilitated by improved electrical contact between the conducting FTS-MH substrate and mesoporous TiO2 layer since enhancement in the dye loading was only 8.6%.

DOI： https://doi.org/10.1117/1.JPE.12.045502

Other Link： https://www.spiedigitallibrary.org/journals/journal-of-photonics-for-energy/volume-12/issue-4/045502/Cylindrical-transparent-conductive-oxide-free-dye-sensitized-solar-cells-with/10.1117/1.JPE.12.045502.short

Controlling the molecular orientation of a novel diketopyrrolopyrrole-based organic conjugated polymer for enhancing the performance of organic field-effect transistors Reviewed International journal

Moulika Desu, Shubham Sharma, Kuang-Hao Cheng, Yu-Han Wang, Shuichi Nagamatsu, Jyh-Chien Chen, Shyam S Pandey

Organic Electronics ( Elsevier ) 113 106691 2022.11

Authorship：Last author,　Corresponding author Language：English Publishing type：Research paper (scientific journal)

A novel organic conjugated copolymer p(DPP-BZC) was utilized as a solution-processable organic semiconductor and its large area of the unidirectionally oriented thin film was fabricated by the Ribbon-shaped floating film transfer (FTM) method. Organic field-effect transistors (OFETs) fabricated using oriented thin films of this polymer demonstrated a clear p-type semiconducting behaviour and anisotropic charge carrier transport. A maximum orientation with a dichroic ratio of 5.1 was obtained in the FTM-processed thin film under optimized condition with liquid substrate viscosity, temperature and polymer solution concentration of 6.12 cst, 50 °C and 3% (w/v), respectively. Out-of-plane XRD and in-plane GIXD results revealed that oriented thin films of this copolymer are semicrystalline and adopt purely edge-on conformation. The implication of surface modification of Si/SiO2 gate dielectric utilizing HMDS. OTS and CYTOP on the charge carrier transport revealed that substrate with high-surface-energy hampers the on/off ratio, operating voltage and charge carrier mobility (μ). On the other hand, Si/SiO2 substrate treated with CYTOP having relatively lower surface energy demonstrated the best device performance with the highest μ of 2.7 x 10−2 cm2/Vs, which is > 30 times higher as compared to that of its non-oriented spin-coated device counterparts an μ of 8.0 x 10−4 cm2/V

DOI： https://doi.org/10.1016/j.orgel.2022.106691

Kyutacar

Other Link： https://www.sciencedirect.com/science/article/pii/S1566119922002634

Mechanical Modelling and Stress-Strain Prediction of Electroactive Polymer-Based Capacitive Sensor under Multiaxial Loads using Uniaxial Tensile Data Reviewed International journal

Nitin Kumar SINGH, Kazuto TAKASHIMA and Shyam S. PANDEY

Sensors and Transducers ( IFSA Publishing ) 259 ( 5 ) 12 - 18 2022.10

Authorship：Last author,　Corresponding author Language：English Publishing type：Research paper (international conference proceedings)

In this paper, mechanical modelling and stress-strain prediction of the ionic type of electroactive polymer (EAP)
based capacitive strain sensor under multiaxial loading has been performed using uniaxial tensile data. A highly stretchable
sensor with > 400 % strain was fabricated using Styrene-ethylene-butylene-styrene (SEBS) rubber and Dodecyl benzene
sulphonic acid (DBSA) doped polyaniline (PANI) composite material as a dielectric film, and carbon grease as top and bottom
electrodes. From uniaxial tensile measurements, a three-dimensional constitutive model of the EAP strain sensor was validated.
Experimental data obtained from the uniaxial tensile measurement was fitted according to the Ogden-based constitutive
mathematical model. For predicting the stress-strain behaviour of the sensor under the multiaxial loads, 2nd term of the Ogden
model was demonstrated to fit well with uniaxial tensile data. Such modelling can play a significant role in designing any type
of EAP-based sensor for various operations under variable loading conditions.

Other Link： https://www.sensorsportal.com/HTML/DIGEST/october_2022/Vol_259/P_3275.pdf

Unraveling the Implications of Macromolecular Orientation on the Planar and Vertical Charge Transport in Organic Electronic Devices Reviewed International journal

Shubham Sharma, Ajendra Kumar Vats, Manish Pandey, Shuichi Nagamatsu, Jyh-Chien Chen, Shyam S Pandey

ACS Applied Polymer Materials ( American Chemical Society ) 4 ( 11 ) 8315 - 8323 2022.10

Authorship：Last author,　Corresponding author Language：English Publishing type：Research paper (scientific journal)

The role of film morphology of conjugated polymers (CPs) and their macromolecular conformation with respect to the substrate in governing charge transport and overall device performances has been a matter of debate. The nature of the macromolecular orientation of CPs in thin films has a pivotal role in controlling the performance of planar and sandwich devices. Thin-film characterizations unveiled that spin-coated films are isotropic with mixed edge-on/face-on conformation, whereas unidirectional floating film transfer method (UFTM) films are anisotropic with edge-on-oriented micrometer-sized ordered domains. To unravel the explicit role of molecular orientation on device performance, two types of devices, organic Schottky diodes (OSDs) for out-of-plane carrier transport and organic field-effect transistors (OFETs) for in-plane charge transport, were fabricated and characterized. Isotropic and relatively low crystalline spin-coated films exhibited superior transport characteristics in the out-of-plane direction than UFTM films irrespective of the crystallinity. On the other hand, edge-on-oriented UFTM thin films demonstrated remarkably enhanced in-plane charge transport with more than two orders of magnitude of enhancement in the field-effect mobility. The nature of molecular orientation of different films is significantly correlated with the performance of the OSDs and OFETs.

DOI： https://doi.org/10.1021/acsapm.2c01283

Kyutacar

Other Link： https://pubs.acs.org/doi/full/10.1021/acsapm.2c01283

Synthesis and Characterization of Newly Designed and Highly Solvatochromic Double Squaraine Dye for Sensitive and Selective Recognition towards Cu2+ Reviewed

Linjun Tang, Shubham Sharma, Shyam S Pandey

Molecules ( MDPI ) 27 ( 19 ) 6578 2022.10

Authorship：Last author,　Corresponding author Language：English Publishing type：Research paper (scientific journal)

Synthesis and characterization of a novel and zwitterionic double squaraine dye (DSQ) with a unique D-A-A-D structure is being reported. Contrary to the conventional mono and bis-squaraine dyes with D-A-D and D-A-D-A molecular frameworks reported so far, DSQ dye demonstrated strong solvatochromism allowing for the multiple ion sensing using a single probe by judicious selection of the suitable solvent system. The DSQ dye exhibited a large solvatochromic shift of about 200 nm with color changes from the visible to NIR region with metal ion sensitivity. Utilization of a binary solvent consisted of dimethylformamide and acetonitrile (1:99, v/v), highly selective detection of Cu2+ ions with the linearity range from 50 μM to 1 nM and a detection limit of 6.5 × 10−10 M has been successfully demonstrated. Results of the Benesi–Hildebrand and Jobs plot analysis revealed that DSQ and Cu2+ ions interact in the 2:1 molecular stoichiometry with appreciably good association constant of 2.32 × 104 M−1. Considering the allowed limit of Cu2+ ions intake by human body as recommended by WHO to be 30 μM, the proposed dye can be conveniently used for the simple and naked eye colorimetric monitoring of the drinking water quality.

DOI： https://doi.org/10.3390/molecules27196578

Other Link： https://www.mdpi.com/1420-3049/27/19/6578

Electronic versus Ionic Electroactive Polymers (EAPs) Strain Sensors for Wearable Electronics: A Comparative Study Reviewed

Nitin Kumar Singh, Kazuto Takashima, Shyam Sudhir Pandey

Engineering Proceedings ( Multidisciplinary Digital Publishing Institute ) 21 ( 1 ) 2022.08

Authorship：Last author,　Corresponding author Language：English Publishing type：Research paper (international conference proceedings)

Electroactive polymer (EAP) strain sensors have gained appreciable attention as a potential candidate for their application in the area of soft electromechanical devices and have been widely used in soft robotics, healthcare, augmented reality, and wearable devices. In this research, a systematic comparison has been made by fabricating the electronic and ionic types of capacitive EAP strain sensors. To accomplish this, a combination of silicone rubber sandwiched between silver-coated stretchable fabric electrodes is used as an electronic type of EAP sensor, while a conducting and stretchable freestanding film consisting of Styrene-ethylene-butylene-styrene (SEBS) rubber and dedocyl benzene sulfonate acid (DBSA) doped polyaniline composite film sandwiched between carbon grease electrodes is chosen as an ionic type of EAP sensor. Mechanical characterization in terms of the uniaxial tensile testing was …

DOI： https://doi.org/10.3390/engproc2022021001

Other Link： https://www.mdpi.com/2673-4591/21/1/1

Fabrication, characterization and modelling of the fabric electrode-based highly stretchable capacitive strain sensor Reviewed

Nitin Kumar Singh, Kazuto Takashima, Shyam S Pandey

Materials Today Communications ( Elsevier ) 32 104095 2022.07

Authorship：Last author,　Corresponding author Language：English Publishing type：Research paper (scientific journal)

Highly stretchable and capacitance-based strain sensors were fabricated utilizing highly stretchable silicone elastomer as dielectric film sandwiched between the conducting and stretchable cloth-based top and bottom electrodes. Electromechanical characterizations for the proposed sensor after multiple and reversible loading and unloading cycles up to 150% applied strain were conducted followed by the modelling of the sensing performance. It has been shown that the sensor exhibits reproducible electromechanical performance under multiple reversible stretching and relaxation cycles. There was a very small deviation (< 10%) in the observed values of the capacitance upon the applied strain of 150% up to the 1000 loading and unloading cycles. Tensile measurement for the sensor under various applied strains, not only exhibits almost constant force indicating negligible Mullins effect and negligible time-dependent changes at a fixed strain up to 100% suggesting that viscoelastic losses can also be neglected. From uniaxial tensile experiments, constitutive model of the dielectric elastomer sensor was validated. For the fitting of the experimental data obtained from the uniaxial tensile measurement, a variety of strain energy formulations have been compared for predicting the constitutive behaviour of sensor using the Mooney– Rivlin, Neo-Hookean, Yeoh and Ogden models, where 2nd term of the Ogden model was found to explain the experimental tensile data most accurately. To explain some observed losses at 150% of applied strain, the Prony series-based time dependent model was used for predicting stress at any value of time and it was found that experimental data was well fit with 4th order of Prony series.

DOI： https://doi.org/10.1016/j.mtcomm.2022.104095

Other Link： https://www.sciencedirect.com/science/article/pii/S2352492822009473

Fabrication and Characterization of Oriented Thin Films of DPP-based Conjugated Copolymer Prepared by Friction Transfer Method Reviewed

Yuki Kurokawa, Ajendra K Vats, Shuichi Nagarnatsu, Shyam S Pandey

IEEE Explore ( IEEE ) 124 - 127 2022.07

Authorship：Last author,　Corresponding author Language：English Publishing type：Research paper (international conference proceedings)

Japan http://www.amfpd.jp/ 2022.07.05 - 2022.07.08

DOI： 10.23919/AM-FPD54920.2022.9851297

<PANDEY Shyam sudhir>

Papers - PANDEY Shyam sudhir