Journals
2025 EN
Paria Sarbaranjan · Sahu Pranabesh · Ko Jae Young
+2 more
ABSTRACT Liquid rubbers have recently emerged as essential processing aids, acting as processing oils that preserve the mechanical properties of the base rubber while supporting long‐term sustainability. These rubbers are primarily low molecular weight materials with significant viscous flow at room temperature. Notably, during vulcanization, they form crosslinks with the primary rubber chains, enhancing or maintaining the performance of the final compounds. In light of cost, product longevity, energy efficiency, and environmental concerns, liquid rubber‐based processing oils show potential as an alternative to the highly aromatic oils commonly used in the rubber industry, offering long‐term functionality through environmentally safer processes. In this study, for the first time, we developed a bio‐based liquid rubber using farnesene (FA) and dibutyl itaconate (DBI), styrene (Sty), and recycled styrene (rSty) via a straightforward and eco‐friendly Diels‐Alder (DA) reaction. The successful preparation of a homopolymer of FA and its copolymer with DBI, Sty, and rSty was examined by nuclear magnetic resonance (NMR) and Fourier‐transform infrared (FTIR) spectroscopy. Additionally, gel permeation chromatography (GPC) was employed to determine the molecular weight and polydispersity index of the synthesized liquid rubbers. Thus, the results indicated that the produced liquid rubbers have notable properties, stating their applicability for industrial purposes.
Journals
2025 EN
Prabhakar Om Prakash · Sahu Dhananjay · Sahu Raj Kumar
+2 more
ABSTRACT This work investigates the electrical, mechanical, and electromechanical behavior in a cost‐effective acrylic elastomer named Bapna Tape (BPT by Bapna Enterprises, India) exhibiting similar stretchability and functionality as VHB 4910 (3M, USA) dielectric elastomer for soft actuator towards artificial muscle. Herein, an in‐house fabricated planar actuator using BPT is subjected to static electrical loading voltage up to failure to identify the optimal pre‐strain (λ p) for maximum actuation. Actuators with optimal pre‐strain are tested under dynamic electrical loading to assess reliability, feasibility, and sustainability for artificial muscle applications by analyzing actuation performance and electrical breakdown strength. The relative permittivity (ε r) of both materials is found to be nearly 4.7, with a minimal1.8 %difference, while the elastic modulus of BPT at low strain aligns with that of VHB 4910 elastomer. The results show that the actuator configured with 200% radial pre‐strained elastomer (λ p = 3 ) yields maximum actuation ( 141.27 % ) and electrical breakdown strength ( 6.7 kV ) under static loading. Whereas, dynamic electrical loading with optimum pre‐stain, the actuator exhibits increased actuation strain with higher residual strain in subsequent cycles. Prolonged exposure (100 s) to a constant elevated voltage increases actuation strain over time and shows direct proportionality to the applied voltage. Further, the electrical breakdown strength of BPT varies based on the history of electrical loading (static or dynamic). This work highlights the importance of evaluating the performance reliability of cost‐effective elastomers to aid in commercialization of DE towards artificial muscles.
Journals
2025 EN
Sahu Bhavana · Perumal R · Ramesh Babu G
ABSTRACT A prediction tool for the burning rate of composite solid propellants using an artificial neural network (ANN)‐based model is proposed. The methodology adopted can be divided into two parts (a) estimation of interaction between process variables using the Spearman rank‐order correlation method and (b) building an ANN‐based model to predict the burning rate from a trimmed dataset consisting of significant variables. A multilayer perceptron (MLP) neural network was fed with trimmed variables as input, and a backpropagation algorithm was used to solve the mathematical model in Python. ANN hyperparameters tuning was carried out using the Grid Search algorithm in Python. It was found that the ANN model can predict the average burning rate of a solid motor with high accuracy when compared with the average burning rate obtained from ballistic evaluation test motors. This methodology helps predict the burning rate from a propellant composition and mechanical and physical properties without firing ballistic evaluation motors (BEM).
Journals
2025 EN
Roy Akash · Johnson Vinith · Das Pramiti
+3 more
ABSTRACT The structural plasticity of proteins at the molecular level is largely dictated by backbone torsion angles, which play a critical role in ligand recognition and binding. To establish the anion‐induced cooperative arrangement of the main‐chain (mc) torsion, herein, we analyzed a set of naturally occurring CαNN motifs as “static models” for their anion‐binding competence through docking and molecular dynamics simulations and decoded its torsion angle influenced mc‐driven anion recognition potential. By comparing a pool of 20 distinct sets of CαNN motif with identical sequences in their “anion bound/present, aP” and “anion free/absent, aA” versions, we could discern that there exists a positive correlation between the “difference of anion residence time (ΔR T )” and “difference among the main‐chain torsion angle” of the aP and aA population. Notably, the anion interaction with CαNNs is locally energetically favorable even in a context‐free non‐proteinaceous environment and if the difference of the mc‐torsion angles involving the Cα −1 , N 0 , N 1 residues for a population is higher between the aP and aA state, the difference among the ligand R T is also greater. At the atomistic level, the accommodation of anion is highly synergistic and cooperatively sways the interacting mc‐atom torsions. By comparing the clustering of H‐bonding patterns, the free energy of binding, and R T in both states, we provide evidence that to establish favorable thermodynamics and kinetics of ligand accommodation in these short structural motifs, proper reorientation of local‐mc governed by torsions is a prerequisite. Our findings position the CαNN motif as a promising scaffold for peptidomimetic design and emphasize the critical role of loop region dynamics in protein structure–function relationships.
Journals
2025 EN
Ryu Sel Gi · Lee Inseung · Sahu Rajkumar
+3 more
The photoenhanced galvanic effect of a MoS 2 thin film deposited on a c‐Si solar cell with a goal of enhancing carrier collection is investigated. The MoS 2 contact layer is deposited by a spin coating process with a subsequent rapid thermal process. The nanostructured thin film showed a photogalvanic potential of 0.12 V and localized electric conductance and Coulomb blockade with a voltage interval of 0.01 V. The fabricated solar cell with the MoS 2 thin film on the n‐type emitter surface shows a short circuit current of 8.21 A, open circuit voltage of 0.614 V, and conversion efficiency of 14.3% compared to a reference cell without the MoS 2 layer.
Journals
2025 EN
Banerjee Sayak · Chetia Anupam · Sahu Satyajit
Quantum dot solar cells (QDSCs) with single absorber layers have seen limited efficiency improvements over the years. To overcome this, introducing a dual absorber layer is a promising strategy for enhanced light absorption and overall performance. This study employs two efficient quantum dot materials, PbS‐QD and copper zinc tin sulfide QD (CZTS‐QD), in a dual‐layer configuration. While single‐layer QDSCs using PbS‐QD and CZTS‐QD achieved efficiencies of 26.8% and 24.5%, respectively, the PbS‐CZTS dual absorber layer QDSC achieved an improved efficiency of 27.85%. However, performance is slightly reduced to 26.99% due to parasitic resistances and temperature effects. To counter this, a reflective optical filter is integrated at the back contact, restoring and boosting the power conversion efficiency (PCE) to 28.18%. Further improvement is achieved through interfacial engineering between the absorber and hole transport layer, addressing nonradiative recombination caused by trap states. The incorporation of a BiI 3 interfacial layer with optimized thickness enhances interface quality, resulting in a final PCE of 28.40%. This work highlights the synergistic role of dual absorber layers, optical management, and interfacial engineering in pushing the efficiency limits of QDSCs.
Journals
2025 EN
Banerjee Sayak · Chetia Anupam · Das Chayan
+1 more
The quest for ecofriendly solar technology has propelled the development of nontoxic quantum dot solar cells (QDSCs). In this article, we present a comprehensive analysis and optimization of 18 QDSC configurations, utilizing environmentally benign materials. Copper zinc tin sulfide (CZTS) and copper indium disulfide (CuInS 2 ) quantum dots serve as absorber layers, paired with nontoxic electron and hole transport layers. Our optimized configuration, featuring FTO/SnO 2 /CuInS 2 ‐QD/Cu 2 O/Au, achieves a power conversion efficiency (PCE) of 25.77% under standard conditions. Advanced simulations reveal that efficiency losses due to parasitic resistances are mitigated by incorporating optical filters, enhancing by 1.38% of the PCE. Furthermore, tandem integration of CuInS 2 ‐QD and CZTS‐QD devices in series results in an efficiency of 47.36%, demonstrating the potential for an efficient energy harvesting. Addressing temperature sensitivity and resistive losses, we propose innovative hybrid systems and material modifications to enhance operational stability. This article contributes to the development of sustainable and efficient QDSCs, aligning with global renewable energy goals while prioritizing environmental safety.
Journals
2025 EN
Panda Sangita R. · Pradhan Manoranjan · Mallik Sandipan
+1 more
We analyze the asymmetric doping‐dependent electron mobility μ of GaAs/InGaAs/GaAs quantum well field‐effect transistor (QWFET) structure. We consider doping concentrations, nd1 and nd2 , in the substrate and surface barriers, respectively, and study μ as a function of nd2 , taking ( nd1 + nd2 ) unchanged. An increase in nd2 decreases nd1 , yielding interesting changes in the occupation of subbands. For well width W < 164 Å, μ is due to single subband occupancy (SSO). Around W = 164 Å, there occurs first SSO, then double subband occupancy (DSO), and again SSO with an increase in nd2 . Near the transition of subbands, abrupt discontinuities in μ arise due to inter‐subband effects. Thus, high to low and then high values of μ are obtained, displaying almost flat‐like variations, symmetric about | nd 2 − nd1 | = 0. As W becomes wider, complete DSO occurs throughout the range of nd2 having reduced μ . Alternatively, keeping nd1 unchanged and by increasing nd2, μ raises due to enhanced N s , with a drop near the transition from SSO to DSO. Under SSO, μ is controlled by the ionized impurity and alloy disorder scatterings, while under DSO, the impurity scattering determines μ . Our analysis on μ can help to examine the inter‐subband effects on device characteristics of the QWFET system.
Journals
2025 EN
Chaudhary Akhilesh Kumar · Pandey Pallavi · Yadav Shivangi
+2 more
This study investigates a photodetector design using the nontoxic, all‐inorganic perovskite material RbGeI 3 , which is distinguished by its efficient light absorption and excellent photoelectric conversion properties. Incorporating copper bismuth thiocyanate (CBTS) and indium gallium zinc oxide layers, this design enhances charge transport, leading to a photodetector that exhibits exceptional sensitivity across the visible spectrum, along with a peak responsivity of 0.63 A W −1 and a detectivity of 1.37 × 10 13 Jones in the near‐infrared (NIR) at 900 nm. The proposed photodetector exhibits wide‐spectrum detection, encompassing both the visible range and the NIR region. These results position RbGeI 3 and CBTS as compelling alternatives to traditional photodetector materials such as Si‐Ge, InGaAs, ZnO, and GaN. Validation is achieved through simulations using the SCAPS‐1D simulator, underscoring the potential of perovskite materials for advanced photodetector applications.
Journals
2025 EN
Chetia Anupam · Das Chayan · Yadav Kritika
+1 more
Lead‐free double perovskites (DPs), such as Cs 2 AgBiI 6 , have garnered significant attention as sustainable alternatives to lead‐based perovskites for optoelectronic applications. However, challenges in defect management, interface engineering, and device optimization have limited their performance. Herein, a comprehensive design and optimization of a Cs 2 AgBiI 6 ‐based vertical photodetector using a combination of first‐principles density functional theory (DFT) and SCAPS‐1D simulations are presented. The DFT calculations reveal an indirect bandgap of 1.53 eV, ideal for visible‐light absorption and charge transport. Systematic optimization of the device architecture, including charge transport layers, thickness, doping concentrations, and defect densities, leads to an optimal structure of FTO/ReS 2 /Cs 2 AgBiI 6 /CdTe/Au. The optimized device achieves a responsivity of 0.552 A W −1 and a detectivity of 1.542 × 10 12 Jones at 700 nm illumination. Remarkably, the photodetector demonstrates excellent low‐power light detection capabilities, with responsivity and detectivity values of 0.72 A W −1 and 2.01 × 10 12 Jones, respectively, at an incident power of 0.03 W m −2 . These findings highlight the potential of Cs 2 AgBiI 6 ‐based DPs for sustainable, high‐performance photodetectors and provide a roadmap for their experimental realization and broader optoelectronic applications.