Article
Multidisciplinary Sciences
Junhyeok Kang, Yeongnam Ko, Jeong Pil Kim, Ju Yeon Kim, Jiwon Kim, Ohchan Kwon, Ki Chul Kim, Dae Woo Kim
Summary: Layered two-dimensional materials with interlayer structures can be used for organic solvent nanofiltration (OSN) membranes due to their precise molecular sieving ability and stability in harsh conditions. In this study, nanoporous graphene (NG) with a high density of sp(2) carbon domains was synthesized by microwave treatment and showed ultrafast organic solvent permeance and excellent stability. The membrane's molecular weight cut-off (MWCO) can be switched depending on the solvent type, allowing for the separation of multiple organic mixtures using a single membrane.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Anna Svalova, Vasiliy Brusko, Elza Sultanova, Maria Kirsanova, Timur Khamidullin, Iskander Vakhitov, Ayrat M. Dimiev
Summary: The study successfully synthesized a composite material of rGO/Ni with excellent catalytic properties, characterized the material and tested its catalytic performance, demonstrating its high efficiency in catalyzing reduction reactions and low cost characteristics.
APPLIED SURFACE SCIENCE
(2021)
Article
Chemistry, Physical
Revathi Kottappara, Shajesh Palantavida, Suresh C. Pillai, Baiju Kizhakkekilikoodayil Vijayan
Summary: A direct low-cost chemical reduction method is presented for the synthesis of the ternary Cu-Cu2O-CuO system, where the presence of graphene oxide helps limit the conversion of copper to copper oxide. The composition of the ternary system can be altered by adjusting the amount of copper precursor used, as confirmed by X-ray diffraction studies and XPS analysis of the synthesized nanocomposites. The enhanced catalytic efficiency of the composite nanostructures towards visible light photodegradation and hydride reduction reactions is attributed to the interaction between graphene sheets and copper, as well as the unique ternary composition of Cu2O-Cu-CuO.
SURFACES AND INTERFACES
(2021)
Article
Chemistry, Multidisciplinary
Yanhui Zheng, Xifeng Hou, Siqi Lv, Zichuan Ma, Xiaolong Ma
Summary: In this study, beta-cyclodextrin-modified reduced graphene oxide aerogels (beta-CD-rGOAs) were synthesized and used to remove hexamethyldisiloxane from biogas. Characterizations showed that beta-CD was grafted onto the surface of rGOAs as a cross-linking modifier, forming a three-dimensional, cross-linked porous structure. The maximum breakthrough adsorption capacity of L2 on beta-CD-rGOA was 111.8 mg g(-1) at 273 K, and the material could be regenerated by annealing at 80 degrees C, making it promising for L2 removal from biogas.
Article
Engineering, Environmental
Zijun Xie, Bo Sun, Hongying Lin, Meng Fu, Yi Zhang, Zequn Ma, Xiangming Li
Summary: In this study, a bifunctional catalyst was developed for simultaneous dephosphorylation and 4-nitrophenol (4-NP) reduction. The catalyst was obtained by in-situ growth of NiFe layered double hydroxide on reduced graphene oxide/polyelectrolytes assembly nanolayers. The results showed that the catalyst could activate dephosphorylation of para-nitrophenyl phosphate (p-NPP) at 20 degrees C and the catalytic efficiency increased with temperature. Furthermore, the by-product 4-NP formed through dephosphorylation was fully converted to 4-aminophenol by the catalyst within 15 minutes.
JOURNAL OF WATER PROCESS ENGINEERING
(2023)
Article
Spectroscopy
Meng Zhang, Xiangyu Zhang, Kai Zhao, Yunxia Dong, Wenrong Yang, Jingquan Liu, Da Li
Summary: The assembly of gold nanorods with reduced graphene oxide (AuNR@Lcyst-rGO) demonstrates high therapeutic efficiency and excellent biocompatibility in tumor photothermal therapy. The assembly shows high photothermal effect, stability, and suitability for human tissue applications.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2022)
Article
Chemistry, Physical
Manjunatha Kempasiddaiah, Rajib Samanta, Sonali Panigrahy, Sudip Barman
Summary: Recent reports have shown that bimetallic electrocatalysts can enhance the activity for electrochemical formate production during CO2 reduction. However, they suffer from issues such as poor selectivity and durability. In this study, the incorporation of reduced graphene oxide (rGO) into nanostructured bimetallic CuSnOx electrocatalysts (CuxSnOx/rGO) led to notable improvements in electrochemical CO2 reduction to formate production. The Cu0.33SnOx/rGO nanocomposite exhibited enhanced electrocatalytical activity and selectivity towards formate production, with higher formate faradaic efficiency compared to other nanocomposites.
ACS APPLIED ENERGY MATERIALS
(2023)
Article
Optics
Sander A. Mann, Nishant Nookala, Samuel C. Johnson, Michele Cotrufo, Ahmed Mekawy, John F. Klem, Igal Brener, Markus B. Raschke, Andrea Alu, Mikhail A. Belkin
Summary: Highly nonlinear optical materials with fast third-order nonlinear optical response are essential for all-optical photonic devices. By controlling the coupling rate in subwavelength patch antennas coupled to intersubband transitions in multi-quantum-well semiconductor heterostructures, a giant third-order nonlinear response can be achieved, enabling the creation of compact, low-power, highly nonlinear devices for optical power limiters and modulation elements.
Article
Materials Science, Composites
Qianqian Lan, Leyao Liu, Yunchen Wu, Chao Feng, Kaiqin Ou, Zicheng Wang, Yunpeng Huang, Yan Lv, Yue-E Miao, Tianxi Liu
Summary: The study presents a facile approach for the preparation of graphene-based membranes with shorter and straighter water pathways. The obtained porous rGO/phenolic nanomesh membranes exhibit ultrafast water permeation while maintaining high rejections. This work demonstrates a simple and efficient route to fabricate high-performance separation membranes using two-dimensional porous nanomaterials.
COMPOSITES COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Jianpeng Liu, Wenchang Zhang, Chang Cheng, Juncheng Zhu, Tianle Wang, Kun Ni, Zifeng Lin, Zefeng Guan, Yanwu Zhu, Jiliang Zhu
Summary: This study presents a rapid reduction method for graphene oxide (GO) by bringing GO foam into contact with semi-molten metals such as tin (Sn) and lithium (Li). The electrical resistance of GO foam is significantly reduced by its interaction with these metals, even in dry air. By employing tin foil and calcination, the rGO with remarkably lower electrical resistivity is fabricated, demonstrating its potential as an electrode material for lithium-sulfur batteries.
Article
Engineering, Environmental
Yu Gao, Yun Zhang, Xiaoming Cai, Hangjing Zhou, Zisong Kong, Xiaolong Ma, Lei Gao, Honglin Tan, Jinming Cai
Summary: Graphene oxide (GO) membranes can modulate their water permeability and dye retention by controlling the reduction temperature. These membranes have completely different dye rejection rates for methylene blue (MB) and methyl orange (MO), enabling the effective separation of MB and MO mixtures. This work provides a non-expensive and low-energy method to prepare nanofiltration membranes for the separation of different dyes and salts.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2023)
Article
Multidisciplinary Sciences
Fei Li, Jiuyi Zhu, Pengzhan Sun, Mingrui Zhang, Zhenqing Li, Dingxin Xu, Xinyu Gong, Xiaolong Zou, A. K. Geim, Yang Su, Hui-Ming Cheng
Summary: This study demonstrates the excellent performance of reduced graphene oxide (rGO) in extracting gold from e-waste, even at minute concentrations. By controlling the protonation of the oxidized regions of rGO, gold can be extracted exclusively, without contamination by other elements.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Yuhan Li, Milo S. P. Shaffer
Summary: This study demonstrates the novel use of confocal microscopy for high-resolution characterization, in situ laser reduction, and versatile patterning of graphene oxide (GO) films. The reduction process can be attributed to thermal transfer and accumulation, which can be controlled over multiple length scales. This technique allows for the fabrication of conductive reduced GO films and 3D microscale architectures, and provides a valuable tool for well-controlled and scalable fabrication.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Optics
Jian Xin, Yue Liang, Junhua Gao, Yuxiao Wang, Yinglin Song, Xueru Zhang
Summary: In this study, the time-dependent change in the effective permittivity of an Ag nanorod array in hyperbolic metamaterials (HMMs) is extracted, and the existence of an ultrafast recovery process is experimentally confirmed. The calculation based on the extracted nonlinear effective permittivity indicates that the ultrafast signal originates from the superposition of two slower recovery processes. These results reveal that the superposition of two nonlinear processes with different signs and recovery speeds can lead to faster signal recovery in the combined process.
Article
Engineering, Chemical
Liuqian Zhang, Jing Wang, Yu Zhang, Junyong Zhu, Jinghe Yang, Jingtao Wang, Yatao Zhang, Yong Wang
Summary: Organic solvent nanofiltration (OSN) membranes based on two-dimensional (2D) materials have excellent potential for solvent recovery. Inspired by leaf veins, the NPTs-rGO membrane shows outstanding performance in ultrathin molecular separation for organic solvent nanofiltration.
JOURNAL OF MEMBRANE SCIENCE
(2022)
Article
Engineering, Electrical & Electronic
Vaisshale Rathinasamy, Rama Rao Thipparaju, Nisha Flora Boby Edwin, Shyamal Mondal
Summary: The utilization of terahertz (THz) technology in beyond 5G and 6G communication is increasing rapidly due to high data rates and bandwidth demands, but there are still challenges in designing devices for THz frequencies. The photo-conductive antenna plays a crucial role in realizing ultrafast wireless THz communications, with research showing significant potential in this area.
MICROWAVE AND OPTICAL TECHNOLOGY LETTERS
(2022)
Article
Nanoscience & Nanotechnology
Subhajit Jana, Subhrajit Mukherjee, Shivakiran B. N. Bhaktha, Samit K. Ray
Summary: The study demonstrates the superior broadband photodetection characteristics achieved by integrating few-layer phosphorene with silver nanoparticles on a silicon platform. The hybrid structure shows strong light absorption and enhanced photoresponse compared to pristine phosphorene, with potential applications in future nanophotonic devices.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Physics, Multidisciplinary
Brijesh Kumar, Priyanka S. Choubey, B. N. Shivakiran Bhaktha
Summary: This study investigates the photophysical properties of pyrromethene 570-doped PMMA thin films at various dye concentrations, determining the optimal dye concentration for efficient light emission. The refractive index and gain coefficient of the thin film were estimated using ellipsometry and the variable stripe length method. High quality microdiscs were fabricated using soft imprint lithography, with the lasing characteristics of the WGM microdisc resonator evaluated.
EUROPEAN PHYSICAL JOURNAL-SPECIAL TOPICS
(2022)
Article
Materials Science, Multidisciplinary
Seemesh Bhaskar, Pratyusha Das, Venkatesh Srinivasan, Shivakiran B. N. Bhaktha, Sai Sathish Ramamurthy
Summary: The combination of Ag surface plasmon colloid and high refractive index Nd2O3 ‘Huygen’ sources successfully achieved photonic enhancement of fluorescence and polarized emission. The study reveals the synergistic effects of metal and dielectric plasmonics with photonic crystal interface, providing new insights for biophysicochemical research.
MATERIALS RESEARCH BULLETIN
(2022)
Article
Engineering, Electrical & Electronic
Vaisshale Rathinasamy, Rama Rao Thipparaju, E. Nisha Flora Boby, Shyamal Mondal
Summary: This paper investigates the performance and behavior of photoconductive terahertz antennas through numerical modeling, and optimizes the structural parameters of the interdigitated electrodes to improve the efficiency and performance of terahertz waves. This research is very useful for practical experiments in spectroscopy, imaging, and communication applications.
OPTICAL AND QUANTUM ELECTRONICS
(2022)
Article
Materials Science, Multidisciplinary
S. Sudha Maria Lis, K. Rajasimha, Kapil Debnath, V. Krishna Chaitanya, B. N. Shivakiran Bhaktha
Summary: In this study, the sol-gel fabrication and characterization of SiO2-TiO2 one-dimensional photonic crystal (1DPhC) waveguides embedded with a low-index defect layer are presented. Femtosecond laser micromachining was used for microfabrication on multilayer structures, and the waveguiding characteristics of the fabricated structures were studied. The results show that the fabricated 1DPhC channel waveguides have efficient light guiding properties and are suitable for applications in optical integrated circuits.
Article
Optics
Priyanka S. Choubey, Shailendra K. Varshney, B. N. Shivakiran Bhaktha
Summary: We investigate the properties of lasing systems with varying degrees of openness and intrinsic disorder. The study focuses on three different dye-doped polymer based lasing systems, including a planar waveguide random laser (PWRL) and two whispering gallery mode resonators (WGMRs) with different geometries. The results show that improved optical confinement in WGMRs leads to low threshold and fast saturation of lasing modes. Additionally, mode competition and bimodal probability distribution are observed in PWRL, while WGMRs exhibit unimodal distribution. The study also reveals the presence of spin glass behavior in PWRL but not in WGMRs. The non-zero value of spectral intensity fluctuation overlap parameter in WGMRs indicates the presence of intrinsic disorder.
JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS
(2022)
Article
Nanoscience & Nanotechnology
Subhajit Jana, Sourabh Pal, Shivakiran B. N. Bhaktha, Samit K. Ray
Summary: This study reports the enhanced photodetection properties of MoSe2/Au-ZnO vertical heterostructures by investigating the synergistic effect of Au nanoislands on the optical response of ZnO nanorods and MoSe2 nanoflakes. The plasmonic effects mediated strong light-matter interactions in the Au-ZnO hybrids, leading to energy transfer and enhanced signal throughout the operational bandwidth of the devices. The use of 2D/1D mixed-dimensional heterostructures and resonant coupling with strategically integrated plasmonic nanoislands make these devices highly responsive broadband photodetectors for future nanophotonic applications.
ACS APPLIED NANO MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Rina Mudi, Samik Mallik, Bhargavi Veeraghattam, Dipak Kumar Goswami, B. N. Shivakiran Bhaktha, Kapil Debnath
Summary: The optical Tamm state is an electromagnetic mode that exists at the interface between a periodic dielectric structure and a metal layer. This article presents a detailed study on the existence of optical Tamm states in opal-like three-dimensional photonic crystal structures and reveals the presence of a hybrid Tamm-PhC bandedge state between a corrugated metal layer and 3D-PhC. The nature of the hybrid Tamm-PhC bandedge states strongly depends on the thickness of the metal layer, and no mode hybridization was observed at the interface between flat metal and 3D-PhC.
Article
Materials Science, Multidisciplinary
Sarbojit Mukherjee, Khanindra Pathak, B. N. Shivakiran Bhaktha
Summary: This paper presents experimental results on contactless geometry dependent stress characterization and mapping in elastic polymer membranes using polarization and interferometric techniques. Three different geometries of PDMS membranes, namely rectangular, wedge, and bowtie shaped membranes, were studied. The stress was found to be concentrated at the static edge of the rectangular membrane, while in the wedge and bowtie shaped membranes, it was concentrated at the locations with narrower width. These facile methods can be helpful in designing stress-induced tunable optics and analyzing stress in polymer membranes during industrial production.
Article
Metallurgy & Metallurgical Engineering
Sarbojit Mukherjee, Dushasan Kundu, Khanindra Pathak, B. N. Shivakiran Bhaktha
Summary: Mine safety and miner quality of life depend greatly on mine illumination and communication. Implementing safe and efficient illumination systems is critical, especially in underground gassy coal mines. This study explores the design and implementation of solar-powered optical fiber-based illumination and proposes a Li-Fi-based communication system for underground coal mines. The potential of optical fiber-based solar, laser, and hybrid illuminations in underground mines is discussed, along with the design and fabrication of a Fresnel lens-based solar tracker. The installed optical fiber-based illumination system achieved over 70 lux illumination at the work plane and demonstrated simultaneous basic Li-Fi communication, providing benefits to the underground coal mining industry.
MINING METALLURGY & EXPLORATION
(2023)
Article
Optics
Renu Yadav, Patrick Sebbah, Maruthi M. Brundavanam, B. N. Shivakiran Bhaktha
Summary: Random lasers are highly susceptible to changes in the scattering medium due to disorder-induced feedback. By utilizing the sensitivity of lasing modes to perturbations in disordered systems, it is possible to map the regions of perturbation. A tracking parameter has been defined to locate the displacement region of a scatterer by a few nanometers, and numerical results show that the precision of the method increases with the number of modes. This proposed method opens up the potential application of random lasers in monitoring nanoscale displacement for single-particle detection and monitoring.
Article
Chemistry, Physical
Renu Yadav, Sourabh Pal, Subhajit Jana, Shuvajit Roy, Kapil Debnath, Samit K. Ray, Maruthi M. Brundavanam, B. N. Shivakiran Bhaktha
Summary: Metal nanoparticles can modify the emission of a dye emitter by manipulating the overlap of optical gain and localized surface plasmon resonance. This study investigates the interaction between metal nanoparticles and gain spectra in random lasers, and demonstrates the importance of spectral overlap in determining the performance of random lasers.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Renu Yadav, Sourabh Pal, Subhajit Jana, Shuvajit Roy, Kapil Debnath, Samit K. Ray, Maruthi M. Brundavanam, B. N. Shivakiran Bhaktha
Summary: Metal nanoparticles can modify the emission level of a dye emitter by tailoring the spectral overlap of the optical gain and localized surface plasmon resonance. This study investigates the scattering properties of plasmonic random lasers and finds that the degree of quenching in photoluminescence is proportional to the extent of spectral overlap. Under off-resonant conditions, the emission is dequenched, leading to a lower threshold for random lasing.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Multidisciplinary Sciences
E. Nisha Flora Boby, Jitendra Prajapati, Vaisshale Rathinasamy, Shouvik Mukherjee, Shyamal Mondal
Summary: This article presents a detailed study on interdigitated photoconductive antenna (IPCA) structures for efficient terahertz (THz) generation and detection. By optimizing the structure of IPCA, it can overcome limitations of traditional antennas and achieve higher efficiency and power in THz signals.
ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING
(2022)
