G. Murali

Korea National University of Transportation · Department of Polymer Science and Engineering

Very recently, MXene‐based wearable hydrogels have emerged as promising candidates for epidermal sensors due to their tissue‐like softness and unique electrical and mechanical properties. However, it remains a challenge to achieve MXene‐based hydrogels with reliable sensing performance and prolonged service life, because MXene inevitably oxidizes i...

Solution-based deposition has recently been proposed as a low-cost flexible electronics alternative. Therefore, the development of appropriate solution-processed materials for metal oxide semiconductor transistors has become more important. In recent years, high dielectric constant(k) polymer insulators have been developed that can withstand relati...

Polysilsesquioxanes (PSQs) have generated great interest as solution‐processable inorganic polymers for obtaining high‐dielectric‐constant (k) dielectrics. Engineering the side chains in PSQs can enhance the polarization characteristics and provide different functionalities, such as photopatternability and ferroelectric performance. In this study,...

MXene's two-dimensional (2D) morphology, metallic electrical conductivity, and optical transparency characteristics have been widely utilized to uplift the performance of diverse optoelectronic devices. In this study, we demonstrate a simple spin-coating of 2D MXene nanosheets on 1D GaN nanorods (NRs) to establish a van der Waals (vdW) Schottky jun...

Conventional design of all-solid-state battery limits the portable device fabrication due to sluggish interfacial contact, safety, and high manufacturing cost. Additionally, unfavorable Li-dendrite formation and low coulombic efficiency hinder the further use. This will lead to low energy density that cannot satisfy current energy demand for the po...

Resistive Random-Access Memory (RRAM) devices are recognized as potential candidates for next-generation memory devices, due to their smallest cell size, high write/erase speed, and endurance. Particularly, the resis-tive switching (RS) characteristics in oxide materials have offered new opportunities for developing CMOS-compatible high-density RRA...

Traditionally, NaYF4 and glass-based materials are considered the most efficient upconversion materials. However, those materials may show signs of thermal warping or risks of fracture during long-term service life in extreme environments. In contrast, SiAlON ceramics preserve their spectral and physical integrity during continuous use due to their...

Wollastonite (CaSiO3) is a well-known rock-forming mineral and an important constituent in ceramics and cement industries due to its outstanding mechanical, chemical, and thermal stabilities. Despite technological importance, functional properties such as photon upconversion in CaSiO3 wollastonite ceramics have not been studied. In this contributio...

Photocatalytic water splitting, CO2 reduction, and pollutant degradation have emerged as promising strategies to remedy the existing environmental and energy crises. However, grafting of expensive and less abundant noble-metal cocatalysts on photocatalyst materials is a mandatory practice to achieve enhanced photocatalytic performance owing to the...

Tin oxide (SnO2) and nitrogen-doped graphene quantum dots (N-GQDs) composite nanotubes (SnO2/N-GQD NTs) were fabricated by the electrospinning technique and followed by the thermal annealing method for the application in supercapacitor as an electrode. SnO2/N-GQD NTs with different ratio of N-GQDs were prepared by adding different ratios of N-GQDs...

MXene-integrated photovoltaic devices can be used to create optically transparent systems to produce electrical energy. MXenes, an emerging family of two-dimensional materials, have attracted a tremendous amount of interest for their use in various applications. In particular, their optical transparency, metallic conductivity, and large-scale proce...

Novel materials with intriguing qualities, which emerge from time to time as a result of the research community’s tireless efforts, are cornerstones for the advancement of science and technology. MXenes, a class of two-dimensional (2D) materials reported for the first time in 2011, tremendously upgraded the devices used for electromagnetic shieldin...

Light-activation of gas sensors is recognized as a potential alternative to the traditional thermal-activation that has several drawbacks such as high power consumption. However, strategies to exploit outstanding light-response characteristics of carbon quantum dots (CQDs) for light-activated gas sensing are not established effectively. In the pres...

Atomic force microscopy (AFM) is an extensively used advanced characterization technique for a nanoscale range of materials. This chapter clearly describes the importance and advantages of AFM, its working principles, modes of measurement, and its applications in interdisciplinary fields such as chemistry, materials science, and biology.KeywordsAto...

Solar energy–driven carbon dioxide (CO 2 ) reduction to valuable solar fuels/chemicals (e.g., methane, ethanol, and carbon monoxide) using particulate photocatalysts is regarded as one of the promising and effective approaches to deal with energy scarcity and global warming. The growth of nanotechnology plays an eminent role in improving CO 2 reduc...

Here in, we synthesized pure BiFeO3 (BFO) and Bi0.8-XCaXEr0.2FeO3 (x = 0.0, 0.05, 0.1, and 0.15 at.%) nanoparticles using sol–gel technique and investigated their optical, magnetic, and electrical properties. X-ray diffraction studies reveals structural transformation in BFO from the rhombohedral structure to orthorhombic, without forming any defec...

MXenes are interesting 2D materials that have been considered as attractive frontier materials for potential applications in the fields of energy and electronic devices due to their excellent optoelectronic properties including metallic conductivity and high optical transparency. However, it is still challenging to achieve compatibility for the as‐...

In article number 2010897, Yong Jin Jeong, Tae Kyu An, Insik In, Se Hyun Kim, and co-workers propose a clever strategy of engineering MXene inks for electrohydrodynamic jet printing to produce all printed logic circuits. This work could inspire further practical printed electronics by providing an option to manufacture electrodes in complex circuit...

Lightweight and multifunctional thermoconductive electromagnetic interference (EMI) shielding nanocomposites with excellent EMI shielding performance and heat dissipation are in high demand for the development of the next generation of highly integrated electronic devices. Herein, a scalable fabrication method for multifunctional nanocomposites wit...

Upconversion (UC) active photocatalysts that absorb light beyond UV-visible region and catalyse reactions using the collected upconverted (NIR to UV-visible) photon energy have received incredible attention in renewable solar hydrogen production and environmental remediation. In this study, we report a facile synthesis strategy to produce the NaYF4...

Carbon quantum dots (CQDs) are becoming a desirable alternative to metal-based QDs due to their high biocompatibility, low toxicity, ease of preparation, and unique photophysical properties. In the present study, a simple microwave-assisted synthesis using a domestic oven has been adopted to produce multifunctional CQDs from the ethlyenediaminetetr...

MXene is one of the rapidly emerging 2D material in the present era of materials science, and it finds increasing applications in energy storage fields. MXene is one of the most suitable electrode materials for futuristic energy storage devices.

The ladder-like polysilsesquioxanes containing both the bio-mimicking adhesive polycatechol and polyethylene oxide (CA-PEO-LPSQ) were synthesized as an organic-inorganic hybrid material and applied as a surface modifier for the preparation of a compatible polyethylene (PE) separator in high performing lithium ion batteries (LIBs). The dip-coating o...

: Herein, we demonstrate the ultraviolet (UV) light activated high performance room temperature NO gas sensor based on nitrogen-doped graphene quantum dots (NGQDs) decorated TiO2 hybrid structure. TiO2 employed in the form of {001} facets exposed rectangular nanoplate morphology, which is highly reactive for the adsorption of active oxygen species....

Coupling of graphene and its derivatives with organic moieties is one of the promising strategies to enhance the gas sensing performance. A novel ternary nanocomposite of p-Phenylenediamine-graphene oxide (PGO)/InGaN nanorods (NRs) probed as chemiresistive gas sensor for carbon monoxide (CO) in ppm concentrations. The InGaN NRs were grown by molecu...

Mussel‐inspired chemistry, motivated by the adhesive proteins secreted by mussels for attachment to wet surfaces, is an emerging technique for manipulating the surface properties of a variety of materials. Here, a facile mussel‐inspired poly(N‐vinyl pyrrolidone) (PVP) polymer encapsulation with trivial influence on inherent optical properties of pe...

Multiferroic BiFeO3 and Bi0.8-XGdXEr0.2FeO3 (X=0.0, 0.05, 0.1 & 0.15) nanoparticles have been prepared by sol-gel technique. The effect of Gd content (in Gd/Er co-dopant) on the structural, magnetic, dielectric, and optical properties of the BiFeO3 materials has been studied. X-ray diffraction analysis revealed rhombohedral to orthorhombic phase tr...

Tin oxide (SnO2) is one of the best metal oxide material for gas sensor applications. Pristine SnO2 nanotubes (NTs) were prepared by one-step electrospinning technique, and composite graphene oxide doped SnO2 NTs (GO-SnO2 NTs) were fabricated by dipping SnO2 NTs in a GO solution with suitable annealing treatment. In this work, the influence of GO o...

Ultrathin nanomaterials are very significant affiliates of the nanocrystalline materials family because of their unique properties of broad significance. In the present study, highly uniform atomically thick YF3 nanobelts and nanowires are fabricated using an oleylamine assisted colloidal chemical strategy. Reaction monitoring demonstrates that two...

In recent days, 2-dimensional materials (2D) have become auspicious for gas sensor applications. Usually, the gas kinetics is poor at room temperature (RT). Considering the power consumption, photon excitation is an alternative way to enhance the gas kinetics at RT. In this work, we demonstrated the gas sensing properties of molybdenum disulfide (M...

Although metal nanoparticles (NPs) have been widely reported, Au NPs functionalized reduced graphene oxide (rGO)/GaN nanorods (NRs) for multi-functional applications are rarely discussed. The rGO is a well known transparent electrode and has been considering an alternative electrode to ITO in the current optoelectronic community. In this work, Au N...

In this work, we report on p-Phenylenediamine (PPD) functionalized reduced graphene oxide (rGO)/Si hybrid-structure designed for UV photodetector applications (PD). The hybrid-structure was characterized by using Fourier Transform-infrared spectroscopy, X-ray photoelectron spectroscopy to confirm the formation of nano-hybrid structure and the exper...

Nowadays, oxide-based diluted magnetic semiconductor nanoparticles are the most reliable compounds, wherein they accommodate both spin as well as charge of the electron in single domain, means most preferable for the fabrication of spintronic devices. In this view, we report on new Ce1−xNixO2 (x = 0.00, 0.02, 0.04, 0.06, and 0.08) nanoparticles pre...

Owing to anisotropic light emission, an aligned quantum‐rods (QRs) array paired with LCD backlight offers a viable option to achieve the light polarization and enhance the color gamut. Herein, we present a facile approach for the fabrication of a functional film with unidirectional ordered QRs by utilizing solvent‐based UV‐curable reactive‐mesogen...

In the era of modern technology, the development of spintronic devices using diluted magnetic semiconductor nanoparticles has drawn significant attention from the world researchers. In this work, we report on novel Cu1−xMnxS (x = 0.00, 0.01, 0.03 and 0.05) compounds synthesized at room temperature through a simple precipitation method via EDTA as a...

Here, we studied the gas sensing response properties for acetone and formaldehyde by a chemiresistive nanocube In2O3@RGO heterostructure sensor. The nanocube In2O3@RGO heterostructure based sensor demonstrates a high response to acetone (∼85%) and formaldehyde (∼88%) at 25 ppm concentration and optimum working temperatures of 175 °C and 225 °C, res...

Synthesizing upconversion materials with 3-dimensional structures is of fundamental importance in understanding the relationship between their optical properties and their structures. In this paper, we report a simple but useful synthetic method to produce highly monodisperse 3-dimensional YF3:Yb³⁺/Er³⁺ microcrystals showing variable upconversion e...

In large liquid crystal displays, the image quality in an oblique viewing direction is a crucial issue. From this perspective, 8-domain polymer-stabilized vertical alignment (PS-VA) mode has been developed to suppress the color shift in oblique viewing directions, compared to that in 4-domain PS-VA mode. To realize the 8-domain PS-VA, the four doma...

We report a facile synthetic method for high-aspect-ratio YF3:Yb3+/Er3+ nanocrystals by controlling the composition of the precursor and salts to manipulate the structures of YF3:Yb3+/Er3+ nanocrystals. A controlled aspect ratio is attained by tuning the molar ratio of NH4+/RE3+ (NH4+ is the counter ion released from the fluoride precursor (NH4F) a...

The excellent physical and chemical properties of graphene have been extensively studied for both scientific interest and novel applications in devices, such as organic photovoltaics, fuel cells, biosensors, and display devices. One of its excellent two-dimensional electric properties is its high electron transporting capability which gives enormou...

In this paper, we report systematic investigations on the effects of Ni doping on the structural, optical, magnetic and photocatalytic characteristics of CuS nanoparticles synthesized by simplistic wet chemical co-precipitation route via EDTA molecules as templates. XRD studies confirmed that accurate phase formation of synthesized nanoparticles an...

Vertical alignment liquid crystal (LC) cell driven by in-plane field with 3-D polymer network exhibited no pooling mura under an external mechanical pressure; however, the operating voltage of the device was increased, because the polymer network hinders field-induced reorientation of LC. In this paper, we adopted a modified cell structure in which...

We report a novel polymer stabilisation of blue phase by a chiral agent itself without additional reactive monomers. In this way, the structural difference in phase stabilisation gives rise to novel electro-optic properties such as the hysteresis-free with low-operating voltages. The number of constituents in polymer-stabilised blue-phase mixture i...

The present work is planned for a simple, inexpensive, efficient approach for synthesizing of Cu1-xFexS (x = 0.00, 0.01, 0.03, 0.05 and 0.07) nanoparticles via simplistic chemical co-precipitation route by using ethylene diamine tetra acetic acid (EDTA) as a capping molecules. As synthesized nanoparticles was used as competent catalysts for degrada...

The color shift of 4-domain polymer-stabilized (PS)-vertical alignment (VA) in oblique viewing directions is a severe problem so that a 8-domain PS-VA is required to suppress the color shift. We propose a novel approach to form the 8-domain by controlling surface polar anchoring energy and patterned electrode width in two regions of a pixel. The ga...

Pristine and Co doped covellite CuS nanoparticles were synthesized in aqueous solution by facile chemical co-precipitation method with Ethylene Diamine Tetra Acetic Acid (EDTA) as a stabilizing agent. EDAX measurements confirmed the presence of Co in the CuS host lattice. Hexagonal crystal structure of pure and Co doped CuS nanoparticles were authe...

Anisotropically structured upconversion nanocrystals capable of exhibiting bright upconversion emission properties are a promising new class of high performance optical materials. In this study, we investigate a facile synthetic method for the new nanoplate structure of YF3:Yb3+/Er3+ with enhanced luminescence intensity. The shape of YF3:Yb3+/Er3+...

Nanoparticles of ZnS:Fe (0, 1, 3, and 5 at.%) were synthesized by a refluxing route at 80°C. All the samples exhibited cubic structure as revealed by X-ray powder diffraction studies. Blue emission of undoped samples was totally quenched by Fe doping. Magnetic measurements showed that the undoped ZnS was diamagnetic whereas all the doped samples we...

We are the first to report a systematic study on the structural, optical and magnetic properties of chromium and cobalt co-doped SnO2 nanoparticles synthesized by the simple co-precipitation method using polyethylene glycol (PEG) as capping agent. EDAX spectra confirmed the presence of Sn, O, Cr and Co elements in the samples with near stoichiometr...

We report the H2 and LPG gas sensing behavior of RGO/SnO2 QDs synthesized by surfactant assisted hydrothermal method. The RGO/SnO2 QDs based sensor shows high response ~89.3% to H2 and ~92.4% to LPG for 500 ppm test gas concentration at operating temperatures 200 °C and 250 °C, respectively. Further, the RGO/SnO2 QDs based sensor shows good selecti...

Defects in graphene governs electrical and optical properties. Although grain boundaries in graphene inevitably formed during large area synthesis process, which act as scattering centers for charge carriers to degrade mobility, have been studied extensively, point defects have been rarely investigated mainly due to the absence of facile observatio...

The fringe-field switching (FFS) mode that uses liquid crystals (LC) with negative dielectric anisotropy is used in high resolution FFS-LCD owing to its higher transmittance over positive LC. In this paper, the FFS mode with electrode width 1 µm and distances between the electrodes 1.5 µm is proposed. In such an electrode structure, operating volta...

Cadmium sulfide (CdS) semiconductor nanocrystals doped with Ni2+ have been synthesized via a solution-based method and employing 2-mercaptoehonal as a capping agent. The obtained nanocrystals were characterized using X-ray diffraction (XRD) and Diffuse reflectance spectroscopy studies (DRS). XRD results showed that the undoped CdS nanocrystals are...

The rutile phase Sn0.99-xMnxCr0.01O2 (x = 0.00, 0.01, 0.03, 0.05 and 0.07) nanoparticles were synthesized by facile chemical co-precipitation method using poly ethylene glycol (PEG) as a capping agent. The samples were characterized by EDAX to confirm the expected stoichiometry. The X-ray diffraction (XRD), transmission electron microscopy (TEM) an...

Pure and Cr (1, 3, 5 and 7 at%) doped SnO2 nanoparticles were synthesized in aqueous solution by a simple chemical co-precipitation method using polyethylene glycol (PEG) as a stabilizing agent. The effect of Cr doping on the structural, optical and magnetic properties of SnO2 nanoparticles was investigated. EDAX spectra confirmed the presence of S...

CdS microstructures with uniform rose-flower-like morphology were successfully synthesized on a large scale through the physical vapor deposition method. The morphology, crystal structure and optical properties of the final product were characterized using SEM, XRD, TEM, SAED, Raman spectroscopy and photoluminescence spectroscopy. The flower-like C...

CdS semiconductor with different morphologies have been achieved by simple thermal evaporation of CdS powder at 1050 °C in a flowing Ar atmosphere. The products were characterized by X-ray diffraction, Scanning electron microscopy, Transmission electron microscopy and Photoluminescence. microflowers and interpenetrative nanorods of CdS were formed...

We are the first to report a systematic study on the structural, optical and magnetic properties of cobalt and aluminum codoped CdS nanoparticles synthesized by simple co precipitation method. XRD patterns confirm the formation of single phase cubic structure for all the compositions. From diffuse reflectance spectra (DRS), three characteristic ref...

We are the first to report a systematic study on the structural, optical and magnetic properties of cobalt and aluminum codoped CdS nanoparticles synthesized by simple co precipitation method. XRD patterns confirm the formation of single phase cubic structure for all the compositions. From diffuse reflectance spectra (DRS), three characteristic ref...

Undoped and Co doped SnO 2 nanoparticles were synthesized by chemical co-precipitation method capped with PEG. The prepared particles were analyzed using X-ray diffraction (XRD), transmission electron microscopy (TEM), UV-Visible spectra. XRD patterns revealed that particles are crystallized in single phase rutile type tetragonal crystal structure...

Diluted magnetic semiconducting (DMS) ZnS:Ni (Ni=0, 1, 3 and 5 at%) nanoparticles were synthesized by the refluxing technique at 80 °C. X-ray diffraction studies showed that undoped ZnS and Ni doped ZnS nanoparticles exhibited the expected zinc blende structure. X-ray photoelectron spectroscopy results revealed that the Ni ions existed in a +2 stat...

CdS nanoparticles codoped with cobalt and manganese are synthesized by the surfactant assisted simple chemical coprecipitation method. Single cubic structure without any secondary phase formation is revealed by the XRD data. Small particle size around 4-5 nm is estimated from the TEM images. EPR hyperfine splitting constant A around 95 G associated...

Undoped and Cu doped CdS nanoparticles were synthesized in aqueous solution by chemical coprecipitation method using EDTA as a capping agent. As synthesized samples were characterized by X-ray diffraction (XRD), energy dispersive analysis of X-rays (EDAX), diffuse reflectance spectra (DRS). X-ray diffraction (XRD) analysis reveals that undoped CdS...

CdS:Mn (0%, 1.9% and 3%) nanowires with significant room-temperature ferromagnetism have been synthesized by chemical vapor deposition method using Au as catalyst. The X-ray diffraction, Raman spectroscopy and transmission electron microscopy analyses of these samples showed the formation of impurity free crystals with wurtzite CdS structure. SEM r...

ZnS:Co (0, 1, 2, 3 and 5 at.%) nanoparticles were synthesized by refluxing technique at 80 °C, with PVP as stabilizer. The effect of cobalt doping on the structural, optical and magnetic properties is investigated. EDAX spectra confirmed the presence of Zn, Co and S in the samples. X-ray diffraction patterns showed a single phase that of zincblende...

Undoped and Cr doped ZnS nanoparticles with Cr concentrations of 3.0 at.% were prepared by a chemical co-precipitation method for the fist time, using 2-Mercaptoethanol as the capping agent and annealed the synthesized particles at 600°C for 3h in air. The effect of annealing on morphological, structural and optical properties of ZnS and ZnS:Cr hav...

Nanocrystalline ZnS and Ni doped ZnS powders were synthesized by a simple chemical co-precipitation method at room temperature using sodium sulfide and acetates of Zinc and Nickel. 2-Mercapto ethanol is used as a capping agent. Structural and optical properties of as prepared samples were characterized using X-Ray diffraction (XRD), Scanning electr...

ZnS: Co (0 and 2 at.%) nanoparticles have been successfully synthesized through a simple chemical method namely refluxing technique using PVP as a stabilizer. The prepared samples have been characterized using X-ray diffraction (XRD), Diffusion reflectance spectra (DRS) and Photoluminescence studies (PL). XRD patterns of the nanoparticles showed...

One dimensional CdS nanostructures of different morphologies (nanowires, nanorods and nanobelts) and sizes were synthesized by a simple one step thermal evaporation of CdS powder using Au as catalyst. By controlling various experimental parameters such as temperature and position of the substrates in the furnace, different shapes of CdS nanostructu...