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Facile, one-step fabrication of durable, superhydrophobic (water contact angle ∼ 154 ∘) fluorine-free polymer coating on cotton cloth is presented. The microstructure of the coating is evaluated with electron microscopy and X-ray diffraction study. The detailed analysis reflects that the superhydrophobicity is rendered by intrinsic hydrophobic nature of the non-polar polymer, isotactic polypropylene. The chemical and mechanical stability of the coating on cloth is evaluated and it shows that the coating is extremely resilient in nature without almost negligible sacrifice in water contact angle. Because of simplicity of fabrication technique and quality of coating, this study is expected to be worthy enough for commodity as well as high technology applications. [ABSTRACT FROM AUTHOR]

We have shown that it is possible to realize multifunctional Bi1-xDyxFeO3 (BDFO) nanorods by coating BDFO film on ZnO nanorods. These BDFO coated ZnO (BDFO/ZnO) nanorods are obtained by depositing BDFO on vertical ZnO nanorods grown on Si substrate by using pulsed laser deposition technique. The BDFO/ZnO rods exhibit coexistence of ferroelectric and ferromagnetic properties with significant coupling between two order parameters at room temperature. Moreover, the piezoresponse of these nanorods is found to be even superior to pure ZnO nanorods. The unique multifunctional behavior of these nanorods at room temperature could find different applications in nanodevices like sensors, power generators, etc. with ease and flexibility in operation. [ABSTRACT FROM AUTHOR]

A variety of structurally heterogeneous nanostructured systems are known to exhibit nonlinear field emission characteristics (Fowler-Nordheim Plot). This behavior has earlier been ascribed to various reasons such as the emitter morphology or the state of aggregation of the individual components constituting the nanostructure. Here, we consider a random mesh of Cu 2 O nanorods as a model system, and investigate – both experimentally and analytically – the field emission from the sidewalls of this multi-layered nano-mesh. We show that the strongly non-linear emission characteristics (that is observed experimentally) can be simply and accurately simulated by summing over the emission from the successive layers of a model, multi-layer structure. The successive monolayers are shown to "turn on" at different values of applied voltage, naturally leading to a field-dependent enhancement factor. The non-linear field emission characteristics of a typical multi-layered emitter can be accurately simulated by considering the structure as a succession of layers and summing the contribution from each layer. For a fixed applied potential, V, the average electric field (E) at each layer is different, with E1>E2>E3, leading to a field-dependent emission. Image 1 • A simple, semi-quantitative model for the non-linear nature of the field emission characteristics. • Non-linear field emission of copper oxide nanorod-mesh. • Multi-layer structure is simply and accurately simulated using numerical as well as finite element analysis. [ABSTRACT FROM AUTHOR]

A superhydrophobic TiO 2 coating was prepared on mild steel to protect/increase life span of the steel by a simple one step electrophoretic deposition (EPD) technique followed by post-deposition treatment with methylhydrogen polysiloxane (trade name KF-99) and heat treatment. Superhydrophobicity was developed at some critical concentration (20 wt% solution) of KF-99. The water contact angle of bare steel, TiO 2 coated phosphated steel substrate (PSS) and TiO 2 coated PSS post treated with KF-99 (20 wt% solution) were 11°, 41.7° and 160.7°, respectively. The corrosion resistance of the superhydrophobic coating was estimated by Tafel polarization measurement. The potentiodynamic curves clearly demonstrated that the corrosion rate of superhydrophobic coating was an order of magnitude lower than bare mild steel in 3.5 wt% NaCl solution. The E corr and I corr values for the superhydrophobic TiO 2 PSS coating post treated with KF-99 were − 380 mV and 0.09 μA respectively, compared to − 930 mV and 120.22 μA for bare steel and − 820 mV and 20.41 μA for TiO 2 coated (PSS) untreated with KF-99. It clearly shows significant improvement in corrosion resistance properties of the superhydrophobic TiO 2 coated PSS. The coating also exhibited very strong adhesion to the surface with a nano-indentation hardness value of 0.5 GPa. The superhydrophobic coating with excellent corrosion resistance thus developed is a promising candidate for wide range of industrial applications. [ABSTRACT FROM AUTHOR]

A facile one-pot hydrothermal synthesis of hollow ball-like ZnS nanostructures is reported using cysteamine, an ecofriendly sulfur source. Following similar protocol, a heterostructure of RGO-ZnS nanocomposite have been synthesized. The as-synthesized samples are structurally and optically characterized using different techniques. The photocatalytic activity of RGO-ZnS has been found to be ∼9% higher than that of ball-like ZnS nanostructures at a dose of 0.4 g/L. This result is attributed to the improved charge transport by hindering charge recombination of photoinduced excitons. One of the significant findings of this work is that the model anionic dye degraded better under alkaline condition with ZnS whereas the trend is reversed for RGO-ZnS composite. The removal efficiency of both the systems is allied with structural, morphological, and optical properties to understand the underlying mechanism of synthesis as well as photocatalysis process. [ABSTRACT FROM AUTHOR]

Both n- and p-type single crystalline ZnO nanorods were successfully synthesized via a facile one step solvothermal method by lithium substitution. It was observed that substitution of Li is critical for the formation of n-type or p-type ZnO nanorods. The detailed formation mechanism indicates that the transition from n-type behavior to p-type behavior is due to the presence of defect states and lithium incorporation in the lattice. Using photoluminescence (PL) measurements, the role of defect states in generating the p-type or n-type nature of ZnO nanorods via Li substitution has been analyzed. Furthermore, the photocatalytic performances of the as-prepared ZnO nanorods have been investigated towards the degradation of rhodamine B and methyl orange, and the results demonstrate that the n-type ZnO nanorods behave as an excellent photocatalyst compared to the p-type ZnO nanorods owing to their higher charge carrier density. [ABSTRACT FROM AUTHOR]

In this work, we investigate growth of ordered arrays of amorphous TiO 2 nano-columns by using radio frequency sputter deposition technique. The as-prepared thin films were characterized by atomic force microscopy, field emission scanning electron microscopy, X-ray diffraction, and ultraviolet–visible spectroscopy. The nano-columnar films are found to be porous in nature which results from glancing angle sputter deposition. In fact, porosity has a linear relationship with increasing deposition angle. Reflectance of the thin films is also studied as a function of porosity. In addition, contact angle measurements demonstrate the roughness dependent transition from a hydrophilic to a hydrophobic TiO 2 surface. [ABSTRACT FROM AUTHOR]

Nanocomposite titanium-phosphate (TiP) of different sizes was synthesized using Triton X-100 (polyethylene glycol- p-isooctylphenyl ether) surfactant. The materials were characterized by FTIR and powdered X-ray diffraction (XRD). The structural and morphological details of the material were obtained by scanning electron microscopy (SEM) and transmission electron microscopy. The SEM study was followed by energy dispersive spectroscopic analysis for elemental analysis of the sample. The important peaks of the XRD spectra were analyzed to determine the probable composition of the material. The average size distribution of the particles was determined by dynamic light scattering method. Ion exchange capacity was measured for different metal ions with sizes of the TiP nanocomposite and size-dependent ion exchange property of the material was investigated thoroughly. The nanomaterial of the smallest size of around 43 nm was employed to separate carrier-free Ba from Cs in column chromatographic technique using 1.0 M HNO as eluting agent at pH 5. [ABSTRACT FROM AUTHOR]

We show that an aligned array of hydrothermally grown, multiwalled hydrogen titanate (H2Ti3O7) nanotubes—anchored to both faces of a metallic Ti foil—acts as an efficient photocatalyst. We studied the degradation of rhodamine B dye in the presence of the nanostructured photocatalyst under UV irradiation, by monitoring the optical absorption of the dye. Rhodamine B was chosen as a representative—and particularly harmful—industrial pollutant dye. The inner and outer diameters of the H2Ti3O7 nanotubes were 5nm and 10 nm, respectively. The nanotube array catalyst is recyclable and structurally stable. Most importantly, it shows comparable or higher photodecomposition rate constant than those of both H2Ti3O7 nanotube powder and P-25 (Degussa). The enhanced photocatalytic performance may be ascribed to the nanotube array having a superhydrophilic surface with a high accessible surface area. [ABSTRACT FROM AUTHOR]

Abstract: We report a simple, versatile, two-step fabrication technique for synthesizing a core–shell nanorod array whose architecture is specifically suited for use as an electrode in a dye sensitized solar cell (DSSC). The particular structure fabricated by us consists of a parallel array of 5μm long and 150–200nm wide Ag nanorod cores, each coated with a 15–20nm thick ZnO shell. Importantly, the shell thickness is roughly uniform throughout the length of the rods, which are free standing but distinctly separated from each other. This would allow the dye to penetrate freely and cover the ZnO surface completely in a DSSC. [ABSTRACT FROM AUTHOR]

Hydrothermally synthesized hydrogen titanate (H2Ti3O7) nanotube meshes and arrays exhibit excellent field emission characteristics. The turn-on field is as low as 1.4 V μm-1 for the mesh and 2.6 V μm-1 for the array, while the electric field corresponding to an emission current density of 10 μA cm-2 is 2 V μm-1 (mesh) and 3.8 V μm-1 (array). The H2Ti3O7 nanotube mesh has one of the lowest reported turn-on voltages and highest enhancement factors. The emission current also shows good long term stability. We attribute the efficient field emission to the presence of mid-gap states arising from the negative surface charge on the H2Ti3O7 nanotubes. [ABSTRACT FROM AUTHOR]

TiO 2 based nanostructures have been widely explored as photoanodes for dye-sensitized solar cells (DSSCs) because of their favourable band gap and corresponding compatibility with various sensitizers (dye molecules). Various morphologies and textures of titanium oxide have been thoroughly investigated to find the best efficiency in DSSCs. In this work, a detailed study of a nanocomposite of titanium dioxide partly derived from hydrogen titanate precursor has been reported. The current structure is realized in order to achieve optimal photogenerated charge carrier transport and reduced charge recombination. Among many combinations of the composites, the best photoanode showed power conversion efficiency (η) of 8.61% and corresponding open circuit voltage was 0.69 V and short circuit current 17.22 mA cm−2. The efficiency enhancement for the nanorod-nanoparticle composite photoanode is explained by structural, optical, and morphological properties and corroborated with electrochemical impedance spectroscopy. • TiO 2 -based nanorod-nanoparticle nanocomposite photoanode. • Maximum power conversion efficiency of 8.61%. • IPCE value with a maximum value of ∼64.6% at 525 nm. [ABSTRACT FROM AUTHOR]

Exploring porous heterojunction nanomaterials as a photocatalyst for water depollution strategies towards environmental restoration is exceedingly difficult in the perspective of sustainable chemistry. Herein, we first report a porous Cu–TiO 2 (TC40) heterojunction by using microphase separation of a novel penta-block copolymer (PLGA-PEO-PPO-PEO-PLGA) as a template through an evaporation induced self-assembly (EISA) method having nanorod-like particle shape. Furthermore, two types of photocatalyst were made with or without polymer template to clarify the function of that template precursor on the surface and morphology, as well as which variables are the most critical for a photocatalyst. TC40 heterojunction nanomaterial displayed higher BET surface area along with lower band gap value viz.2.98 eV compared to the other and these features make it a robust photocatalyst for wastewater treatment. In order to improve water quality, we have carried out experiments on the photodegradation of methyl orange (MO), highly toxic pollutants that cause health hazards and bioaccumulate in the environment. Our catalyst, TC40 exhibits the 100% photocatalytic efficiency towards MO dye degradation in 40 and 360 min at a rate constant of 0.104 ± 0.007 min−1 and 0.440 ± 0.03 h−1 under UV + Vis and visible light irradiation, respectively. [Display omitted] • Novel polymer template-driven interfacial structure affects the crystal architecture and photocatalytic efficiency. • TiO 2 /Cu 2 OCl 2 decomposes nearly 100% of methyl orange within 40 min and 6 h under UV and visible light, respectively. • The half-life times of methyl orange are 6.69 min and 1.6 h under UV and visible light, respectively. • Cu 2 OCl 2 crystal affects the photoactivity in the visible region. • Anatase TiO 2 crystal structure affects the overall photocatalytic efficiency. [ABSTRACT FROM AUTHOR]

Ceria–titania doped highly ordered hexagonal and cubic mesoporous silica composite samples with varying amounts of Ce and Ti have been synthesized using hexadecyltrimethylammonium bromide (CTAB) surfactant as a template under basic conditions in the presence of ammonia. The removal of the template resulted in the formation of mesoporous composites doped with Ce and Ti, which were thoroughly characterized via small-angle X-ray scattering (SAXS), wide-angle X-ray diffraction (WAXRD), N2 adsorption, scanning and transmission electron microscopy analysis with energy-dispersive spectrometry mapping (SEM-TEM-EDS), inductively coupled plasma atomic emission spectrophotometry (ICP-AES), and ultraviolet-visible diffuse reflectance spectrometry (UV-visible). The electronic states of Ti and Ce species present on the surface of silica were also investigated by X-ray photoelectron spectroscopy (XPS). The catalytic activity of these Ti-modified ceria–silica samples for the photodecomposition of rhodamine B under visible-light irradiation was investigated. The results revealed that a sample with a higher Ti content, as well as equal amounts of Ce and Ti, displayed higher catalytic activity for the photodegradation of the organic dye rhodamine B. [ABSTRACT FROM AUTHOR]

H 2 and CO 2 adsorption was investigated using pristine hydrogen titanate nanotube (HTNT) and nanorod (HTNR). HTNT and HTNR were modified with N-[3-(trimethoxysilyl)propyl]ethylene-diamine (TPEDA). Chemical linkage between an amine-containing organosilane and titanium on the surface of hydrogen titanate was confirmed with 29 Si CP-MAS NMR spectrum. H 2 and CO 2 uptake on several hydrogen titanate samples was obtained by a TGA Q50 analyzer in flowing N 2 gas of 40 mL/min and CO 2 gas of 60 mL/min at 25 °C and 1 atm. Pristine HTNT sample showed the highest H 2 uptake (i.e. ∼12.5 mmol/g) on a TGA microbalance at 25 °C whereas amine-modified HTNT sample exhibited the highest CO 2 uptake (i.e. ∼1.2 mmol/g) among all samples studied. CO 2 /N 2 and H 2 /N 2 selectivity for pristine and amine-modified HTNT samples was investigated by comparing the weight of the sample in flowing pure N 2 gas of 100 mL/min with above-mentioned mixed flows at 25 °C. Reversibility for CO 2 and H 2 uptake showed good performance for 9 cycles. [ABSTRACT FROM AUTHOR]

A galaxy of new two‐dimensional (2D) transition metal carbides, nitrides, and carbonitrides (MXenes) have outperformed other 2D nanomaterials in numerous promising applications due to their extraordinary properties. However, the synthesis of MAX phase is pertinent as it is the only precursor for the development of 2D MXenes. As many conventional MAX phase synthesis procedures are complex, time‐ and power consuming, we have introduced a novel electric‐field‐assisted flash sintering technique for a rapid synthesis of Ti3SiC2 MAX phase in both air and vacuum, facilitated by Joule heating effect. The flashing event was observed with an uncontrollable rise in current flow (∼255 mA/mm2) on the application of voltage in a range of 35–42 V/cm. Experimental outcome predicted that Ti3SiC2 MAX phase was synthesized by applying an electric field. Here we support the experimental findings through computational approach by using density functional theory calculations. We also report the synthesis of 2D Ti3C2TX MXene from flash‐synthesized Ti3SiC2 MAX phase. The scientific innovation discussed here could be a breakthrough in the rapid synthesis of different MAX phases with great potential for implementation in industrial scale. [ABSTRACT FROM AUTHOR]

We report a simple, solution-based technique for coating arbitrary surfaces with thin layers of self-assembled copper tetradecanoate (CTD) nanostrips, resulting in an optically transparent, superhydrophobic coating. The nanostrip-coated surfaces show water contact angles close to 150° and roll-off angles as small as 2°-3°. Importantly, CTD retains its hydrophobic nature even after annealing the self-assembled nanostrips at 200°C, which does not alter the crystal structure but “melts” the surface microstructure. This clearly indicates that the hydrophobicity in CTD is likely to be intrinsic in nature and not induced by the surface microstructure (as has been suggested earlier). Strong hydrophobicity in CTD over a relatively wide temperature range presumably results from the presence of the long aliphatic (tetradecanoate) chains in its structure. Importantly, the self-assembled copper tetradecanoate nanostrips can be dip-coated on glass to render it hydrophobic and at the same time retain a significant level of transparency over the entire visible region. Such nanostructured thin films may be expected to find applications not only as a self-cleaning glass, but also as a corrosion resistant coating, in gas storage (due to the layered structure), and as an active catalyst because of the visible absorbance. [ABSTRACT FROM AUTHOR]

The scientific enterprise in India has grown dramatically in the past few decades, with research emerging as a viable and important career option for students of science. The country thus has a large population of young scientists in the early stages of establishing their independent research careers. While this demographic is arguably the most important group that will determine the future of scientific research in India, their status and concerns are poorly understood. The Indian National Young Academy of Sciences conducted a national survey to better understand and present the challenges faced by them. Through a structured questionnaire, we sought the views of researchers below 45 years of age. Here, we summarize the responses from 854 participants across multiple early career stages. We highlight key challenges faced by these scientists in establishing an independent research career, and suggest steps to address them. [ABSTRACT FROM AUTHOR]

We demonstrate how the morphology of a simple metal-oxide system (e.g., Cu2O) controls catalytic activity. Cu2O catalysts were synthesized with a highly uniform nanocube and nano-octahedra morphology under PVP surfactant-assisted reaction conditions. A series of structural, morphological, optical and electrical characterizations are done to optimize the growth of nanostructures with different morphologies. Finally, the nanostructures are exploited as photo- and electrocatalysts. Interestingly, we find dissimilitude behaviour of nano-octahedra and nano-cube samples towards photo and electrocatalytic activities. The nano-octahedra samples are ∼57% more photocatalytically active (half-life timeoctahedra∼ 10.7 minutes) than the nanocube samples, which is one of the highest reported photocatalytic efficiencies reported to date. However, the same nano-octahedra samples show lower electrocatalytic activity towards oxygen reduction reaction (ORR) as compared with the nanocube sample. [ABSTRACT FROM AUTHOR]

Multi-walled carbon nanotubes (MWCNT) having diameter in the range of 5–30 nm were coated on silicon wafer using spray coating technique. The coated film was irradiated with 5 keV Na + at a fluence of 1 × 10 16  ions·cm −2 . A large-scale welding is observed in the post-irradiated nanotube assembly under scanning electron microscope. We have studied dynamic wetting properties of the nanotubes. While the pristine MWCNT shows superhydrophobic nature, the irradiated MWCNT turns into hydrophilic. Our simulation based on iradina and experimental evidences show defect formation in MWCNT due to ion irradiation. We have invoked mechanism based on defect mediated adsorption of water, which plays major role for transition from superhydrophobic to hydrophilic. [ABSTRACT FROM AUTHOR]

Well-dispersed single phasic flower-like zero valent iron nanoparticles have been synthesized under aerobic conditions using a facile approach without the addition of any additives or templates. The role of hydroxyl groups of polyhydroxy alcohols in controlling surface morphology of nanoparticles has been thoroughly investigated. The obtained nanoparticles have been characterized by TEM, FE-SEM, XRD and BET surface area analyzer. Electron microscopy analyses reveal that the solvent plays a pivotal role in determining the morphology of the particles. With increase in viscosity of the solvent, formations of ‘petal-like’ structures, which are joined at the center are formed. The nitrate removal efficiency of the iron nanoparticles synthesized in different solvents has been studied and it is seen that the “flower-like” iron nanoparticles were most active in the removal of nitrate. Experiments have been done by varying (i) nitrate concentrations, (ii) nanoparticle dose, and (iii) type of nanoparticles. The results conclude that highest removal efficiency (∼100%) was achieved when the nanoparticle dose was 2.88 g/L, even for high nitrate concentrations up to 400 mg/L. The major highlight of this work is the fact that even though the nanoparticles synthesized in glycerol-water mixture have larger size in comparison to the other nanoparticles, still they remove the nitrates with highest efficiency.” [ABSTRACT FROM AUTHOR]

Abstract: The visible light photocatalytic degradation of a synthetic oral contraceptive, 17α‐ ethinylestradiol (EE2) and a natural estrogen, estrone (E1) by Cu2O nanostructures has been investigated. For this purpose, Cu2O nanocrystals with varied morphologies (nano‐ cubes, nano‐ octahedra and nano‐ rods) have been synthesized via different synthetic routes. The morphological evolution from nano‐ cubes to nano‐ octahedra with simple alteration of the stabilizing agent (PVP) has been shown. To account for the pH effect on the degradation rates, the photocatalytic experiments have been conducted in three different pH values (7, 8 and 10). Photocatalytic studies prove that the Cu2O nanostructures work best at pH 7 with decrease in efficiency at higher pH. Cu2O nano‐ rods has emerged as the best visible light photocatalyst at pH 7 (95 % degradation within 45 minutes of irradiation) reported till date for the degradation of estrogens EE2 and E1. [ABSTRACT FROM AUTHOR]

We report the role of pressure dependent growth of micro and nanorod arrays of zinc oxide by an aqueous solution route. Initially, both micro- and nano-ZnO surfaces show hydrophobicity with water contact angles of 140°± 3° and 130°± 3°, respectively. We find that the temporal decay in water contact angle is faster in the case of the nanorod surface compared to that of the microrod surface. While for the microrod surface, the small change in contact angle happens due to water droplet evaporation, the significant change in the particular case of the nanorod surface is attributed to the capillary action. [ABSTRACT FROM AUTHOR]