High-Performance Printed AgSe/PI Flexible Thermoelectric Film for Powering Wearable Electronics.

We report the magnificent thermoelectric properties of the n-type AgSe film printed onto a flexible polyimide (PI) substrate. The orthorhombic β-AgSe phase of the processed AgSe film is confirmed from the X-ray diffractogram. Remarkably, the resulting AgSe/PI film exhibits outstanding thermoelectric properties, boasting maximum power factors of 1.

Enhancement in Thermoelectric Performance in Ti-doped YbCoSb Skutterudites via Carrier Optimization and Phonon Anharmonicity.

YbCoSb, being a well-studied system, has shown notably high thermoelectric performance due to the Yb filler atom-driven large concentration of charge carriers and lower value of thermal conductivity. In this work, the thermoelectric performance of YbCoTiSb (where = 0, = 0 and = 0.4, = 0, 0.

Lanthanide(III) (Er/Ho) coordination polymers for a photocatalytic CO cycloaddition reaction.

Two new isostructural carboxylate-bridged lanthanide ribbons having the chemical formula [Ln(4-ABA)] [4-ABA = 4-aminobenzoate, Ln: holmium (Ho) and erbium (Er)] were synthesized by a solvothermal method and fully characterized using multiple analytical, spectroscopic, and computational techniques. Single-crystal X-ray diffraction analysis reveals that both lanthanide coordination polymers (Ln-CPs) exhibit linear ribbon-like structures built up by dinuclear Ln(4-ABA) units and bridged by carboxylate groups. Ln-CPs showed remarkably high thermal and chemical stabilities.

A new mode of luminescence in lanthanide oxalates metal-organic frameworks.

Two lanthanide metal-organic frameworks [Ln-MOFs, Ln = Eu(III), Tb(III)] composed of oxalic acid and Ln building units were hydrothermally synthesized and fully characterized by powder X-ray diffraction, Fourier-transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscope, and energy-dispersive X-ray spectroscopy. Furthermore, their magnetic susceptibility measurements were obtained using SQUID based vibrating sample magnetometer (MPMS 3, Quantum Design). Both Ln-MOFs exhibited highly efficient luminescent property.

Thermoelectric properties of Ag-doped CuI: a temperature dependent optical phonon study.

Due to the natural abundance and non-toxicity of copper (Cu) and iodine (I), γ-CuI has been widely explored as a potential transparent thermoelectric material for near room temperature applications. Here, we report the effect of doping of an heavy atom such as silver (Ag) on the evolution of temperature-dependent optical phonon modes and thermoelectric properties of chemically synthesized single-phase nanocrystalline γ-CuI. We found that Ag doping reduces the lattice parameters of CuI and thereby confirms the occupancy of Ag atoms at the vacancy sites of CuI.

Study of Thermometry in Two-Dimensional SbTe from Temperature-Dependent Raman Spectroscopy.

Discovery of two-dimensional (2D) topological insulators (TIs) demonstrates tremendous potential in the field of thermoelectric since the last decade. Here, we have synthesized 2D TI, SbTe of various thicknesses in the range 65-400 nm using mechanical exfoliation and studied temperature coefficient in the range 100-300 K using micro-Raman spectroscopy. The temperature dependence of the peak position and line width of phonon modes have been analyzed to determine the temperature coefficient, which is found to be in the order of 10 cm/K, and it decreases with a decrease in SbTe thickness.

Spin reorientation in antiferromagnetic DyFeCoO double perovskite.

We explored the electronic and magnetic properties of the lanthanide double perovskite DyFeCoO by combining magnetization, Raman and Mössbauer spectroscopy and neutron diffraction along with density functional theory (DFT) calculations. Our magnetization measurements revealed two magnetic phase transitions in DyFeCoO. First, a paramagnetic to antiferromagnetic transition at T = 248 K and subsequently, a spin reorientation transition at T = 86 K.

Probing the Griffiths like phase, unconventional dual glassy states, giant exchange bias effects and its correlation with its electronic structure in Pr Sr CoMnO.

Crystal, electronic structure, dc and ac magnetization properties of the hole substituted (Sr) and partially B-site disordered double perovskite Pr Sr CoMnO system have been investigated. The XRD pattern analysis showed a systematic decrease in the lattice parameters owing to the enhanced oxidation states of the Co/Mn ions. The electronic structure study by XPS measurements suggested the presence of mixed valence states of the B-site ions (Co /Co and Mn /Mn) with significant enhancement of the average oxidation states due to hole doping.

Spin reorientation and disordered rare earth magnetism in HoFeCoO.

We report the experimental observation of spin reorientation in the double perovskite HoFeCoO. The magnetic phase transitions in this compound are characterized and studied through magnetization and specific heat, and the magnetic structures are elucidated through neutron powder diffraction. Two magnetic phase transitions are observed in this compound-one at [Formula: see text] K, from paramagnetic to antiferromagnetic, and the other at [Formula: see text] K, from a phase with mixed magnetic structures to a single phase through a spin reorientation process.

Magnetic glass state and magnetoresistance in SrLaFeCoO double perovskite.

Unusual features in magnetization resembling the kinetic arrest of a magnetic glass state are observed in the La-doped double perovskite, SrLaFeCoO. Neutron powder diffraction experiments confirm the presence of antisite disorder as well as a lack of long-range magnetic order down to 4 K in this double perovskite which displays spin glass-like features in dc and ac susceptibilities. Magnetic relaxation observed through cooling and heating under unequal fields (CHUF) point towards unusual domain dynamics which is supported by a broad memory effect.

Hydrogen storage studies of palladium decorated nitrogen doped graphene nanoplatelets.

Hydrogen storage in materials is of significant importance in the present scenario of depleting conventional energy sources. Porous solids such as activated carbon or nanostructured carbon materials have promising future as hydrogen storage media. The hydrogen storage capacity in nanostructured carbon materials can be further enhanced by atomic hydrogen spillover from a supported catalyst.

Magnetic and magnetocaloric properties of nanocrystalline Pr(1-x)A(x)Mn(1-y)Co(y)O3 (A = Ca, Sr) (x = 0.3; y = 0.5) manganites.

Structural, magnetic and magnetocaloric properties of sol-gel prepared, nanocrystalline oxides Pr(1-x)A(x)Mn(1-y)Co(y)O3 (A = Ca, Sr) (x = 0.3; y = 0.5) (cubic, space group Fm3m) have been studied.

A glucose biosensor based on deposition of glucose oxidase onto crystalline gold nanoparticle modified carbon nanotube electrode.

A new amperometric biosensor, based on deposition of glucose oxidase (GOD) onto crystalline gold (Au) nanoparticle modified multiwalled carbon nanotube (MWNT) electrode, is presented. MWNTs have been synthesized by catalytic chemical vapor decomposition of acetylene over rare-earth-based AB2 (DyNi2) alloy hydride catalyst. Purified MWNTs have been decorated with nanocrystalline Au metal clusters using a simple chemical reduction method.

Effect of Purity and Substrate on Field Emission Properties of Multi-walled Carbon Nanotubes.

Multi-walled carbon nanotubes (MWNT) have been synthesized by chemical vapour decomposition (CVD) of acetylene over Rare Earth (RE) based AB2(DyNi2) alloy hydride catalyst. The as-grown carbon nanotubes were purified by acid and heat treatments and characterized using powder X-ray diffraction, Scanning Electron Microscopy, Transmission Electron Microscopy, Thermo Gravimetric Analysis and Raman Spectroscopy. Fully carbon based field emitters have been fabricated by spin coating a solutions of both as-grown and purified MWNT and dichloro ethane (DCE) over carbon paper with and without graphitized layer.