Screen printed flexible Bi2Te3-Sb2Te3 based thermoelectric generator

This paper reports the fabrication and testing of Bismuth Tellurium (Bi2Te3) – Antimony Tellurium (Sb2Te3) based thermocouples using screen printing technology. In this study, screen printable thermoelectric pastes were developed and the transport properties of cured material were measured. The dimension of each planer thermoleg is 39.3 mm × 3 mm with a thickness of 67 µm for Bi2Te3 leg and 62 µm for Sb2Te3 leg. A single thermocouple with this dimension can generate a voltage of 6 mV and a peak output power of 48 nW at a temperature difference of 20°C. The calculated Seebeck coefficient of a single thermocouple is in the range of 262 to 282 µV/K. The Seebeck coefficient at room temperature were measured to be -134 to -119 µV/K and 128 to 134 µV/K for Bi2Te3 and Sb2Te3 respectively. This work demonstrates that the low-cost screen printing technology and low-temperature materials are promising for the fabrication of flexible thermoelectric generators (TEGs)

Laser-induced forward transfer of thermoelectric materials on polymer and glass substrates

Laser-induced forward transfer (LIFT) is a laser-assisted direct write method that has been used to print a range of solids and rheological fluids. The donor that is to be printed is previously deposited onto a transparent support substrate that is usually referred to as a carrier. A highly energetic short-pulsed laser beam imaged through the transparent carrier onto the donor results in the forward transfer of a donor pixel onto a receiver substrate placed either in contact or a few microns apart. Solid films can be transferred with minimal change in their crystal and domain structure via LIFT

Nanostructured thermoelectric generator for energy harvesting

This paper presents the development processes towards a new generation of nanostructured thermoelectric generators for power harvesting from small temperature gradients by using a combination of traditional silicon microfabrication techniques, electroplating and submicron ion-track nanolithography. Polyimide nanotemplates with pore diameters ranging from 30nm to 120 nm were fabricated. Preliminary results for Bi2Te3 nanowires (50 and 120 nm diameter) electroplated into polycarbonate ion-track commercial membranes are presented. Bi2Te3 nanowires of R ̄ 3m structure, with preferential orientation in the (015) and (110) crystallographic plans with nearly stoichiometric composition were electroplated. The fine-grained observed microstructure (6-10 nm) and (110) crystalline orientation appear extremely promising for improving thermoelectric material properties

Fabrication of micromirrors with pyramidal shape using anisotropic etching of silicon

Gold micro-mirrors have been formed in silicon in an inverted pyramidal shape. The pyramidal structures are created in the (100) surface of a silicon wafer by anisotropic etching in potassium hydroxide. High quality micro-mirrors are then formed by sputtering gold onto the smooth silicon (111) faces of the pyramids. These mirrors show great promise as high quality optical devices suitable for integration into MOEMS systems

Влияние преобразователей частоты на изоляцию силовых кабелей нефтедобывающих станций

The paper considers consequences of negative frequency converter influence on insulation of  power supply cables used for submersible installations of electric-centrifugal pumps at oil-producing stations. The possible approaches to the solution of the problem are proposed on the basis of a harmonic analysis of actually measured voltages and currents in a cable.  Рассмотрены последствия негативного влияния преобразователей частоты на изоляцию силовых кабелей, питающих погружные установки электроцентробежных насосов нефтедобывающих станций. На основе гармонического анализа реально измеренных напряжений и токов в кабеле предложены возможные пути для решения этой проблемы

Electrochemical deposition of bismuth telluride thick layers onto nickel

Bismuth telluride (Bi2Te3) is the currently best performing thermoelectric (TE) material in commercial TE devices for refrigeration and waste heat recovery up to 200 °C. Up to 800 μm thick, compact, uniform and stoichiometric Bi2Te3 films were synthesized by pulsed electrodeposition from 2 M nitric acid baths containing bismuth and tellurium dioxide on 1 cm2 nickel (Ni) substrates at average film growth rates of ~ 50 μm/h. Pre-treatment of the Ni substrate was found to significantly enhance the adhesion of Bi2Te3 material onto Ni while pulsed electrodeposition was used to increase the compactness of the material. To maintain a homogeneous composition across the thickness of the films, a sacrificial Bi2Te3 anode was employed. All deposits produced were n-type with a Seebeck coefficient of up to − 80 μV/K and an electrical conductivity of ~ 330 S/cm at room temperature

Performance limits of the three MEMS inertial energy generator transduction types

Accepted versio

Thermoelectric generator fabricated via laser-induced forward transfer

We show a novel method for the fabrication of a thermoelectric generator with the rapid, lithography-less technique of laser-induced forward transfer (LIFT), performed under ambient conditions. LIFT is a laser-assisted method for the transfer of materials such as metals, semiconductors and dielectrics, where a part of a thin film (donor) previously coated onto a transparent carrier substrate is transferred onto a nearby receiver initiated by the explosive expansion of a small part of the donor volume after the absorption of a laser pulse [1]. Electronic or photonic devices can be fabricated via LIFT on a range of receiver substrates, free from any constraints of substrate properties such as lattice constant or thermal expansion coefficient. This flexibility is desired for applications such as rapid prototyping and the fabrication of devices joining multiple non-standard materials on one substrate. The design of the proposed thermoelectric generator was selected to demonstrate the capabilities of LIFT by transferring layers from the chalcogenide compounds of Bi2Te3 and Bi0.5Sb1.5Te3 onto a glass receiver coated with a polydimethylsiloxane (PDMS) polymer