High Figure-of-Merit Telluride-Based Flexible Thermoelectric Films through Interfacial Modification via Millisecond Photonic-Curing for Fully Printed Thermoelectric Generators.

The thermoelectric generator (TEG) shows great promise for energy harvesting and waste heat recovery applications. Cost barriers for this technology could be overcome by using printing technologies. However, the development of thermoelectric (TE) materials that combine printability, high-efficiency, and mechanical flexibility is a serious challenge.

A multipurpose laboratory diffractometer for powder X-ray diffraction investigations of energy materials.

Laboratory X-ray diffractometers are among the most widespread instruments in research laboratories around the world and are commercially available in different configurations and setups from various manufacturers. Advances in detector technology and X-ray sources push the data quality of in-house diffractometers and enable the collection of time-resolved scattering data during experiments. Here, the design and installation of a custom-built multipurpose laboratory diffractometer for the crystallographic characterization of battery materials are reported.

Photonic Curing Enables Ultrarapid Processing of Highly Conducting β-CuSe Printed Thermoelectric Films in Less Than 10 ms.

It has been a challenge to obtain high electrical conductivity in inorganic printed thermoelectric (TE) films due to their high interfacial resistance. In this work, we report a facile synthesis process of Cu-Se-based printable ink for screen printing. A highly conducting TE β-CuSe phase forms in the screen-printed Cu-Se-based film through ≤10 ms sintering using photonic-curing technology, minimizing the interfacial resistance.

Realizing High Thermoelectric Performance of Bi-Sb-Te-Based Printed Films through Grain Interface Modification by an In Situ-Grown β-CuSe Phase.

It has been a substantial challenge to develop a printed thermoelectric (TE) material with a figure-of-merit > 1. In this work, high p-type BiSbTe-based printable TE materials have been advanced by interface modification of the TE grains with a nonstoichiometric β-CuSe-based inorganic binder (IB) through a facile printing-sintering process. As a result, a very high TE power factor of ∼17.

Creating a Ferromagnetic Ground State with T Above Room Temperature in a Paramagnetic Alloy through Non-Equilibrium Nanostructuring.

Materials with strong magnetostructural coupling have complex energy landscapes featuring multiple local ground states, thus making it possible to switch among distinct magnetic-electronic properties. However, these energy minima are rarely accessible by a mere application of an external stimuli to the system in equilibrium state. A ferromagnetic ground state, with T above room temperature, can be created in an initially paramagnetic alloy by nonequilibrium nanostructuring.

Magnetoelectric Tuning of Pinning-Type Permanent Magnets through Atomic-Scale Engineering of Grain Boundaries.

Pinning-type magnets with high coercivity at high temperatures are at the core of thriving clean-energy technologies. Among these, Sm Co -based magnets are excellent candidates owing to their high-temperature stability. However, despite intensive efforts to optimize the intragranular microstructure, the coercivity currently only reaches 20-30% of the theoretical limits.

Giant voltage-induced modification of magnetism in micron-scale ferromagnetic metals by hydrogen charging.

Owing to electric-field screening, the modification of magnetic properties in ferromagnetic metals by applying small voltages is restricted to a few atomic layers at the surface of metals. Bulk metallic systems usually do not exhibit any magneto-electric effect. Here, we report that the magnetic properties of micron-scale ferromagnetic metals can be modulated substantially through electrochemically-controlled insertion and extraction of hydrogen atoms in metal structure.

High-Performance Ag-Se-Based n-Type Printed Thermoelectric Materials for High Power Density Folded Generators.

High-performance Ag-Se-based n-type printed thermoelectric (TE) materials suitable for room-temperature applications have been developed through a new and facile synthesis approach. A high magnitude of the Seebeck coefficient up to 220 μV K and a TE power factor larger than 500 μW m K for an n-type printed film are achieved. A high figure-of-merit ∼0.

Design and Tuning of the Electrochemical Properties of Vanadium-Based Cation-Disordered Rock-Salt Oxide Positive Electrode Material for Lithium-Ion Batteries.

Disordered rock-salt compounds are becoming increasingly important due to their potential as high-capacity positive electrode materials for lithium-ion batteries. Thereby, a significant number of studies have focused on increasing the accessible Li capacity, but studies to manipulate the electrochemical potential are limited. This work explores the effect of transition-metal substitution on the electrochemistry of ternary disordered rock-salt-type compounds with LiMVO stoichiometry (M = Mn, Fe, Co) directly synthesized through mechanochemistry.

In operando study of the high voltage spinel cathode material LiNi(0.5)Mn(1.5)O4 using two dimensional full-field spectroscopic imaging of Ni and Mn.

LiNi0.5Mn1.5O4 spinel cathode was studied during the first discharge cycle using combined full field Transmission X-ray Microscopy (TXM) and X-ray Absorption Near Edge Structure Spectroscopy (XANES) techniques to follow the chemical phase transformation as well as the microstructural evolution of cathode materials upon operation within an electrochemical cell.

Chemical and electrochemical insertion of Li into the spinel structure of CuCr2Se4: ex situ and in situ observations by X-ray diffraction and scanning electron microscopy.

The chemical and electrochemical insertion of lithium into the spinel structure of CuCr(2)Se(4) was studied and the chemical reaction pathway was followed by ex situ X-ray diffraction on samples with different Li contents. The electrochemical reaction was investigated by in situ X-ray diffraction and in situ scanning electron microscopy. In the early steps of chemical intercalation, two phases with a different Li content coexist and Cu is extruded from the host material.