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Grain boundary complexion modification for interface stability in garnet based solid-state Li batteries
No full textThe garnet type solid-state electrolyte (SSE) encounters challenges related to poor interfacial contact with Li metal and dendrite penetration problem. This study addresses these issues by manipulating the surface property of garnet-based LLZTO (Li6.5La3Zr1.6Ta0.4O12) SSE. The manipulation is achieved by varying thickness of Al2O3 atomic layer deposition (ALD), followed by sintering. Research results show that the relative density, ionic conductivity, and hardness of LLZTO are improved while electronic conductivity is reduced due to the formation of multiple complexions at grain boundary (GB). The SSE pellets also demonstrate improved wettability with Li metal, leading to stable galvanostatic Li plating/stripping cycling with low polarization, which allows for batter battery performance than pristine one. The concept of modifying SSE through the grain boundary complexion modification by thin ALD coating for enhancing the dendrite tolerance with better electrochemical properties of SSE may open a new direction for solid state battery research
Advances in GeSn alloys for MIR applications
No full textSilicon photonics is widely used for near InfraRed (IR) applications up to 1.6 µm. It plays a key role in short-range optical data communications. However, silicon photonics does not really address mid-IR applications, particularly in the 1.6–5 µm wavelength range. This spectral region is essential for environmental/life sensing and safety applications relying on the optical features of molecular vibrations, the aim being to discern and categorize complex chemical entities. Growing markets for such analysis prioritise sensitivity, specificity, compactness, energy-efficient operation and cost effectiveness. The need for a CMOS-compatible integrated photonic platform for the mid-IR is obvious. Such fully-group-IV semiconductor platform should include low-loss guided interconnects, detectors, modulators and, critically, efficient integrated light sources. This paper provides a comprehensive review of recent advances in GeSn-based mid-IR silicon-compatible devices, including optically and electrically pumped lasers, light-emitting diodes and photodetectors. It also discusses the principles underlying these developments, with focuses on material growth techniques and processing methods
Biochar pH reduction using elemental sulfur and biological activation using compost or vermicompost
No full textAn efficient ALD- and noble metal-free charge recombination architecture for monolithic all-perovskite tandem solar cells
No full textThe currently efficient all-perovskite tandem solar cells (all-PTSCs) are built on the workhorse charge recombination layers (CRLs) composed of ALD-SnOX/noble metal/PEDOT:PSS. However, the susceptibility of optoelectronic properties of SnOX to atomic growth conditions and the use of rare metals constrain their promise for commercial deployment. Here, we design an efficient and robust CRL consisting of a layer sequence of Cr/ITO/PEDOT:PSS. The conformally grown thin Cr layer serves as a critical barrier to protect the underlying perovskite from damage during ITO sputtering. Essentially, the entire stack of the CRL exhibits superior resistance to strong polar solvents during the deposition of top narrow-bandgap perovskites. On this basis, high-performance monolithic all-PTSCs are reproducibly fabricated, yielding a state-of-the-art efficiency of 26.56%, alongside an impressive fill factor (FF) of 80.6%
3D-manufactured non-isothermal glass cell for thermophoretic measurements
No full textThermophoresis, the migration of particles within a thermal gradient, presents opportunities in diverse fields ranging from biotechnology to energy applications. The quantification of this phenomenon, described by the Soret coefficient (S_T), requires precise control over non-isothermal conditions, which is challenging to achieve in conventional microfluidic devices. However, conventional polymer-based cells are limited by a significant temperature drop across the material and susceptibility to the adhesion of colloidal particles. Recently, 3D-manufactured glass cells have been shown to produce a non-isothermal temperature field in a microchannel for inducing a significant temperature gradient due to high thermal conductivity, which enables temperature-dependent analysis of thermophoresis. Herein, we present a 3D-manufactured glass microfluidic cell for measuring the Soret coefficient under controlled temperature gradients. The cell produces a stable and a large temperature gradient across the channel which allows multi-temperature measurements without adjusting hot and cold water temperatures. The measured Soret coefficient by the glass cell across a temperature range of 20 °C to 30 °C shows close agreement with the benchmark measurement data. These results show that the 3D-manufactured glass cell can not only quantify the Soret coefficient but can also function as a solvent-resistant device, suitable for complex biological and chemical solutions
Proton Ordering Induces a Polar Structure in the Antiferromagnetic Solid Proton Conductor
No full textMaterials exhibiting coexisting exploitable properties often result in especially attractive behavior from both fundamental and applied perspectives. In particular, magnetoelectric materials combining ferroelectric and magnetic properties are increasingly becoming paramount nowadays. Here, we show that exhibits proton conductivity and the coexistence of magnetic and polar structural features, suggesting that such frameworks may be of broader interest beyond the field of proton conductors. By a combination of neutron diffraction and second harmonic generation experiments, we have demonstrated that crystallizes in the polar space group. Inversion symmetry breaking is triggered by a polar proton ordering within the structure. In , this particular cation ordering in combination with the polar displacement of the adjacent structural units results in a polar crystal structure with a calculated net polarization of approximatel between 10 and 300 K. Together with an antiferromagnetic state below 28 K, determined from a combination of neutron diffraction and magnetic measurements and associated with the particular octahedral arrangement, the result is the coexistence of both properties. By a detailed study of this system with a full description of the crystal structure as well as the ionic and magnetic properties, we aim to spark further investigations in magnetoelectric materials existing in the solid ionic conductor phase space
Synthesis and Biological Evaluation of Nipecotic Acid Derivatives with Terminally Double-Substituted Allenic Spacers as mGAT4 Inhibitors
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