King Abdullah University of Science and Technology

About: King Abdullah University of Science and Technology is a education organization based out in Jeddah, Saudi Arabia. It is known for research contribution in the topics: Catalysis & Membrane. The organization has 6221 authors who have published 22019 publications receiving 625706 citations. The organization is also known as: KAUST.

Zinc-ion batteries: Materials, mechanisms, and applications

Abstract: The increasing global demand for energy and the potential environmental impact of increased energy consumption require greener, safer, and more cost-efficient energy storage technologies. Lithium-ion batteries (LIBs) have been successful in meeting much of today’s energy storage demand; however, lithium (Li) is a costly metal, is unevenly distributed around the world, and poses serious safety and environmental concerns. Alternate battery technologies should thus be developed. Zinc-ion batteries (ZIBs) have recently attracted attention due to their safety, environmental friendliness, and lower cost, compared to LIBs. They use aqueous electrolytes, which give them an advantage over multivalent ion batteries (e.g., Mg2+, Ca2+, Al3+) that require more complex electrolytes. However, as with every new technology, many fundamental and practical challenges must be overcome for ZIBs to become commercial products. In this manuscript, we present a timely review and offer perspectives on recent developments and future directions in ZIBs research. The review is divided into five parts: (i) cathode material development, including an understanding of their reaction mechanism; (ii) electrolyte development and characterization; (iii) zinc anode, current collector, and separator design; (iv) applications; and (v) outlook and perspective.

Hybrid organic–inorganic inks flatten the energy landscape in colloidal quantum dot solids

Abstract: Bandtail states in disordered semiconductor materials result in losses in open-circuit voltage (Voc) and inhibit carrier transport in photovoltaics. For colloidal quantum dot (CQD) films that promise low-cost, large-area, air-stable photovoltaics, bandtails are determined by CQD synthetic polydispersity and inhomogeneous aggregation during the ligand-exchange process. Here we introduce a new method for the synthesis of solution-phase ligand-exchanged CQD inks that enable a flat energy landscape and an advantageously high packing density. In the solid state, these materials exhibit a sharper bandtail and reduced energy funnelling compared with the previous best CQD thin films for photovoltaics. Consequently, we demonstrate solar cells with higher Voc and more efficient charge injection into the electron acceptor, allowing the use of a closer-to-optimum bandgap to absorb more light. These enable the fabrication of CQD solar cells made via a solution-phase ligand exchange, with a certified power conversion efficiency of 11.28%. The devices are stable when stored in air, unencapsulated, for over 1,000 h.

Genome-wide association study identifies eight risk loci and implicates metabo-psychiatric origins for anorexia nervosa

Abstract: Characterized primarily by a low body-mass index, anorexia nervosa is a complex and serious illness1, affecting 0.9-4% of women and 0.3% of men2-4, with twin-based heritability estimates of 50-60%5. Mortality rates are higher than those in other psychiatric disorders6, and outcomes are unacceptably poor7. Here we combine data from the Anorexia Nervosa Genetics Initiative (ANGI)8,9 and the Eating Disorders Working Group of the Psychiatric Genomics Consortium (PGC-ED) and conduct a genome-wide association study of 16,992 cases of anorexia nervosa and 55,525 controls, identifying eight significant loci. The genetic architecture of anorexia nervosa mirrors its clinical presentation, showing significant genetic correlations with psychiatric disorders, physical activity, and metabolic (including glycemic), lipid and anthropometric traits, independent of the effects of common variants associated with body-mass index. These results further encourage a reconceptualization of anorexia nervosa as a metabo-psychiatric disorder. Elucidating the metabolic component is a critical direction for future research, and paying attention to both psychiatric and metabolic components may be key to improving outcomes.

All-MXene (2D titanium carbide) solid-state microsupercapacitors for on-chip energy storage

Abstract: On-chip energy storage is a rapidly evolving research topic, opening doors for the integration of batteries and supercapacitors at the microscale on rigid and flexible platforms. Recently, a new class of two-dimensional (2D) transition metal carbides and nitrides (so-called MXenes) has shown great promise in electrochemical energy storage applications. Here, we report the fabrication of all-MXene (Ti3C2Tx) solid-state interdigital microsupercapacitors by employing a solution spray-coating method, followed by a photoresist-free direct laser cutting method. Our prototype devices consisted of two layers of Ti3C2Tx with two different flake sizes. The bottom layer was stacked large-size MXene flakes (lateral dimensions of 3–6 μm) serving mainly as current collectors. The top layer was made of small-size MXene flakes (∼1 μm) with a large number of defects and edges as the electroactive layer responsible for energy storage. Compared to Ti3C2Tx micro-supercapacitors with platinum current collectors, the all-MXene devices exhibited a much lower contact resistance, higher capacitances and better rate-capabilities. Areal and volumetric capacitances of ∼27 mF cm−2 and ∼357 F cm−3, respectively, at a scan rate of 20 mV s−1 were achieved. The devices also demonstrated excellent cyclic stability, with 100% capacitance retention after 10 000 cycles at a scan rate of 50 mV s−1. This study opens up a plethora of possible designs for high-performance on-chip devices employing different chemistries, flake sizes and morphologies of MXenes and their heterostructures.

Layered MgxV2O5·nH2O as Cathode Material for High-Performance Aqueous Zinc Ion Batteries

Abstract: The performance of chemically intercalated V2O5 was found to strongly depend on the interlayer spacing, which is related to the radius of hydrated metal ion, which can be readily tuned by using different intercalated metals. We report a layered Mg2+-intercalated V2O5 as the cathode material for aqueous ZIBs. The large radius of hydrated Mg2+ (∼4.3 A, compared with 3.8 A of commonly used Li+) results in an interlayer spacing as large as 13.4 A (against 11.07 A for Li+-intercalated V2O5), which allows efficient Zn2+ (de)insertion. As a result, the obtained porous Mg0.34V2O5·0.84H2O cathodes work in a wide potential window of 0.1 to 1.8 V versus Zn2+/Zn, and can deliver high capacities of 353 and 264 mA h g–1 at current densities of 100 and 1000 mA g–1, respectively, along with long-term durability. Furthermore, the reversible Zn2+ (de)intercalation reaction mechanism is confirmed by multiple characterizations methods.