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Abstract A precursor for Li 3 PS 4 solid electrolyte was successfully prepared by reaction of Li 2 S and P 2 S 5 in ethyl acetate. The precursor was composed of Li 3 PS 4 and ethyl acetate in a molar ratio of 1:2, as determined by thermogravimetry-differential thermal analysis (TG-DTA). Upon drying at 160 °C, the precursor decomposed to form crystalline Li 3 PS 4 with a high ionic conductivity of 3.3 × 10 − 4 S cm − 1 and low activation energy of about 31 kJ mol − 1 .

In view of the burgeoning demand for energy storage stemming largely from the growing renewable energy sector, the prospects of high (>300 °C), intermediate (100-200 °C) and room temperature (25-60 °C) battery systems are encouraging. Metal sulfur batteries are an attractive choice since the sulfur cathode is abundant and offers an extremely high theoretical capacity of 1672 mA h g −1 upon complete discharge. Sodium also has high natural abundance and a respectable electrochemical reduction potential (−2.71 V vs. standard hydrogen electrode). Combining these two abundant elements as raw materials in an energy storage context leads to the sodium-sulfur battery (NaS). This review focuses solely on the progress, prospects and challenges of the high and intermediate temperature NaS secondary batteries (HT and IT NaS) as a whole. The already established HT NaS can be further improved in terms of energy density and safety record. The IT NaS takes advantage of the lower operating temperature to lower manufacturing and potentially operating costs whilst creating a safer environment. A thorough technical discussion on the building blocks of these two battery systems is discussed here, including electrolyte, separators, cell configuration, electrochemical reactions that take place under the different operating conditions and ways to monitor and comprehend the physicochemical and electrochemical processes under these temperatures. Furthermore, a brief summary of the work conducted on the room temperature (RT) NaS system is given seeking to couple the knowledge in this field with the one at elevated temperatures. Finally, future perspectives are discussed along with ways to effectively handle the technical challenges presented for this electrochemical energy storage system.

Investigation of the excited state decay dynamics of transition metal systems is a crucial step for the development of photoswitchable molecular based ma- terials with applications in growing fields as energy conversion, data storage or molecular devices. The photophysics of these systems is an entangled problem arising from the interplay of electronic and geometrical rearrangements that take place on a short time scale. Several factors play a role in the process: various electronic states of di↵erent spin and chemical character are involved, the system undergoes important structural variations and several nonradiative processes can occur. Computational chemistry is a useful tool to get insight into the micro- scopic description of the photophysics of these materials since it provides unique information about the character of the electronic spin states involved, the ener- getics and time evolution of the system. In this review article, we present an overview of the state of the art methodologies available to address the several aspects that have to be incorporated to properly describe the deactivation of excited states in transition metal complexes. The most recent developments in theoretical methods are discussed and illustrated with examples.

Conventional petroleum-derived plastics represent a serious problem for global pollution because, when discarded in the environment, are believed to remain for hundreds of years. In order to reduce dependence on fossil resources, bioplastic materials are being proposed as safer alternatives. Bioplastics are bio-based and/or biodegradable materials, typically derived from renewable sources. Food waste as feedstock represents one of the recent applications in the research field of bioplastics production. To date, several food wastes have been used as raw materials for the production of bioplastics, including mostly fruit and vegetable wastes. The conversion of fruit and vegetable wastes into biomaterials could occur through simple or more complex processes. In some cases, biopolymers extracted from raw biomass are directly manufactured; on the other hand, the extracted biopolymers could be reinforced or used as reinforcing agents and/or natural fillers in order to obtain biocomposites. The present review covers available results on the application of methods used in the last 10 years for the design of biomaterials obtained from formulations made up with both fruits and vegetables by-products. Particular attention will be addressed to the waste pre-treatment, to the bioplastic formulation and to its processing, as well as to the mechanical and physical properties of the obtained materials.

The development of sustainable energy solutions that reduce global carbon emissions, while maintaining high living standards, is one of the grand challenges of the current century. Transportation fuels are critical to economic development, globalization, and the advancement of society. Although ground vehicles and small aircraft are beginning a slow transition toward electric propulsion with energy sourced from solar radiation or wind, the extreme power requirements of jet aircraft require a more concentrated source of energy that is conveniently provided by liquid hydrocarbon fuels. This Review describes recent efforts to develop efficient routes for the conversion of crude biomass sources (e. g., lignocellulose) to cycloalkanes. These cycloalkanes impart advantageous properties to jet fuels, including increased density, higher volumetric heat of combustion, and enhanced operability. The combination of bio-based cycloalkanes and synthetic paraffinic kerosenes allows for the preparation of 100 % bio-based fuels that can outperform conventional petroleum-based fuels. In this Review methods are described that convert biomass-derived small molecules, including furfural, furfuryl alcohol, 5-hydroxymethylfurfural, cyclic ketones, phenolics, acyclic ketones, cyclic alcohols, furans, esters, and alkenes to high-density cycloalkanes. In addition to describing the chemical transformations and catalysts that have been developed to efficiently produce various cycloalkanes, this Review includes summaries of key fuel properties, which highlight the ability to generate fuels with customized performance metrics. This work is intended to inspire other researchers to study the conversion of sustainable feedstocks to full-performance aviation fuels. An acceleration of this research is critical to reducing the carbon footprint of commercial and military aviation on a timescale that will help blunt the impacts of global warming.

High-voltage spinel LiNi0.5Mn1.5O4 cathode materials typically exhibit a perfect octahedral morphology; i.e., only the {111} planes are observed. However, a truncated octahedral morphology is sometimes observed with the appearance of both the {100} planes and the {111} planes. The underlying mechanism of this morphological transformation is unclear. CS corrected scanning transmission electron microscopy (STEM) techniques were used to study LiNi0.5Mn1.5O4 samples lifted by a focused ion beam (FIB) to determine the atomic-level crystal and electronic structures of the octahedral and truncated octahedral morphologies. STEM images directly show that the appearance of the {100} planes in the truncated octahedral particles of LiNi0.5Mn1.5O4 is closely associated with the atomic-level migration of Ni and Mn ions in the surface region. The STEM electron energy loss spectroscopy (EELS) confirms the presence of oxygen-deficient and Ni-rich areas, particularly in the region close to the newly formed {100} planes. Th...

Control over the competition between an organometallic hexamer macrocycle and oligomer chains formed from the non-alternant aromatic 1,3-dibromoazulene (DBAz) precursor has been achieved in surface-assisted synthesis on a copper(111) surface. In contrast to kinetic reaction control via the high-dilution principle, the ring formation is achieved here by thermodynamic control, which is based on two-dimensional (2D) confinement and reversible bonds.

High performance and stable catalysts for two-step thermochemical water splitting are key to synthesising direct fuels in the form of H2 or liquid hydrocarbon fuels by the Fischer–Tropsch process. Herein, we designed and synthesised LaMnO3 perovskite structured oxides doped on both the A and B sites for two-step thermochemical water splitting. First, Ca2+, Sr2+ and Ba2+ divalent cations were successfully doped on the A site of LaMnO3 and the thermochemical water splitting performances were analysed. After that, Al3+ and Ga3+ ions were doped on the B site of the perovskites produced in the first step. Through this strategy, a novel perovskite composition (La0.6Ca0.4Mn0.8Ga0.2O3) was found with remarkable water splitting performance, producing 401 μmol g−1 of H2 at low thermochemical cycle temperatures between 1300 and 900 °C. The as-prepared perovskite exhibits twelve times higher H2 production than the benchmark CeO2 catalyst under the same experimental conditions. This novel perovskite is also capable of maintaining steady-state redox activity during the water splitting cycles.

Voltage decay in a charging–discharging cycle restricts the commercial application of Li-rich layered oxides as a cathode material for next-generation lithium-ion batteries with high energy density...

S.K.K. and H.S. contributed equally to this work. The financial support from the Australian government through the Australian Research Council (ARC) and Australian Renewable Energy Agency (ARENA) is gratefully acknowledged. Access to the facilities of the Australian National Fabrication Facility (ANFF) is also gratefully acknowledged.