Diagnosing and Correcting the Failure of the Solid-State Polymer Electrolyte for Enhancing Solid-State Lithium-Sulfur Batteries.

Solid-state polymer electrolytes (SPEs) attract great interest in developing high-performance yet reliable solid-state batteries. However, understanding of the failure mechanism of the SPE and SPE-based solid-state batteries remains in its infancy, posing a great barrier to practical solid-state batteries. Herein, the high accumulation and clogging of "dead" lithium polysulfides (LiPS) on the interface between the cathode and SPE with intrinsic diffusion limitation is identified as a critical failure cause of SPE-based solid-state Li-S batteries. It induces a poorly reversible chemical environment with retarded kinetics on the cathode-SPE interface and in bulk SPEs, starving the Li-S redox in solid-state cells. This observation is different from the case in liquid electrolytes with free solvent and charge carriers, where LiPS dissolve but remain alive for electrochemical/chemical redox without interfacial clogging. Electrocatalysis demonstrates the feasibility of tailoring the chemical environment in diffusion-restricted reaction media for reducing Li-S redox failure in the SPE. It enables Ah-level solid-state Li-S pouch cells with a high specific energy of 343 Wh kg-1 on the cell level. This work may shed new light on the understanding of the failure mechanism of SPE for bottom-up improvement of solid-state Li-S batteries.

Sustainable Carbon Materials toward Emerging Applications.

It is desirable for a sustainable society that the production and utilization of renewable materials are net-zero in terms of carbon emissions. Carbon materials with emerging applications in CO2 utilization, renewable energy storage and conversion, and biomedicine have attracted much attention both academically and industrially. However, the preparation process of some new carbon materials suffers from energy consumption and environmental pollution issues. Therefore, the development of low-cost, scalable, industrially and economically attractive, sustainable carbon material preparation methods are required. In this regard, the use of biomass and its derivatives as a precursor of carbon materials is a major feature of sustainability. Recent advances in the synthetic strategy of sustainable carbon materials and their emerging applications are summarized in this short review. Emphasis is made on the discussion of the original intentions and various sustainable strategies for producing sustainable carbon materials. This review provides basic insights and significant guidelines for the further design of sustainable carbon materials and their emerging applications in catalysis and the biomedical field.

Synthesis of Colloidal Mesoporous Silica Spheres with Large Through-Holes on the Shell.

Colloidal silica spheres with controllable large through-holes and mesopores on the shell were synthesized by using polystyrene (PS) spheres as a hard template and cationic surfactant hexadecyl trimethylammonium bromide (CTAB) as a soft template. Through modulating the synthetic conditions, including the volume ratio of ethanol (EtOH)/water, the amount of ammonia hydroxide, and the dosage of CTAB, SiO2 spheres can transform among hollow structure, through-hole structure, and no large pore structure. The investigation suggests that the hydrolysis rate of the silica source and the interaction strength between the PS sphere template and SiO2 may determine the large pore structure of the final product. The moderate hydrolysis rate of tetraethyl orthosilicate (TEOS) and strong interaction between the PS sphere template and SiO2 is conductive to the formation of large through-holes in SiO2 spheres. To further investigate the pore structure of through-holes of SiO2 spheres, the lysozyme (Lz) was selected as a model molecule for adsorption experiments. The Lz adsorption experiments show that SiO2 spheres with through-hole structure exhibit a much faster adsorption rate than SiO2 spheres with hollow structure and higher adsorption capacity than SiO2 with no large pore structure. Such a behavior could find interesting applications in the fields that require a fast-loading characteristic.

Synthesis and applications of porous non-silica metal oxide submicrospheres.

Nowadays the development of submicroscale products of specific size and morphology that feature a high surface area to volume ratio, well-developed and accessible porosity for adsorbates and reactants, and are non-toxic, biocompatible, thermally stable and suitable as synergetic supports for precious metal catalysts is of great importance for many advanced applications. Complex porous non-silica metal oxide submicrospheres constitute an important class of materials that fulfill all these qualities and in addition, they are relatively easy to synthesize. This review presents a comprehensive appraisal of the methods used for the synthesis of a wide range of porous non-silica metal oxide particles of spherical morphology such as porous solid spheres, core-shell and yolk-shell particles as well as single-shell and multi-shell particles. In particular, hydrothermal and low temperature solution precipitation methods, which both include various structure developing strategies such as hard templating, soft templating, hydrolysis, or those taking advantage of Ostwald ripening and the Kirkendall effect, are reviewed. In addition, a critical assessment of the effects of different experimental parameters such as reaction time, reaction temperature, calcination, pH and the type of reactants and solvents on the structure of the final products is presented. Finally, the practical usefulness of complex porous non-silica metal oxide submicrospheres in sensing, catalysis, biomedical, environmental and energy-related applications is presented.

A review of greywater characteristics and treatment processes.

This paper presents a comprehensive literature review of different characteristics of greywater (GW) and current treatment methods. GW is domestic wastewater excluding toilet waste and can be classified as either low-load GW (excluding kitchen and laundry GW) or high-load GW (including kitchen and/or laundry). This review provides information on the quantity of GW produced, its constituents (macro and micro), existing guidelines for wastewater reuse, current treatment methods (from storage to disinfection) as well as related costs and environmental impacts. Moreover some successful examples from various countries around the world are examined. The current preferred treatments for GW use physical and biological/natural systems. Recently, chemical systems like coagulation, adsorption and advanced oxidation processes (AOPs) have been considered and have been successful for low to moderate strength GW. The presence of xenobiotic organic compounds (XOC), which are hazardous micropollutants in GW, is emphasised. Since conventional treatments are not efficient at removing XOC, it is recommended that future studies look at chemical treatment, especially AOPs that have been found to be successful at mineralising recalcitrant organic compounds in wastewater.