Advanced photocatalytic disinfection mechanisms and their challenges.

Currently, microbial contamination issues have globally brought out a huge health threat to human beings and animals. To be specific, microorganisms including bacteria and viruses display durable ecological toxicity and various diseases to aquatic organisms. In the past decade, the photocatalytic microorganism inactivation technique has attracted more and more concern owing to its green, low-cost, and sustainable process. A variety kinds of photocatalysts have been employed for killing microorganisms in the natural environment. However, two predominant shortcomings including low activity of photocatalysts and diverse impacts of water characteristics are still displayed in the current photocatalytic disinfection system. So far, various strategies to improve the inherent activity of photocatalysts. Other than the modification of photocatalysts, the optimization of environments of water bodies has been also conducted to enhance microorganisms inactivation. In this mini-review, we outlined the recent progress in photocatalytic sterilization of microorganisms. Meanwhile, the relevant methods of photocatalyst modification and the influences of water body characteristics on disinfection ability were thoroughly elaborated. More importantly, the relationships between strategies for constructing advanced photocatalytic microorganism inactivation systems and improved performance were correlated. Finally, the perspectives on the prospects and challenges of photocatalytic disinfection were presented. We sincerely hope that this critical mini-review can inspire some new concepts and ideas in designing advanced photocatalytic disinfection systems.

Association between socioeconomic status and hypertension among adults in Fujian province and the mediating effect of BMI and cooking salt intake: a cross-sectional study.

OBJECTIVES: This study aimed to investigate the association between socioeconomic status (SES) and the prevalence of hypertension in Fujian province, China, and to evaluate the mediating effect of body mass index (BMI) and cooking salt intake between SES and hypertension. DESIGN: Community-based cross-sectional survey was conducted between June 2018 and December 2019. SETTING: Fujian province, China. PARTICIPANTS: A total of 26 500 participants aged >18 years completed the survey. OUTCOME MEASURES: The primary outcome was the prevalence of hypertension. Education, income and occupation were used as SES indicators. Meanwhile, certain health behaviours and metabolic risk factors were used as secondary indicators of SES. RESULTS: The prevalence of hypertension was relatively high among participants who finished primary education (34.8%), had the lowest annual income (46.0%), were unemployed or retired (34.7%). Education and income levels were negatively associated with the prevalence of hypertension (p<0.05). Regular smoking, alcohol consumption, BMI and high cooking salt intake were also significantly associated with the prevalence of hypertension (p<0.05). Cooking salt intake was identified as a partial mediator between income and hypertension, mediating 3.45% of the association. Both BMI and cooking salt intake were partial mediators between education and hypertension, mediating 5.23% and 1.93% of the association, respectively. CONCLUSIONS: SES was associated with the prevalence of hypertension among adults in Fujian province, China. BMI and cooking salt intake were partial mediators of the association between SES and hypertension.

Asymmetric Structure Design of Electrolytes with Flexibility and Lithium Dendrite-Suppression Ability for Solid-State Lithium Batteries.

Solid polymer electrolytes can be used to construct solid-state lithium batteries (SSLBs) using lithium metals as the anode. However, the lifespan and safety problems of SSLBs caused by lithium dendrite growth have hindered their practical application. Here, we have designed and prepared a rigid-flexible asymmetric solid electrolyte (ASE) that is used in building SSLBs. The ASE can inhibit efficiently the growth of lithium dendrites and lead to a long cycle life of SSLBs due to the hierarchical structure of a combination of "polymer-in-ceramic" (i.e., rigid ceramic layer of Li6.4La3Zr1.4Ta0.6O12) and "LiBOB-in-polymer" (i.e., soft polymer-layer of polyethylene oxide and LiBOB components). The results demonstrated that a symmetrical battery with ASE (Li|ASE|Li) can be steadily cycled for more than 2000 h and yielded a flat plating/stripping voltage profile under a current density of 0.1 mA cm-2. As a consequence, the SSLB of LiFePO4|ASE|Li delivered a specific capacity of 155.1 mA h g-1 with a capacity retention rate up to 90.2% after 200 cycles with the Coulombic efficiency over 99.6% per cycle. This asymmetric structure combines the advantages of ceramics and polymers, providing an ingenious solution for building rigid and flexible solid electrolytes.

3D web freestanding RuO2-Co3O4 nanowires on Ni foam as highly efficient cathode catalysts for Li-O2 batteries.

The mechanism of Li-O2 batteries is based on the reactions of lithium ions and oxygen, which hold a theoretical higher energy density of approximately 3500 W h kg-1. In order to improve the practical specific capacity and cycling performance of Li-O2 batteries, a catalytically active mechanically robust air cathode is required. In this work, we synthesized a freestanding catalytic cathode with RuO2 decorated 3D web Co3O4 nanowires on nickel foam. When the specific capacity was limited at 500 mA h g-1, the RuO2-Co3O4/NiF had a stable cycling life of up to 122 times. The outstanding performance can be primarily attributed to the robust freestanding Co3O4 nanowires with RuO2 loading. The unique 3D web nanowire structure provides a large surface for Li2O2 growth and RuO2 nanoparticle loading, and the RuO2 nanoparticles help to promote the round trip deposition and decomposition of Li2O2, therefore enhancing the cycling behavior. This result indicates the superiority of RuO2-Co3O4/NiF as a freestanding highly efficient catalytic cathode for Li-O2 batteries.