3D Printed Integrated Gradient-Conductive MXene/CNT/Polyimide Aerogel Frames for Electromagnetic Interference Shielding with Ultra-Low Reflection

Construction of advanced electromagnetic interference(EMI)shielding materials with miniaturized,programmable structure and low reflection are promising but challenging.Herein,an integrated transition-metal carbides/carbon nanotube/polyimide(gradient-conductive MXene/CNT/PI,GCMCP)aerogel frame with hierarchical porous structure and gradient-conductivity has been constructed to achieve EMI shielding with ultra-low reflection.The gradient-conductive structures are obtained by continuous 3D printing of MXene/CNT/poly(amic acid)inks with different CNT contents,where the slightly conductive top layer serves as EM absorption layer and the highly conductive bottom layer as reflection layer.In addition,the hierarchical porous structure could extend the EM dissipation path and dissipate EM by multiple reflections.Consequently,the GCMCP aerogel frames exhibit an excellent average EMI shielding efficiency(68.2 dB)and low reflection(R=0.23).Furthermore,the GCMCP aerogel frames with miniaturized and programmable structures can be used as EMI shielding gaskets and effectively block wireless power transmission,which shows a prosperous application prospect in defense industry and aerospace.

Nanobiochar for the remediation of contaminated soil and water:challenges and opportunities

Although research on biochar has received increasing attention for environmental and agricultural applications,the significance of nanobiochar for environmental pollutant remediation is poorly understood.In contrast to bulk biochar,nanobiochar has superior physicochemical properties such as high catalytic activity,unique nanostructure,large specific surface area and high mobility in the soil environment.These unique characteristics make nanobiochar an ideal candidate for pollution remediation.Thus far,the research on nanobiochar is still in its infancy and most of the previous studies have only been conducted for exploring its properties and environmental functions.The lack of in-depth summary of nanobiochar’s research direction makes it a challenge for scientists and researchers globally.Hence in this review,we established some key fabrication methods for nanobiochar with a focus on its performance for the removal of pollutants from the environment.We also provided up-to-date information on nanobiochar’s role in environmental remediation and insights into different mechanisms involved in the pollutant removal.Although,nanobiochar application is increasing,the associated drawbacks to the soil ecosystem have not received enough research attention.Therefore,further research is warranted to evaluate the potential environmental risks of nanobiochar before large scale application.

Interaction and combined toxicity of microplastics and per-and polyfluoroalkyl substances in aquatic environment

Microplastics(MPs)are recognized as vectors for the transport of organic contaminants in aquatic environments in addition to their own adverse effects on aquatic organisms.Per-and polyfluoroalkyl substances(PFASs)are widely present in aquatic environments due to their widespread applications,and thus coexist with MPs.Therefore,we focus on the interaction of MPs and PFASs and related combined toxicity in aquatic environments in this work The adsorption of PFASs on MPs is critically reviewed,and new mechanisms such as halogen bonding,π-πinteraction,cation-πinteractions,and micelle formation are proposed.Moreover,the effect of MPs on the transport and transformation of PFASs in aquatic environments is discussed.Based on four typical aquatic organisms(shellfish,Daphnia,algae,and fish),the toxicity of MPs and/or PFASs at the organismal or molecular levels is also evaluated and summarized.Finally,challenges and research perspectives are proposed,and the roles of the shapes and aging process of MPs on PFAS biogeochemical processes and toxicity,especially on PFAS substitutes,are recommended for further investigation.This review provides a better understanding of the interactions and toxic effects of coexisting MPs and PFASs in aquatic environments.

Roadmap of environmental health research on emerging contaminants: Inspiration from the studies on engineered nanomaterials

Research on the environmental health of emerging contaminants is critical to understand their risks before causing severe harm.However,the low environmental concentrations,complex behaviors,and toxicology of emerging contaminants present enormous challenges for researchers.Here,we reviewed the research on the environmental health of engineered nanomaterials(ENMs),one of the typical emerging contaminants,to enlighten pathways for future research on emerging contaminants at their initial exploratory stage.To date,some developed pretreatment methods and detection technologies have been established for the determination of ENMs in natural environments.The mechanisms underlying the transfer and transformation of ENMs have been systematically explored in laboratory studies.The mechanisms of ENMs-induced toxicity have also been preliminarily clarified at genetic,cellular,individual,and short food chain levels,providing not only a theoretical basis for revealing the risk change and environmental health effects of ENMs in natural environments but also a methodological guidance for studying environmental health of other emerging contaminants.Nonetheless,due to the interaction of multiple environmental factors and the high diversity of organisms in natural environments,health effects observed in laboratory studies likely differ from those in natural environments.We propose a holistic approach and mesocosmic model ecosystems to systematically carry out environmental health research on emerging contaminants,obtaining data that determine the objectivity and accuracy of risk assessment.

纳米针尖状质子化聚苯胺负载的单原子铂催化剂实现高效酸性电解水制氢

开发高性能单原子铂催化剂对酸性电解水制氢领域具有重要意义.在酸性电解液中,氢离子(H^(+))会被水分子包围并形成水合氢离子,这会导致单原子铂活性位点的局部H^(+)浓度降低,从而使其析氢反应动力学受到限制.本研究通过将单原子铂负载在纳米针尖状质子化聚苯胺上,它既能捕获水合氢离子中的H^(+),又能通过促进电荷积累以加快H^(+)的电化学还原,从而提高单原子铂的析氢反应动力学.结果表明,相比于扁平状质子化聚苯胺负载的单原子铂,针尖状质子化聚苯胺负载的单原子铂的析氢反应转换频率得到显著提高.结合X射线光电子能谱、有限元模拟和电化学行为研究,我们发现局部H^(+)富集促使的氢溢流现象对提升纳米针尖状质子化聚苯胺负载的单原子铂催化剂的析氢活性具有重要贡献.

Nano-black carbon(biochar)released from pyrogenic carbonaceous matter as a super suspending agent in water/soil environments

Nano-black carbon(BC)is one of the most active fractions in the pyrogenic carbonaceous matter continuum.The majority of recent studies mainly focus on the role of nano-BC in the global carbon cycle.However,based on literature and our recent studies,we suggest that nano-BC may also serve as a super suspending agent,carrier,and redox mediator for sorbates during its migration from terrestrial to water bodies due to its unique properties such as high colloidal stability,strong sorption capacity,and high surface reactivity.The full implications of nano-BC in water/soil environments are far more than we expected.Thus,we call for more detailed investigations on the activity and reactivity of nano-BC in water/soil environments.

Correction to:Nano-black carbon(biochar)released from pyrogenic carbonaceous matter as a super suspending agent in water/soil environments

The article“Nano-black carbon(biochar)released from pyrogenic carbonaceous matter as a super suspend-ing agent in water/soil environments”,written by Fei Lian,Zhenyu Wang and Baoshan Xing was originally published electronically on the publisher’s internet portal on 23th of November 2020 without open access.With the author(s)’decision to opt for Open Choice the copyright of the article changed on December 2020 to©“The Author(s)2020”and the article is forthwith distributed under a Creative Com-mons Attribution 4.0 International License(https://creat iveco mmons.org/licen ses/by/4.0/),which permits use,shar-ing,adaptation,distribution and reproduction in any medium or format,as long as you give appropriate credit to the origi-nal author(s)and the source,provide a link to the Creative Commons license,and indicate if changes were made.The original article has been corrected.