Boosting extraction of Pb in contaminated soil via interfacial solar evaporation of multifunctional sponge

Interfacial solar water evaporation is a reliable way to accelerate water evaporation and contaminant remediation.Embracing the recent advance in photothermal technology,a functional sponge was prepared by coating a sodium alginate(SA)impregnated sponge with a surface layer of reduced graphene oxide(rGO)to act as a photothermal conversion medium and then subsequently evaluated for its ability to enhance Pb extraction from contaminated soil driven by interfacial solar evaporation.The SA loaded sponge had a Pb adsorption capacity of 107.4 mg g^(-1).Coating the top surface of the SA sponge with rGO increased water evaporation performance to 1.81 kg m^(-2)h^(-1)in soil media under one sun illumination and with a wind velocity of 2 m s^(-1).Over 12 continuous days of indoor evaporation testing,the Pb extraction efficiency was increased by 22.0%under 1 sun illumination relative to that observed without illumination.Subsequently,Pb extraction was further improved by 48.9%under outdoor evaporation conditions compared to indoor conditions.Overall,this initial work shows the significant potential of interfacial solar evaporation technologies for Pb contaminated soil remediation,which should also be applicable to a variety of other environmental contaminants.

Harvesting,sensing and regulating light based on photo-thermal effect of Cu@CuO mesh

A system of light harvesting, sensing and regulating was designed based on the photo-thermal and Seebeck effect of flexible CuO nanostructures. Cu@CuO meshes were prepared via self-oxidation of Cu mesh and utilized as the photo-thermal material. Upon irradiation by visible light, the temperature of the Cu@CuO mesh dramatically increases. The temperature difference between the irradiated and non-irradiated parts of the Cu@CuO mesh produced a measurable voltage output due to the Seebeck effect. The generated voltage was then converted into a digital signal to control a rotary neutral-density disc to filter the received light. This enabled regulation of the intensity of the incident light at a selected region. This system is cost effective and has potential applications in greenhouses, factories and smart buildings to minimize energy consumption and improve wellbeing.

Ag nanoparticles anchored organic/inorganic Z‐scheme 3DOMM‐TiO_(2‒x)‐based heterojunction for efficient photocatalytic and photoelectrochemical water splitting

Narrow spectral response,low charge separation efficiency and slow water oxidation kinetics of TiO_(2)limit its application in photoelectrochemical and photocatalytic water splitting.Herein,a promising organic/inorganic composite catalyst Ag/PANI/3DOMM‐TiO_(2–x)with a three‐dimensional ordered macro‐and meso‐porous(3DO MM)structure,oxygen vacancy and Ti^(3+)defects,heterojunction formation and noble metal Ag was designed based on the Z‐scheme mechanism and successfully prepared.The Ag/PANI/3DOMM‐TiO_(2–x)ternary catalyst exhibited enhanced hydrogen production activity in both photocatalytic and photoelectrochemical water splitting.The photocatalytic hydrogen production rate is 420.90μmol g^(–1)h^(–1),which are 19.80 times and 2.06 times higher than the commercial P25 and 3DOMM‐TiO_(2),respectively.In the photoelectrochemical tests,the Ag/PANI/3DOMM‐TiO_(2–x)photoelectrode shows enhanced separation and transfer of carriers with a high current density of 1.55 mA cm^(–2)at equilibrium potential of 1.23 V under simulated AM 1.5 G illumination,which is approximately 5 times greater than the 3DOMM‐TiO_(2).The present work has demonstrated the promising potential of organic/inorganic Z‐scheme photocatalyst in driving water splitting for hydrogen production.

Recent innovations in 3D solar evaporators and their functionalities

Interfacial solar evaporation(ISE)has emerged as a promising technology to alleviate global water scarcity via energy-efficient purification of both wastewater and seawater.While ISE was originally identified and developed during studies of simple double-layered two-dimensional(2D)evaporators,observed limitations in evaporation rate and functionality soon led to the development of three-dimensional(3D)evaporators,which is now recognized as one of the most pivotal milestones in the research field.3D evaporators significantly enhance the evaporation rates beyond the theoretical limits of 2D evaporators.Furthermore,3D evaporators could have multifaceted functionalities originating from various functional evaporation surfaces and 3D structures.This review summarizes recent advances in 3D evaporators,focusing on rational design,fabrication and energy nexus of 3D evaporators,and the derivative functions for improving solar evaporation performance and exploring novel applications.Future research prospects are also proposed based on the in-depth understanding of the fundamental aspects of 3D evaporators and the requirements for practical applications.

Bio-inspired inorganic-protein coating on Mg-based biomaterials for bioengineering applications

Developing smart and advanced functional materials inspired by the unparalleled complexity and efficiency of biological tissues has received much attention across various fields.Magnesium alloys,particularly pure magnesium,have emerged as notable candidates in orthopedics and dentistry due to their exceptional biocompatibility,degradability,and ability to promote bone regeneration[1].However,the highly reactive chemical nature of magnesium and its rapid degradation upon exposure to water.

Recent strategies for constructing efficient interfacial solar evaporation systems

Interfacial solar evaporation(ISE)is a promising technology to relieve worldwide freshwater shortages owing to its high energy conversion efficiency and environmentally sustainable potential.So far,many innovative materials and evaporators have been proposed and applied in ISE to enable highly controllable and efficient solar-to-thermal energy conversion.With rational design,solar evaporators can achieve excellent energy management for lowering energy loss,harvesting extra energy,and efficiently utilizing energy in the system to improve freshwater production.Beyond that,a strategy of reducing water vaporization enthalpy by introducing molecular engineering for water-state regulation has also been demonstrated as an effective approach to boost ISE.Based on these,this article discusses the energy nexus in two-dimensional(2D)and three-dimensional(3D)evaporators separately and reviews the strategies for design and fabrication of highly efficient ISE systems.The summarized work offers significant perspectives for guiding the future design of ISE systems with efficient energy management,which pave pathways for practical applications.

Porous carbon-based thermally conductive materials:Fabrication,functions and applications

The demand for electronic devices has dramatically increased in the past few years.Efficient electronic devices require excellent thermal management systems to extend their operation time and prevent heat accumulation from affecting performance.Carbonaceous materials are considered as one of the ideal thermal management materials due to their excellent physiochemical stability.In addition,since porous-structured carbon materials typically exhibit outstanding thermal conductivity,low density,and large contact area,they have attracted considerable attention from both academia and industry in the last decades.In this review,methods and strategies for the preparation of highly thermally conductive porous carbon-based materials and the factors that influence their thermal conductivity of the materials are summarized.The thermal performance of porous carbonaceous materials fabricated by different approaches and their applications are also discussed.Finally,the potential challenges and strategies for the development and applications of highly thermally conductive porous carbona-ceous materials are discussed.

A photothermal reservoir for highly efficient solar steam generation without bulk water

A solid photothermal reservoir is designed to implement solar-steam generation in the absence of bulk water.The photothermal reservoir is composed of a water absorbing core encapsulated by a photothermal reduced graphene oxide based aerogel sheet which absorbs light and converts it into heat thus evaporating the stored water.The photothermal reservoir is able to store 6.5 times its own weight in water,which is sufficient for one day solar evaporation,thus no external water supplement is required.During solar-steam generation,since no bulk water is involved,the photothermal reservoir minimizes heat conduction loss,and maximizes both of the exposed evaporation surface area and net energy gain from the environment,leading to an energy efficiency beyond the theoretical limit.An extremely high water evaporation rate of 4.0 kg m-2 h-1(normalized to projection area)is achieved in laboratory studies over a cylinder photothermal reservoir with a diameter of 5.2 cm and a height of 15 cm under 1.0 sun irradiation.Practical evaluation of the photothermal reservoir outdoors as part of a desalination device demonstrates a similar evaporation rate where the salinity of the clean water produced is lower than 24 ppb.Thus the photothermal reservoir shows great potential for real world applications in portable solarthermal desalination.

Boosting solar steam generation by structure enhanced energy management

Interfacial solar-steam generation is a promising and cost-effective technology for both desalination and wastewater treatment.This process uses a photothermal evaporator to absorb sunlight and convert it into heat for water evaporation.However solar-steam generation can be somewhat inefficient due to energy losses via conduction,convection and radiation.Thus,efficient energy management is crucial for optimizing the performance of solar-steam generation.Here,via elaborate design of the configuration of photothermal materials,as well as warm and cold evaporation surfaces,performance in solar evaporation was significantly enhanced.This was achieved via a simultaneous reduction in energy loss with a net increase in energy gain from the environment,and recycling of the latent heat released from vapor condensation,diffusive reflectance,thermal radiation and convection from the evaporation surface.Overall,by using the new strategy,an evaporation rate of 2.94 kg m^-2 h^-1,with a corresponding energy efficiency of solar-steam generation beyond theoretical limit was achieved.

Enhancing solar steam generation using a highly thermally conductive evaporator support

Interfacial solar steam generation is an efficient water evaporation technology which has promising applications in desalination,sterilization,water purification and treatment.A common component of evaporator design is a thermal-insulation support placed between the photothermal evaporation surface and bulk water.This configuration,common in 2-dimensional(2 D)evaporation systems,minimizes heat loss from evaporation surface to bulk water,thus localizing the heat on the evaporation surface for efficient evaporation.This design is subsequently directly adopted for 3-dimensional(3 D)evaporators without any consideration if it is appropriate.However,unlike 2 D solar evaporators,the 3 D evaporators can also harvest additional energy(other than solar light)from the air and bulk water to enhance evaporation rate.In this scenario,the use of thermal insulator support is not proper since it will hinder energy extraction from water.Here,the traditional 3 D evaporator configuration was completely redesigned by using a highly thermally conductive material,instead of a thermal insulator,to connect evaporation surfaces and the bulk water.Much higher evaporation rates were achieved by this strategy,owing to the rapid heat transfer from the bulk water to the evaporation surfaces.Indoor and outdoor tests both confirmed that evaporation performance could be significantly improved by substituting a thermal insulator with thermally conductive support.These findings will redirect the future design of 3 D photothermal evaporators.

More from less:improving solar steam generation by selectively removing a portion of evaporation surface

Using minimal photothermal material to achieve maximum evaporation rate is extremely important for practical applications of interfacial solar evaporation technology.In this work,we found that with the increase in the size of evaporation surfaces,the evaporation rate decreased.Both experimental and numerical simulation results confirmed that when the evaporation surface size increased,the middle portion of the evaporation surface acted as a‘‘dead evaporation zone”with little contribution to water evaporation.Based on this,the middle portion of the evaporation surface was selectively removed,and counterintuitively,both the evaporation rate and vapor output were increased due to the reconfigured and enhanced convection above the entire evaporation surface.As such,this work developed an important strategy to achieve a higher evaporation rate and increased vapour output while using less material.

Mechanically Strong and Highly Stiff Supramolecular Polymer Composites Repairable at Ambient Conditions

It is a formidable challenge to fabricate healable polymeric materials with high mechanical strength and stiffness due to the highly suppressed diffusion of their polymer chains.Herein,a high-strength,highly stiff,andrepairable/healable supramolecular polymercomposite was fabricatedby complexingpoly(acrylic acid)(PAA)and poly(allylamine hydrochloride)(PAH)in aqueous solutions,followed by molding into desired shapes.Exquisitely tuning the electrostatic and H-bonding interactions between PAA and PAH led to associative phase-separation and in situ formation of nanostructures in the resultant PAA–PAH composites.