Search

Water evaporation and steam production have been recognized to be considerably crucial due to the vast applications, ranging from waste water treatment, water purification, to alternative green energy solutions by water splitting, catalysis, and in-door heating. Albeit the big variety of photothermal conversion materials (PCMs) developed for this purpose, certain drawbacks, e.g. high cost, complicated synthesis, weak/narrow absorbance, bulkiness, and low evaporation rate, have hindered the application potential. Herein, we report the dual-phase molybdenum nitride nanorambutans, synthesized by a facile method, for solar steam generation. Not only the inherent properties, including strong full-spectrum absorbance, high-efficiency photothermal conversion, and super-hydrophilicity, benefit their water evaporation performance, the interconnected open mesopores of the nanorambutans further boost their capability of light harvesting and water/vapor transportation. Solar energy conversion efficiency of ∼97% under one sun together with excellent cycling stability has been demonstrated. In the desalination systems, integrating with the high salt rejection rate, the nanorambutans film can produce a water evaporation rate as high as ∼1.70 kg m −2 h −1 with an efficiency of ∼98%. Besides its compact size, the record-breaking water evaporation performance of these nanorambutans has exceeded the previous best inorganic PCM. This work introduces molybdenum nitride as a new PCM for efficient solar steam generation and all applications that can benefit from highly localized heating from nano to macro scale.

Solar steam generation (SSG) is a promising approach to address the global shortage of freshwater by seawater treatment, but commonly suffers from salt-accumulation related issues, drastically reducing the operational efficiency and lifetime of SSG systems. Herein, we propose a strategy for sustainable SSG from seawater, enabling powerful self-salt-discharge and self-water-pumping by constructing a closed loop between water and salt. As a result, besides an evaporation rate as high as 2.8 kg m-2 h-1 (under one sun), neither salt accumulation nor evaporation rate decline is observed upon long-term cycling of over one month or constant floating on seawater over eight months. Even upon continuous desalination in a highly concentrated solution (20 wt% NaCl) for over 400 h or under high-intensity irradiation for over 12 h, the high evaporation rate is successfully maintained. This work thus provides an effective solution for salt accumulation, addressing the top challenge for long-term sustainable desalination. This journal is

Pathogenic microbes cause infections and are excellent at adapting to the disinfection strategies that address their biochemistry. The growth in number of drug resistant superbugs is alarming, and has attracted attention to alternative solutions. In recent years, researchers have put effort into designing nanomaterials with activatable antimicrobial properties initiated by light irradiation. The underlying mechanisms of these nanomaterials' photoactivatable antimicrobial effect may vary from reactive oxygen species generation, to heat production or pH variation in procedures like photocatalysis, photodynamic therapy, photothermal lysis and photoinduced acidification. In this article, we review the photoactive nanomaterial solutions for fighting against microbial diseases, especially bacterial infections. This Review shines light on the fundamental principles, important developments, promising applications, and limitations of current technologies as well as open questions that these methods may answer or help to answer.

LiNbO3 (LN) crystal has been widely used as a pyroelectric material due to its spontaneous electric polarization, which could be recharged easily and can directly convert heat energy into electricity. LN crystal’s heat-resistant, low-cost, and low dielectric loss properties make it possible for its applications in room-temperature pyroelectric devices and thermal sensors. However, LN crystal suffers from fragility, inflexibility, and other mechanical properties, which limit its suitability for many applications in various fields. In this study, the LN modified flexible pyroelectric films, composed of LN micro-particles, polypropylene (PP) matrix, and multiwalled carbon nanotubes (MWCNTs), are successfully fabricated. The pyroelectric effects of LN crystal and LN/PP/MWCNT composite films are characterized by monitoring the patterned self-assembly of nanoparticles and the output pyroelectric currents. The excellent pyroelectric properties of the composites have potential applications in energy harvesters or sensors.

Transition metal selenides (TMSs) with excellent electrochemical activity and high intrinsic electrical conductivity have attracted considerable attention owing to their potential use in energy storage devices. However, the low energy densities of the reported TMSs, which originate from the small active surface area and poor electrolyte ion mobility, substantially restrict their application potential. In this work, porous ultrathin nickel selenide nanosheet networks (NiSe NNs) on nickel foam are fabricated by using a novel, facile method, that is, selenylation/pickling of the pre-formed manganese-doped α-Ni(OH) 2. Removal of Mn resulted in NNs with a highly porous structure. The 3D framework of the NNs and the inherent nature of the NiSe affords high ion mobility, abundant accessible activated sites, vigorous electrochemical activity, and low resistance. One of the highest specific capacities of TMSs ever reported, that is, 443 mA h g −1 (807 μAh cm −2) at 3.0 A g −1, is achieved with the NNs as electrodes. The assembled NiSe NNs//porous carbon hybrid supercapacitor delivers a high energy density of 66.6 Wh kg −1 at a power density of 425 W kg −1, with excellent cycling stability. This work provides a new strategy for the production of novel electrode materials that can be applied in high-performance hybrid supercapacitors, and a fresh pathway towards commercial applications of hybrid supercapacitors based on TMS electrodes.

Waterborne health issues continue to grow despite the large number of available solutions. Current sterilization techniques to fight with waterborne diseases struggle to meet the demands on cost, efficiency and reach. Effective alternatives are pressingly required. Here we introduce Prussian blue coated ferroferric oxide (Fe 3 O 4 @PB) composites for water sterilization. The composites exhibit superior photothermal inactivation of bacteria under solar-light irradiation, with nearly complete inactivation of bacterial cells in only 15 min. Even for the mixed bacteria in authentic water matrices, the composites show excellent bacterial inactivation performance. Moreover, the highly magnetized iron core of the Fe 3 O 4 @PB enables magnetic separation and recycling. Multiple cycle runs reveal that Fe 3 O 4 @PB composites have exceptional stability and reusability. This work demonstrates a scalable, low-cost, high-efficiency and reusable sterilization method to improve water quality and safety.

The development of polymer-based nanoparticles to ferry siRNA continues to evolve. It is becoming increasingly apparent that gene silencing nanoparticles produced by conventional bulk manufacturing techniques often exhibit physicochemical heterogeneity within and between batches that can affect the biological performance. Here a new facile and robust “chip-free” method is presented, termed chip-free agitation-generated droplets (CAD) preparation, using chitosan-based gene silencing nanoparticles as an example. The CAD-prepared silencing particles, in comparison to the particles prepared by the conventional bulk protocol, exhibit lower surface charge (9 mV vs 21 mV at N/P = 5), higher stability (≈40% higher binding affinity and up to 30% less morphological deformation), and are less prone to aggregation measured by nanoparticle tracking analysis over a period of one month. Furthermore, these physical attributes contribute up to 19% higher in cell viability at N/P = 5, while the gene silencing of enhanced green fluorescent protein remains constant in a human cell line. Control of particle properties is necessary to advance siRNA-based delivery; the CAD preparation represents a physical complement to chemical design modifications, which can be readily transferred among research labs and utilized for alternative polymer systems.

Submitted by Manuel Brandão (recipp@sc.ipp.pt) on 2017-07-03T11:18:52Z No. of bitstreams: 1 ART_GoretiSales_BioMark_2016.pdf: 3869975 bytes, checksum: 5da7617e49133905896c5d48aa51ee60 (MD5) Approved for entry into archive by Ana Rebelo (amsr@isep.ipp.pt) on 2017-07-13T11:13:32Z (GMT) No. of bitstreams: 1 ART_GoretiSales_BioMark_2016.pdf: 3869975 bytes, checksum: 5da7617e49133905896c5d48aa51ee60 (MD5) Made available in DSpace on 2017-07-13T11:13:32Z (GMT). No. of bitstreams: 1 ART_GoretiSales_BioMark_2016.pdf: 3869975 bytes, checksum: 5da7617e49133905896c5d48aa51ee60 (MD5) Previous issue date: 2016 info:eu-repo/semantics/publishedVersion