Highlights
The 3D honeycomb-like fabric decorated with MXene is woven as solar evaporator.
The honeycomb structure enables light-trapping and recycling of convective and radiative heat.
The 3D ...honeycomb-fabric evaporator possesses high solar efficiency up to 93.5% under 1 sun irradiation and excellent salt harvesting ability.
Solar steam generation technology has emerged as a promising approach for seawater desalination, wastewater purification, etc. However, simultaneously achieving superior light absorption, thermal management, and salt harvesting in an evaporator remains challenging. Here, inspired by nature, a 3D honeycomb-like fabric decorated with hydrophilic Ti
3
C
2
T
x
(MXene) is innovatively designed and successfully woven as solar evaporator. The honeycomb structure with periodically concave arrays creates the maximum level of light-trapping by multiple scattering and omnidirectional light absorption, synergistically cooperating with light absorbance of MXene. The minimum thermal loss is available by constructing the localized photothermal generation, contributed by a thermal-insulating barrier connected with 1D water path, and the concave structure of efficiently recycling convective and radiative heat loss. The evaporator demonstrates high solar efficiency of up to 93.5% and evaporation rate of 1.62 kg m
−2
h
−1
under one sun irradiation. Moreover, assisted by a 1D water path in the center, the salt solution transporting in the evaporator generates a radial concentration gradient from the center to the edge so that the salt is crystallized at the edge even in 21% brine, enabling the complete separation of water/solute and efficient salt harvesting. This research provides a large-scale manufacturing route of high-performance solar steam generator.
The synthesis and preparation of a new type of graphene composite material suitable for spin‐coating into conductive, transparent, and flexible thin film electrodes in ambient conditions is reported ...here for the first time. Solution‐processible graphene with diameter up to 50 μm is synthesized by surfactant‐assisted exfoliation of graphite oxide and in situ chemical reduction in a large quantity. Spin‐coating the mixing solution of surfactant‐functionalized graphene and PEDOT:PSS yields the graphene composite electrode (GCE) without the need for high temperature annealing, chemical vapor deposition, or any additional transfer‐printing process. The conductivity and transparency of GCE are at the same level as those of an indium tin oxide (ITO) electrode. Importantly, it exhibits high stability (both mechanical and electrical) in bending tests of at least 1000 cycles. The performance of organic light‐emitting diodes based on a GCE anode is comparable, if not superior, to that of OLEDs made with an ITO anode.
A transparent, flexible, low‐temperature, and solution‐processible graphene composite electrode (GCE) is fabricated based on large‐size, highly soluble, chemically derived graphene. The performance of organic light‐emitting diodes (OLEDs) based on a GCE anode is comparable, if not superior, to that of OLEDs made with an ITO anode.
In this study, high-purity V2CTx MXene was successfully synthesized by etching V2AlC with fluoride and hydrochloric acid mixed solution using a hydrothermal-assisted method. This method is more ...concise and effective and has a low level of danger. The morphology and structure of the V2CTx MXene was characterized by X-ray diffraction, field emission scanning electron microscopy, and X-ray photoelectron spectroscopy. The electrochemical properties were investigated as an anode material for lithium ion batteries. The results show that the prepared V2CTx had a higher purity and showed excellent electrochemical properties as an anode of lithium-ion batteries. And V2CTx prepared with different etching system can he obtained with high yield and excellent purity by changing the reactive conditions of the system. However, electrochemical performance of V2CTx MXene obtained at different etching system is quite different. V2CTx synthesized in the mixed solution of ammonium fluoride and hydrochloric acid has the best performance, which originates from more accessible active sites for ion in the enlarged interlayer distance, and the smaller impedance of V2CTx.
Graphene has been highlighted in a variety of wearable electronics and smart textiles applications due to its unique properties such as high conductivity, transparency, flexibility and other ...excellent mechanical performance. Although there have been extensive efforts for graphene based conductive fibers/yarns, there are remaining challenges in terms of the seamless integration between 2D flakes, and reduced charge transport in a lower carrier concentration. Unstable resistance probably arises from the creation of gaps in the conductive parts of the smart textile. Also, regional temperatures can get too high, constituting a fire-safety hazard and endangering the wearer's safety. In this work, the synergistic effect of graphene and flame-retardant materials was investigated, and a conductive fabric was developed which is highly conductive and flame retardancy. Graphene has excellent electrical and thermal conductivity and acts synergistically with traditional flame-retardants on common fabrics. The electrical surface resistivity of hybrid material modified fabrics was as low as 0.54 kΩ/sq, so they could serve as safe and highly conductive conductor in a simple circuit and show excellent wash-ability. The limiting oxygen index of the fabric increased from 19 to 32 after modification in conjunction with the residue at 800 °C increased from 17.9 to 31%, which could be used as safe and highly conductive materials for smart textiles and wearable devices.
In this study, the gelling ability and lubrication performance of N-octadecyl-D-gluconamides (NOG) in liquid paraffin (LP), pentaerythritol oleate (PE-OA), and polyethylene glycol (PEG) oils were ...systemically investigated. The NOG, which could gelate the investigated oils, was successfully synthesized by a one-step method. The prepared gel lubricants were completely thermoreversible and exhibited improved thermal stability, according to the thermogravimetry analysis (TGA) reports. Rheological tests confirmed that the NOG gelator could effectively regulate the rheological behavior of the base oils. Tribological evaluation suggested that NOG, as an additive in the three types of base oils, could remarkably reduce the friction and wear in steel contacts. A plausible mechanism for the improved performances was proposed based on the mechanical strength of the gels and the formation of the boundary-lubricating film on the worn surface. The results indicated that NOG is a potential gelator for preparing gel lubricants with excellent tribological properties and environment-friendly characteristics.
Abstract
In this study, the iron-carbon-aluminum (Fe-C-Al) composite filler was prepared by aluminum modification of conventional iron-carbon (Fe-C) micro-electrolysis with a no-burn method. The ...optimal process conditions for Fe-C-Al three-phase micro-electrolysis treatment of low concentration phosphorus wastewater were determined to be the aluminum metal ratio of 14 wt% and solids dosing of 30 g/L. Under the optimal process conditions, Fe-C-Al three-phase micro-electrolysis was performed for the treatment of low concentration phosphorus wastewater (LCPW) with continuous experiment, while iron-carbon fillers before and after treatment were analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that the amount of Fe2+ dissolved in the micro-electrolysis determined the micro-electrolysis phosphorus removal effect, Al promoted the dissolution of Fe2+, and the Fe-C-Al filler had a stable phosphorus removal effect, and the average removal efficiency of phosphorus was 67.40%, which is an average improvement of 29.25% compared with the conventional Fe-C filler. The treatment of LCPW by Fe-C-Al three-phase micro-electrolysis is consistent with a first-order kinetic reaction with apparent activation energy of 38.70 kJ·mol−1, which is controlled by the chemical reaction.
The two-dimensional transition metal carbides or nitrides Ti
3
C
2
T
x
(MXene), has emerged as attractive electrode materials for lithium-ion batteries due to their metallic electrical conductivity ...and low ion diffusion barrier. However, the stabilities, electronic structures and other physicochemical properties of MXene are affected intensively by their surface species and structure. Here, a new architecture approach is demonstrated for reforming MXene through in situ-decorated LaF
3,
for boosting the performance of Li batteries in terms of capacity and rate ability. Ti
3
C
2
T
x
@LaF
3
can deliver an initial specific discharge capacity of 340 mAh/g under a current density of 50 mA/g and a reversible discharge capacity of 89.2 mAh/g at a current density of 1000 mA/g, which is significantly higher than that of pure Ti
3
C
2
T
x
. Ti
3
C
2
T
x
@LaF
3
heterostructures enhance Li‐ion storage performance by shortens the charge transfer distance and improves the charge transfer rate during electrochemical reaction.
Summary
In mammals, DNA methylation is associated with aging. However, age‐related DNA methylation changes during phase transitions largely remain unstudied in plants. Moso bamboo (Phyllostachys ...edulis) requires a very long time to transition from the vegetative to the floral phase. To comprehensively investigate the association of DNA methylation with aging, we present here single‐base‐resolution DNA methylation profiles using both high‐throughput bisulfite sequencing and single‐molecule nanopore‐based DNA sequencing, covering the long period of vegetative growth and transition to flowering in moso bamboo. We discovered that CHH methylation gradually accumulates from vegetative to reproductive growth in a time‐dependent fashion. Differentially methylated regions, correlating with chronological aging, occurred preferentially at both transcription start sites and transcription termination sites. Genes with CG methylation changes showed an enrichment of Gene Ontology (GO) categories in ‘vegetative to reproductive phase transition of meristem’. Combining methylation data with mRNA sequencing revealed that DNA methylation in promoters, introns and exons may have different roles in regulating gene expression. Finally, circular RNA (circRNA) sequencing revealed that the flanking introns of circRNAs are hypermethylated and enriched in long terminal repeat (LTR) retrotransposons. Together, the observations in this study provide insights into the dynamic DNA methylation and circRNA landscapes, correlating with chronological age, which paves the way to study further the impact of epigenetic factors on flowering in moso bamboo.
Significance Statement
Moso bamboo requires a very long time to transition from the vegetative to the floral phase. Here, we found that the DNA methylation level varies with chronological age in moso bamboo. This study also provides insights into flanking introns of circRNAs, which are hypermethylated and enriched in LTR retrotransposons.
The bandgap opening of graphene is extremely important for the expansion of the applications of graphene‐based materials into optoelectronics and photonics. Current methods to open the bandgap of ...graphene have intrinsic drawbacks including small bandgap openings, the use hazardous/harsh chemical oxidations, and the requirement of expensive chemical‐vapor deposition technologies. Herein, an eco‐friendly, highly effective, low‐cost, and highly scalable synthetic approach is reported for synthesizing wide‐bandgap fluorinated graphene (F‐graphene or or fluorographene) semiconductors under ambient conditions. In this synthesis, ionic liquids are used as the only chemical to exfoliate commercially available fluorinated graphite into single and few‐layer F‐graphene. Experimental and theoretical results show that the bandgap of F‐graphene is largely dependent on the F coverage and configuration, and thereby can be tuned over a very wide range.
Fluorinated graphenes: An eco‐friendly, highly effective, low‐cost, and highly scalable approach has been developed to synthesize wide‐bandgap fluorinated graphene (F‐graphene; see figure) semiconductors. Experimental and theoretical results show the F‐graphene bandgaps are largely dependent on the F coverage and configurations, and can be tuned over a very wide range.
A novel, facile, and versatile approach for preparing highly durable, electrically conductive cotton yarns is reported. Polyelectrolyte brushes, a polymer that covalently tethers one end on a ...surface, are first grown from cotton surfaces by surface-initiated atomic transfer radical polymerization. Subsequent electroless deposition of metal particles onto the brush-modified cotton yarns yields electrically conductive yarns, which have conductivity as high as ∼1 S/cm and can be used as electrical wires in wearable, flexible electronic devices. Importantly, the formation of polymer brush-bridged metal/cotton hierarchical structures provides robust mechanical and electrical durability to the yarns under many stretching, bending, rubbing, and washing cycles. With proper selection of metal, the conductivity of the samples remains stable after they are stored in air for a few months. This chemical approach can be extended as a general method for making conductive yarns and fabrics from all kinds of natural fibers.
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