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1.
    
Efficient hydrogen release from ammonia borane (AB) with a striking hydrogen content (19.6 wt%) via thermolysis provides a promising pathway for on-board applications utilizing hydrogen energy. However, the sluggish kinetics at low temperatures and high energy consumption of thermal dehydrogenation are major obstacles for hydrogen release from AB. Herein, a novel solar-driven strategy for hydrogen production from AB at low temperature is proposed, in which Ti2O3 is utilized as a full-spectrum light absorber for photothermal-activating solid-state AB reactants to produce hydrogen. Through a reduction transformation method, nanoscale Ti2O3 particles with high chemical stability and narrow band gap are prepared, realizing a rapid production of 2.0 equivalents of hydrogen from AB at ambient temperature, with an excellent recyclable and full-spectrum-responsive photothermal dehydrogenation. Importantly, a record high photothermal activation efficiency of 35% is achieved with nanoscale Ti2O3 particles due to an enhanced local photothermal effect contributed by improved light absorption and decreased thermal conduction. Moreover, assisted with CuCl2 promoter, a release of 2.0 equivalents of hydrogen under 1.0 solar irradiation at 70 °C is successfully achieved, revealing its potential applications in practical vehicles based on proton exchange membrane fuel cells.  相似文献   

2.
    
Passive solar-driven interfacial evaporation is an environmental-friendly approach for seawater desalination. However, non-volatile salts usually precipitate on the evaporator surface during evaporation, significantly reducing the evaporation rate and blocking the evaporator. Although several strategies have been proposed for this issue, they are usually only effective under low salinity conditions and natural solar irradiation. In this study, a scalable solar evaporator is proposed, which is expediently fabricated by carbonizing the commercially available coconut fiber cloth, through designing and optimizing an asymmetric bi-layer structure with a trapezoidal evaporation surface and a wide leg-strengthened water supply pathway. Both experimental and simulation results indicate that the evaporator presents ultra-high salt tolerance, which keeps running steadily for consecutive 14 days under the high salinity of 14 wt% NaCl and high irradiation of 4 suns. This excellent salt resistance arises from a diode-like ion migration introduced by its asymmetric structure. Meanwhile, a remarkable evaporation rate of 7.28 kg m−2 h−1 is also achieved under the harsh condition, resulting from the high solar absorbance and the reduced evaporation enthalpy of the evaporator. Such an evaporator is confirmed as a simple, low-cost, scalable, efficient, and long-term stable device for producing freshwater under harsh desalination conditions.  相似文献   

3.
    
Realizing ultrathin water and generating an abundant water/air interface in the interconnected pores of photothermal materials is an effective way to boost the solar-driven water evaporation rate, but still a great challenge. Herein, confinement capillarity (CC) of photothermal thin coating on porous sponge for significantly enhancing the solar-driven water evaporation is proposed. The thin coating is composed of abundant agminated black/hydrophilic nanoparticles (BHNPs), and the channels among the BHNPs can generate strong capillarity for water transportation. Water can be spontaneously limited and transported among the agminated nanoparticles, rather than fill in the interconnected pores of the sponge. Thus, ultrathin water layer can be realized on the outer/inner surface of the sponge skeleton, without precisely controlling water supply. The thin water layer can not only expose as much evaporation area as possible by increasing the vapor escape channel, but also prevent solar energy to heat excess water. Thanks to the CC, the rate of solar steam generation can be greatly improved. Moreover, the photothermal material with CC can maintain its high evaporation rate during the whole day, and can remove the salt during night time, highlighting its recyclability and anti-salt-accumulation property. Moreover, the CC can be readily scaled up for practical applications.  相似文献   

4.
    
Solar-driven interfacial evaporation (SIE) of brine may solve the fresh water shortage issue but suffers from salt-fouling. Meanwhile, adsorption can extract valuable lithium (Li) from brine but is hampered by low adsorption capacity/rate, additional energy input and low selectivity, etc. Here, as a proof-of-concept, the design of a separated solar evaporator (S-evaporator) is reported for simultaneously efficient fresh water collection and Li+ selective adsorption by SIE of brine, accomplishing their complementation using only sunlight. The S-evaporator consists of a tilted n-shaped H2TiO3-modified fabric and a photothermal sheet on it. The superhydrophilic fabric transports brine to the photothermal sheet and provides affluent sites for Li+ adsorption. The photothermal sheet promotes SIE and enhances Li+ adsorption by significantly increasing the fabric's temperature. Consequently, simultaneous fresh water collection and Li+ selective adsorption are realized by the S-evaporator. Under 1 kW m−2 illumination, the S-evaporator shows long-term stable evaporation rate (1.51 kg m−2 h−1) for 20 wt% brine, high Li+ adsorption capacity (20.09 mg g−1), good Li+ adsorption selectivity from real brine and good cycle stability. The S-evaporator has great application potential for efficiently extracting fresh water and Li+ from brine as demonstrated by the large SIE setup in real outdoor conditions.  相似文献   

5.
    
Interfacial solar steam generation offers a promising and cost-effective way for saline water desalination. However, salt accumulation and deposition on photothermal materials during saline and brine evaporation is detrimental to the stability and sustainability of solar evaporation. Although several antisalt strategies are developed, it is difficult to simultaneously achieve high evaporation rates ( > 2.0 kg m−2 h−1) and energy efficiencies. In this study, a self-rotating photothermal evaporator with dual evaporation zones (i.e., high-temperature and low-temperature evaporation zones) is developed. This photothermal evaporator is sensitive to weight imbalance ( < 15 mg) thus is able to quickly respond to salt accumulation by rotation to refresh the evaporation surface, while the dual evaporation zones optimize the energy nexus during solar evaporation, simultaneously realizing excellent salt-resistant performance and high evaporation rate (2.6 kg m−2 h−1), which can significantly contribute to the real-world application of solar steam generation technology.  相似文献   

6.
Recently, owing to the great structural tunability, excellent photothermal property, and strong photobleaching resistance, organic-small-molecule photothermal materials are proposed as promising solar absorbent materials. Herein, through fusing two strong electron-withdrawing units dibenzo[f,h]quinoxaline and anthraquinone units, a rigid planar acceptor dibenzo[a,c]naphtho[2,3-h]phenazine-8,13-dione (PDN) with stronger electron-withdrawing ability is obtained and used to construct donor–acceptor-type organic-small-molecule solar-energy-absorbing material, 2,17-bis(diphenylamino)dibenzo[a,c]naphtho[2,3-h]phenazine-8,13-dione (DDPA-PDN). The new compound exhibits a strong intramolecular charge transfer character and conjugates rigid plane skeleton, endowing it with a broadband optical absorption from 300 to 850 nm in the solid state, favorable photothermal properties, high photothermal conversion ability, and good photobleaching resistance. Under laser irradiation at 655 nm, the solid photothermal conversion efficiency of the resulting DDPA-PDN molecule reaches 56.23%. Additionally, DDPA-PDN-loaded cellulose papers equipped with abundant microchannels for water flow are integrated with thermoelectric devices, thus achieving an evaporation rate and voltage as high as 1.07 kg m−2 h−1 and 83 mV under 1 kW m−2 solar irradiation, respectively. This study demonstrates the application of photothermal organic-small-molecules in water evaporation and power generation, therefore offering a valuable prospect of their utilization in solar energy harvesting.  相似文献   

7.
    
Solar-driven interfacial evaporation systems are considered as promising technology to alleviate the water scarcity crisis, yet lack of innovative evaporators obstructs further improvement of energy utilization efficiency. Herein, inspired by mangrove, the structure-engineered design is utilized to synthesis multi-level reflection TiN/TiO2@carbon cloth (CC) nanotubes array. The hollowed TiO2 nanorods can promote expeditious water transport, while the TiN/TiO2 array can act as localized surface plasmon resonance (LSPR)-enhanced multi-level reflection structure for solar energy harvesting. The enhanced light absorption capability of the bionic nanostructure is confirmed by finite-difference time-domain (FDTD) simulations. Therefore, the TiN/TiO2@CC-3 exhibits high evaporation rate of 2.02 kg m−2 h−1 under 1 solar illumination, which is comparable or better than most of fabric-based evaporators. When applied in wide acid–base (pH 1–13) and salinity range (8–100 ‰) over 15 days, the TiN/TiO2@CC-3 displays outstanding durability. Furthermore, to expand application scope of the elaborate nanostructure, photothermal-enhanced photocatalysis and thermoelectricity generation applications are evaluated, while these new functionalities are integrated into solar-driven desalination system. The outdoor device exhibits daily water yield of 10.89 kg m−2, synergy with maximum 200.7 mV output voltage and high dye degradation efficiency, demonstrating flexible applications in multi-functional interfacial evaporation systems according to various requirements.  相似文献   

8.
    
Growing concern about photothermal tumor therapy (PTT) as a promising alternative to conventional liver cancer treatment, which is a treatment strategy that utilizes near-infrared (NIR) light-induced photothermal agents (PTAs) to yield photothermal effects to localize thermal damage for tumors. Herein, given the gap between experimental research and clinical application, this review seeks to timely summarize and highlight the recent progress of PTAs used for photothermal treatment of liver cancer in vivo and in vitro in the last five-year. The implications of various PTAs on the multifunctional photothermal conversion capability, the structure-performance correlations of PTT, together with the evaluation of their potential in application are systematically dissected to further dig out what the buried mechanism is. Besides, higher requirements are put forward for the discrepancies and crucial issues faced by different PTAs in PTT with related medical technical obstacles being conquered, which lays a solid theoretical foundation for the medical field of oncology treatment as a whole, especially liver cancer. Finally, it is expected that this review can present valuable guidance for the design of efficient, photostability, and biosafety-aware PTAs for anticancer therapy while stepping into the fast traffic lane for the conversion from bench to bedside in the foreseeable future.  相似文献   

9.
A three-plasmon hybrid, in which core–shell Au@Cu2−xS hybrids are bonded with ultrathin Ti3C2Tx MXene, is prepared for high-efficiency photothermal conversion and membrane-based solar water evaporation for the first time. The MXene/Au nanorod@Cu2−xS hybrids display excellent photothermal conversion efficiency under irradiation of an 808 laser, causing by the three-plasmon-induced synergistic plasmonic absorption and heating effects as well as the multichannel charge transfer between the components. Then, Au nanosphere@Cu2−xS and Au nanorod@Cu2−xS hybrids are mixed and combined with MXene to serve as the membrane material, which shows excellent light absorption ranging from ultraviolet to near-infrared region. By transferring the membrane materials on a hydrophilic cotton piece, the as-prepared photothermal membrane displays a high evaporation rate of 2.023 kg m−2 h−1 and light-to-heat conversion efficiency of 96.1% under 1-sun irradiation due to the synergistic photothermal conversion and over 96% of solar light absorption efficiency. Furthermore, a home-made solar evaporation device enabling automatic inflow of untreated water and outflow of evaporated water is designed based on the principles of liquid pressure and connectors. The seawater desalination and sewage treatment experiments performed on the device and membrane indicate the great potential in solar-light-driven water purification and drinkable water generation.  相似文献   

10.
    
Continuous, thin, oriented zeolite A membranes are produced by a two‐step synthesis on macroporous α‐Al2O3 supports. In the first step, zeolite A nano‐cubes with ～350‐nm edges are prepared as a native impurity phase in zeolite Y synthesis dispersions, the support surface is pre‐modified with a cationic polymer having a selective affinity for zeolite A. The thus‐treated support is contacted with a colloidally stable dispersion of zeolite A and Y mixture in water, which results in selective, dense‐packed deposition of the zeolite A cubes with one face aligned to the average support surface. In a second step of hydrothermal epitaxial growth, the seed layer grows epitaxially into a continuous, meso‐defect free, ～1 µm thick zeolite A layer, already after 1 h of treatment. This microstructure of the membrane compares very favorably to what is commonly obtained. The pH value of the zeolite mixture suspension is found to have a major influence on seed layer morphology, and thereby, on the quality and orientation of zeolite A membrane after short synthesis times. The final zeolite A membrane thickness and morphology is controlled by varying secondary growth synthesis time. The approach presented is thought to be of generic use for the preparation of oriented zeolite membranes.  相似文献   

11.
    
Solar‐enabled evaporation for seawater desalination is an attractive, renewable, and environment‐friendly technique, and tremendous progress has been achieved by developing various photothermal membranes. However, traditional photothermal membranes directly float on water, resulting in some limitations such as unavoidable heat‐loss to bulk water and severe salt accumulation. To solve these problems, a hydrophilic, polymer nanorod‐coated photothermal fabric is designed and fabricated, and then an indirect‐contact evaporation system by hanging the fabric is demonstrated. The two ends of the fabric are designed to be in contact with seawater to guide water flow through capillary suction. Both arc‐shaped top/bottom surfaces of the hanging fabrics are exposed to air, which can prevent heat dissipation to bulk seawater and facilitate the double‐surface evaporation upon sunlight irradiation. Our design leads to an efficient evaporation rate of 1.94 kg m?2 h?1 and high solar efficiency of 89.9% upon irradiation with sunlight (1.0 kW m?2). Importantly, the highly concentrated brine can drip from the bottom of the arc‐shaped fabric, without the appearance of solid‐salt accumulation. This indirect‐contact evaporation system establishes a new path to continuously and economically produce watersteam from seawater for fresh‐water and concentrated brine for the chlor‐alkali industry.  相似文献   

12.
在半导体器件制造,冶金及表面物理研究领域中,越来越多地要涉及超薄超纯的高熔点材料薄膜的制备,本文对我们研制的一种可蒸发难熔材料的微型电子束蒸发枪作一简要的描述。  相似文献   

13.
    
Conversion of solar energy into heat for water evaporation is of great significance to provide clean and sustainable technology for water purification by using inexhaustible sunlight. In this field, one of the challenges comes from the design of high-performance photothermal materials powerful in light harvesting, light-to-heat conversion, and water activation. Herein, it is demonstrated that rationalization of the ionic covalent organic framework (iCOF) can simultaneously satisfy these multiple requirements and a new iCOF STTP is constructed through the Schiff base chemistry in a rapid microwave-assisted solvothermal route by using a hydrophilic dye molecule safranineT as the ionic building block. The integrated dye-related ionic moieties greatly strengthen the light absorbance (>97%) throughout the entire solar spectrum from UV–vis to the infrared region. The framework ionic moieties provide strong polarization to reduce the exciton dissociation energy for enhanced photothermal effect, and in addition, promote sufficient water activation to decrease the water evaporation enthalpy. As an outcome, the STTP driven solar water evaporator affords a fast water evaporation rate of 3.55 kg h−1 m−2 and high solar-to-vapor efficiency of 95.8%. This study highlights the potential of designing iCOF materials for photothermal applications.  相似文献   

14.
    
Nanofiltration membrane plays an increasingly important role in many industrial applications, such as water treatment and resource recovery. The performance of the smart nanofiltration membrane is largely controlled by pore size, the Donnan effect, and surface wettability, which are determined by the function of stimuli-responsive components. Smart membranes, which contain stimuli-responsive components, are capable of changing their physical and chemical properties in response to changes in the environment so that the microstructure of the membrane will have more efficient performances and broader application prospects than the current traditional nanofiltration membranes. Herein, the preparation methods of stimuli-responsive membranes are described and they are systematically classified accordingly to their mechanisms. Moreover, the latest progress of stimuli-responsive membranes in nanofiltration and the main mechanism of each stimuli-response type through relevant examples are discussed and summarized. Finally, this review provides new insights into the remaining challenges and future directions of stimuli-responsive membranes. Fueled by advances in chemistry and materials science, it is expected to build a smart and efficient nanofiltration membrane platform for the benefit of mankind.  相似文献   

15.
    
Solar-enabled thermal management is emerging as a promising candidate to exploit green, low-cost and efficient heat-related applications, which has drawn extensive intensity for the development of solar-to-thermal materials with high-performance and desirable functionality. However, there still remain considerable challenges, such as the sharp temperature fluctuations under water-related environment, high cost, complex fabrication approaches and limited energy efficiency. Here, superhydrophobic and photothermal nanostructured Janus membranes composed of hierarchical candle soot and transparent polydimethylsiloxane is proposed in a simple, low-cost, and effective way. The achieved membranes can readily adapt to curved surfaces and enable efficient solar-to-thermal capability of ≈68 °C under 1 sun and good water-repellant property of ≈159.7. Therefore, it can still maintain stable temperature without remarkable temperature decline when exposed to the high-moisture environment. Also, the asymmetric structure can further endow the membrane with declined heat dissipation for high-performance thermal management. Moreover, it can further function as a self-supported agricultural film to continuously heat the soils with stable temperature for efficient bean growth, demonstrating significant potential in the new generation of urban agriculture.  相似文献   

16.
Asymmetric membranes are prepared via the non‐solvent‐induced phase separation (NIPS) process from a polystyrene‐block‐poly(N,N‐dimethylaminoethyl methacrylate) (PS‐b‐PDMAEMA) block copolymer. The polymer is prepared via sequential living anionic polymerization. Membrane surface and volume structures are characterized by scanning electron microscopy. Due to their asymmetric character, resulting in a thin separation layer with pores below 100 nm on top and a macroporous volume structure, the membranes are self‐supporting. Furthermore, they exhibit a defect‐free surface over several 100 µm2. Polystyrene serves as the membrane matrix, whereas the pH‐ and temperature‐sensitive minority block, PDMAEMA, renders the material double stimuli‐responsive. Therefore, in terms of water flux, the membranes are able to react on two independently applicable stimuli, pH and temperature. Compared to the conditions where the lowest water flux is obtained, low temperature and pH, activation of both triggers results in a seven‐fold permeability increase. The pore size distribution and the separation properties of the obtained membranes were tested through the pH‐dependent filtration of silica particles with sizes of 12–100 nm.  相似文献   

17.
    
Photothermal conversion, heat localization and water supply are the keys to achieving efficient solar-driven interfacial evaporation. However, effective coupling between the three aspects at the air/liquid interface remains challenging. Herein, Au@Ag-Pd trimetallic nanostructure/polystyrene (PS) microsphere Janus structures are designed as the solar absorber and thermal insulator. The Janus structures deposited on a water supply layer act as a 2D interfacial solar evaporator. The PS microsphere localizes heat at micrometer scale and enhances plasmonic absorption of the Au@Ag-Pd nanocrystals supported on the microsphere. Meanwhile, the Janus structures divide the surface of water supply layer into multiple regions with sub-micrometer depths, lowering the evaporation enthalpy. Owing to the synergic effects of these components, the evaporator realizes a solar-to-vapor conversion efficiency of 99.1% and an evaporation rate of 3.04 kg m−2 h−1 in pure water under 1 sun illumination. The efficient solar-driven evaporation can last for over 40 h. Furthermore, the solar evaporator shows high-performance seawater desalination with salt removal ratios of near 100%. This study brings new insights for controlling evaporation thermodynamics and kinetics. The Janus nano-micro structure design can be extended to other systems for various solar-thermal applications.  相似文献   

18.
    
Recently, atmospheric water harvesting (AWH) based on hygroscopic salt on an inorganic or organic carrier has attracted great attention because of its significant potential applications in the environment. The major technical challenges for practical applications are how to prevent the leakage of hygroscopic salt while achieving a high capacity for sorption of atmospheric water and a high sorption rate. Additionally, techniques for converting sorbed water (in the form of a lithium chloride (LiCl) solution) into clean water need to be developed. Here, a novel method for continuous atmospheric water harvesting, leveraging LiCl@PHEA hydrogels is introduced. Synthesized via one-step UV polymerization in saturated LiCl solutions, these hydrogels exhibit remarkable air distension ability (>60 times), achieving high water sorption efficiency (11.18 gg−1 at 90% relative humidity in 30 min) with over 90 wt.% salt content and no leakage. This water collection system integrates a porous evaporator and a 3D-printed silica substrate, ensuring an extraordinarily high evaporation rate (>11 kgm−2 h−1 under sunlight) and efficient water transmission. A prototype based on this achieves a record-breaking collection rate of over 5 kgm−2 h−1, enabling large-scale efficient atmospheric water harvesting. Additionally, continuous hydrogen production through electrolysis using the collected water (< 5 ppm of salts) is demonstrated.  相似文献   

19.
    
The integration of actively‐functional receptors into nanoscale networks outperformed competent detection devices and other ion‐sensing designs. Synthesis of azo chromophores with long hydrophobic tails showed an ecofriendly sensing and an extreme selectivity for divalent mercury analytes. In order to tailor the tip to HgII ion‐sensing functionality, we manipulated the chromophores into nanoscale membrane discs, which led to small, easy‐to‐use optical sensor strips. The design of these hydrophobic probes into ordered pore‐based membranes transformed the ion‐sensing systems into smart, stable assemblies and portable laboratory assays. The nanosensor membrane strips with chemical and mechanical stability allowed for reversible, stable and reusable detectors without any structural damage, even under rigorous chemical treatment for several numbers of repeated cycles. The optical membrane strips provided HgII ion‐sensing recognition for both cost‐ and energy‐saving systems. Indeed, the synthetic strips proved to have an efficient ability for various analytical applications, targeting especially for on‐site and in situ chemical analyses, and for continuous monitoring of toxic HgII ions. On the proximity‐sensing front, these miniaturized nanomembrane strips can revolutionize the consumer and industrial market with the introduction of the probe surface‐mount naked‐eye ion‐sensor strips.  相似文献   

20.
    
Myeloid‐derived suppressor cells (MDSCs) are garnering increasing attention given their role in tumor development. Herein, a nano‐enabled strategy is demonstrated for the eradication of tumor‐infiltrated MDSCs by reversing hypoxia. Oxygen‐independent photodynamic bismuth tungstate nanoparticles (Bi2WO6 NPs) are loaded into reactive oxygen species (ROS) responsive platelet membranes (PMs) to form a hybrid (PM‐BiW NPs). P‐Selectin on PMs endows PM‐BiW NPs with selectivity toward cancer cells. Once in the tumor, laser illumination stimulates the Bi2WO6 NPs photothermally and photodynamically, which produces enormous quantities of hydroxyl radicals. These hydroxyl radicals help rupture the PM and mitigate hypoxia with the assistance of ionizing radiation. This effectively remodels the tumor microenvironment toward one disfavoring the recruitment of MDSCs and contributes to better prognosis. To better understand the mechanism, the expression levels of a set of markers are monitored. It is found that the downregulations of hypoxia‐inducible factor‐1α, ectonucleoside triphosphate diphosphohydrolase 2, and adenosine‐5‐phosphoricacid are behind the blocked infiltration of MDSCs. This platform strategy offers a promising approach to overcome the immunosuppression caused by MDSCs through a trimodal therapy integrating the power of photothermal and photodynamic therapy in addition to radiation therapy.  相似文献   

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