Chemical Scissors Tailored Nano‑Tellurium with High‑Entropy Morphology for Efficient Foam‑Hydrogel‑Based Solar Photothermal Evaporators

The development of tellurium(Te)-based semiconductor nanomaterials for efficient light-to-heat conversion may offer an effective means of harvesting sunlight to address global energy concerns.However,the nanosized Te(nano-Te)materials reported to date suffer from a series of drawbacks,including limited light absorption and a lack of surface structures.Herein,we report the preparation of nano-Te by electrochemical exfoliation using an electrolyzable room-temperature ionic liquid.Anions,cations,and their corresponding electrolytic products acting as chemical scissors can precisely intercalate and functionalize bulk Te.The resulting nano-Te has high morphological entropy,rich surface functional groups,and broad light absorption.We also constructed foam hydrogels based on poly(vinyl alcohol)/nano-Te,which achieved an evaporation rate and energy efficiency of 4.11 kg m^(−2)h^(−1)and 128%,respectively,under 1 sun irradiation.Furthermore,the evaporation rate was maintained in the range 2.5-3.0 kg m^(−2)h^(−1)outdoors under 0.5-1.0 sun,providing highly efficient evaporation under low light conditions.

Ionization Engineering of Hydrogels Enables Highly Efficient Salt‑Impeded Solar Evaporation and Night‑Time Electricity Harvesting

Interfacial solar evaporation holds immense potential for brine desalination with low carbon footprints and high energy utilization.Hydrogels,as a tunable material platform from the molecular level to the macroscopic scale,have been considered the most promising candidate for solar evaporation.However,the simultaneous achievement of high evaporation efficiency and satisfactory tolerance to salt ions in brine remains a challenging scientific bottleneck,restricting the widespread application.Herein,we report ionization engineering,which endows polymer chains of hydrogels with electronegativity for impeding salt ions and activating water molecules,fundamentally overcoming the hydrogel salt-impeded challenge and dramatically expediting water evaporating in brine.The sodium dodecyl benzene sulfonate-modified carbon black is chosen as the solar absorbers.The hydrogel reaches a ground-breaking evaporation rate of 2.9 kg m−2 h−1 in 20 wt%brine with 95.6%efficiency under one sun irradiation,surpassing most of the reported literature.More notably,such a hydrogel-based evaporator enables extracting clean water from oversaturated salt solutions and maintains durability under different high-strength deformation or a 15-day continuous operation.Meantime,on the basis of the cation selectivity induced by the electronegativity,we first propose an all-day system that evaporates during the day and generates salinity-gradient electricity using waste-evaporated brine at night,anticipating pioneer a new opportunity for all-day resource-generating systems in fields of freshwater and electricity.

Nitrogen-doped microporous graphite-enhanced copper plasmonic effect for solar evaporation

Water scarcity is a global challenge,and solar evaporation technology offers a promising and eco-friendly solution for freshwater production.Photothermal conversion materials(PCMs)are crucial for solar evaporation.Improving photothermal conversion efficiency and reducing water evaporation enthalpy are the two key strategies for the designing of PCMs.The desired PCMs that combine both of these properties remain a challenging task,even with the latest advancements in the field.Herein,we developed copper nanoparticles(NPs)with different conjugated nitrogen-doped microporous carbon coatings(Cu@C–N)as PCMs.The microporous carbon enveloping layer provides a highly efficient pathway for water transport and a nanoconfined environment that protects Cu NPs and facilitates the evaporation of water clusters,reducing the enthalpy of water evaporation.Meanwhile,the conjugated nitrogen nodes form strong metal-organic coordination bonds with the surface of copper NPs,acting as an energy bridge to achieve rapid energy transfer and provide high solar-to-vapor conversion efficiency.The Cu@C–N exhibited up to 89.4%solar-to-vapor conversion efficiency and an evaporation rate of 1.94 kgm^(−2) h^(−1) under one sun irradiation,outperforming conventional PCMs,including carbon-based materials and semiconductor materials.These findings offer an efficient design scheme for high-performance PCMs essential for solar evaporators to address global water scarcity.

A Biomass-Based Hydrogel Evaporator Modified Through Dynamic Regulation of Water Molecules:Highly Efficient and Cost-Effective

Solar-driven hydrogel evaporator used for water purification demonstrates great potential in seawater desalination and domestic sewage treatment.However,much uncertainty still exists about the most efficient design to obtain cost-effective drinkable water.In this paper,a natural rich biomass Nicandra physalodes(Linn.)Gaertn.polysaccharide was introduced into the polyvinyl alcohol network to control the water distribution during evaporation and build a low-cost hybrid hydrogel solar evaporator with a total material cost of$7.95 m^(−2).The mixed evaporator works stably in a long-span acid–base range(pH 1–14)and salinity range(0–320 g kg^(−1)).Its daily water purification capacity can reach 24.4 kg m^(−2)with a water purification capacity of 3.51 kg m^(−2)h^(−1)under sunlight.This paper provides a new possibility for a highly efficient and cost-effective water desalination system with guaranteed water quality by focusing on the dynamic regulation of water molecules at the evaporation interface.

Micro–Nano Water Film Enabled High‑Performance Interfacial Solar Evaporation

Interfacial solar evaporation holds great promise to address the freshwater shortage.However,most interfacial solar evaporators are always filled with water throughout the evaporation process,thus bringing unavoidable heat loss.Herein,we propose a novel interfacial evaporation structure based on the micro–nano water film,which demonstrates significantly improved evaporation performance,as experimentally verified by polypyrrole-and polydopamine-coated polydimethylsiloxane sponge.The 2D evaporator based on the as-prepared sponge realizes an enhanced evaporation rate of 2.18 kg m^(−2)h^(−1)under 1 sun by fine-tuning the interfacial micro–nano water film.Then,a homemade device with an enhanced condensation function is engineered for outdoor clean water production.Throughout a continuous test for 40 days,this device demonstrates a high water production rate(WPR)of 15.9–19.4 kg kW^(−1)h^(−1)m^(−2).Based on the outdoor outcomes,we further establish a multi-objective model to assess the global WPR.It is predicted that a 1 m^(2)device can produce at most 7.8 kg of clean water per day,which could meet the daily drinking water needs of 3 people.Finally,this technology could greatly alleviate the current water and energy crisis through further large-scale applications.

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.

A hierarchical salt-rejection strategy for sustainable and high-efficiency solar-driven desalination

Solar steam generation(SSG)is widely regarded as one of the most sustainable technologies for seawater desalination.However,salt fouling severely compromises the evaporation performance and lifetime of evaporators,limiting their practical applications.Herein,we propose a hierarchical salt-rejection(HSR)strategy to prevent salt precipitation during long-term evaporation while maintaining a rapid evaporation rate,even in high-salinity brine.The salt diffusion process is segmented into three steps—insulation,branching diffusion,and arterial transport—that significantly enhance the salt-resistance properties of the evaporator.Moreover,the HSR strategy overcomes the tradeoff between salt resistance and evaporation rate.Consequently,a high evaporation rate of 2.84 kg m^(-2) h^(-1),stable evaporation for 7 days cyclic tests in 20 wt%NaCl solution,and continuous operation for 170 h in natural seawater under 1 sun illumination were achieved.Compared with control evaporators,the HSR evaporator exhibited a>54%enhancement in total water evaporation mass during 24 h continuous evaporation in 20 wt%salt water.Furthermore,a water collection device equipped with the HSR evaporator realized a high water purification rate(1.1 kg m^(-2) h^(-1)),highlighting its potential for agricultural applications.

Experimental Study and Thermal Modelling of Cocoa Shell Convective Drying in an Indirect Solar Dryer

The concern of the present work is the convective drying of empty cocoa shells in an indirect solar dryer. Some drying experiments, using one sample, were carried out. During the experiments, the sample is introduced in the drying chamber. Then at steady time intervals, the sample is withdrawn from the drying chamber, for a rapid weighing. After each weighing, the sample is reintroduced in the dryer. At each time interval, the ambient temperature of the drying chamber and its relative humidity γ are measured by a thermo-hygrometer. From the experimental data, a theoretical determination of the moisture evaporated from the product was performed and a good agreement was found between the theoretical and experimental values, confirmed by the value of the RMSE. Those calculations used the constants in the Nusselt number found in literature. Then those constants were evaluated again, to get new values more suitable with the experimental data. The dimensionless numbers of Nusselt, Grashof and Prandtl were calculated. That allowed the calculation of the average value of the Nusselt number. The average convective heat transfer coefficient was determined.

The Characteristics of the Evaporator/Evaporator for Direct Expansion Solar Assisted Heat Pump System

Direct expansion solar assisted heat pump (DX-SAHP) technology is developed by combining solar energy heat utilization with heat pump energy saving technology. The experimental researches of the DX-SAHP hot water system are conducted in this paper, and overall performance of DX-SAHP is analyzed with three different structures of collectors/evaporators, namely a bare-plate collector, a glass-plate collector and double collectors/evaporators (a bare-plate collector and a glass-plate collector). The influence factors and overall performance are studied, which show that the overall performance of the system is mainly influenced by solar irradiation intensity and the collector area. Comparing with glass-plate collector in similar conditions, bare-plate collector system COP is higher. While increasing collector area is conducive to improve the system COP, but will reduce the collector efficiency and increase the workload of the compressor by comparing the bare-plate collector with double-plate collectors.

Recyclable Fe_(3)O_(4)@Polydopamine(PDA) nanofluids for highly efficient solar evaporation

Volumetric solar evaporations by using light-absorbing nanoparticles suspended in liquids(nanofluids)as solar absorbers have been widely regarded as one of the promising solutions for clean water production because of its high efficiency and low capital cost compared to traditional solar distillation systems.Nevertheless,previous solar evaporation systems usually required highly concentrated solar irradiation and high capital cost,limiting the practical application on a large scale.Herein,for the first time in this work,polydopamine(PDA)-capped nano Fe_(3)O_(4)(Fe_(3)O_(4)@PDA)nanofluids were used as solar absorbers in a volumetric system for solar evaporation.The introduction of organic PDA to nano Fe_(3)O_(4)highly contributed to the high light-absorbing capacity of over 85%in wide ranges of 200–2400 nm because of the existence of numerous carbon bonds and pi(π)bonds in PDA.As a result,high evaporation efficiency of 69.93%under low irradiation of 1.0 kW m^(-2)was achieved.Compared to other nanofluids,Fe_(3)O_(4)@PDA nanofluids also provided an advantage in high unit evaporation rates.Moreover,Fe_(3)O_(4)@PDA nanofluids showed excellent reusability and recyclability owing to the preassembled nano Fe_(3)O_(4),which significantly reduced the material consumptions.These results demonstrated that the Fe_(3)O_(4)@PDA nanofluids held great promising application in highly efficient solar evaporation.

Electron beam evaporation deposition of cadmium sulphide and cadmium telluride thin films: Solar cell applications

Cadmium sulphide （CdS） and cadmium telluride （CdTe） thin films are deposited by electron beam evaporation. Atomic force microscopy （AFM） reveals that the root mean square （RMS） roughness values of the CdS films increase as substrate temperature increases. The optical band gap values of CdS films increase slightly with the increase in the substrate temperature, in a range of 2.42-2.48 eV. The result of Hall effect measurement suggests that the carrier concentration decreases as the substrate temperature increases, making the resistivity of the CdS films increase. CdTe films annealed at 300 ℃ show that their lowest transmittances are due to their largest packing densities. The electrical characteristics of CdS/CdTe thin film solar cells are investigated in dark conditions and under illumination. Typical rectifying and photovoltaic properties are obtained.

The Effect of Annealing under Non-vacuum on the Optical Properties of TiAlN Non-vacuum Solar Selective Absorbing Coating Prepared by Cathodic Arc Evaporation

TiAIN solar selective absorbing coatings which were deposited on 304L stainless steel using cathodic arc evaporation method were annealed under non-vacuum at different temperatures with different times. The optical properties （absorptance and emittance） of the coatings were measured by a spectrophotometer. It was found that, after being annealed for 2 hours at different temperatures, the absorptance of the coatings reached the highest value of 0.92 at 700 ℃ while the emittance got the lowest value of 0.38 at 800 ℃. When the coatings were annealed at 600 ℃ for 24 hours, the optical properties changed to 0.92/0.44 （absorptance/ emittance）. By measuring the structure, morphology, elements and surface roughness of the coatings, it was found that both the elemental composition and the surface roughness of the coatings changed as a result of annealing, and these changes caused the change of the optical properties of the coatings.

Designing high-efficiency light-to-thermal conversion materials for solar desalination and photothermal catalysis

Light-to-thermal conversion materials(LTCMs)have been of great interest to researchers due to their impressive energy conversion capacity and wide range of applications in biomedical,desalination,and synergistic catalysis.Given the limited advances in existing materials(metals,semiconductors,π-conjugates),researchers generally adopt the method of constructing complex systems and hybrid structures to optimize performance and achieve multifunctional integration.However,the development of LTCMs is still in its infancy as the physical mechanism of light-to-thermal conversion is unclear.In this review,we proposed design strategies for efficient LTCMs by analyzing the physical process of light-tothermal conversion.First,we analyze the nature of light absorption and heat generation to reveal the physical processes of light-to-thermal conversion.Then,we explain the light-to-thermal conversion mechanisms of metallic,semiconducting andπ-conjugated LCTMs,and propose new material design strategies and performance improvement methods.Finally,we summarize the challenges and prospects of LTCMs in emerging applications such as solar water evaporation and photothermal catalysis.

In-situ growth of a CdS window layer by vacuum thermal evaporation for CIGS thin film solar cell applications

Highly crystalline and transparent CdS films are grown by utilizing the vacuum thermal evaporation （VTE） method. The structural, surface morphological, and optical properties of the films are studied and compared with those prepared by chemical bath deposition （CBD）. It is found that the films deposited at a high substrate temperature （200 ℃） have a preferential orientation along （002） which is consistent with CBD-grown films. Absorption spectra reveal that the films are highly transparent and the optical band gap values are found to be in a range of 2.44 eV-2.56 eV. Culnl_xGaxSe2 （CIGS） solar cells with in-situ VTE-grown CdS films exhibit higher values of Voc together with smaller values of Jsc than those from CBD. Eventually the conversion efficiency and fill factor become slightly better than those from the CBD method. Our work suggests that the in-situ thermal evaporation method can be a competitive alternative to the CBD method, particularly in the physical- and vacuum-based CIGS technology.

Experimental investigation and cost assessment of the salt production by solar assisted evaporation of saturated brine

The technical feasibility and economy of solar heat collection-forced evaporation process are the keys to its practicality,especially its application in strong brine treatment.The operation cost of applying solar collection in salt manufacturing through depth evaporation of brine has been studied.For Na^+,K^+,Mg^(2+)//Cl^-,SO_4^(2-)-H_2O salt–water system,most of the Na Cl and all of the Carnallite were separated.The operation cost reached the optimum when the heat collection and evaporation were controlled at 75 and 55°C,respectively.When the solar radiation amount was 19557 kJ·m^(-2)·d^(-1),the solar collector area for producing Carnallite was about 34.27 m^2·(t salt)^(-1),and the operation cost was 13 USD?(t salt)^(-1).The energy consumption of salt manufacturing is at least 25%higher than that of natural evaporation.Regarding the economy,the solar assisted salt manufacturing process is recommended to be performed at a production scale of more than 20 tons per day.

Fully Superhydrophilic, Self-Floatable, and Multi-Contamination-Resistant Solar Steam Generator Inspired by Seaweed

Highly hydrophilic materials enable rapid water delivery and salt redissolution in solar-driven seawater desalination. However, the lack of independent floatability inhibits heat localization at the air/water interface. In nature, seaweeds with internal gas microvesicles can float near the sea surface to ensure photosynthesis. Here, we have developed a seaweed-inspired, independently floatable, but superhydrophilic (SIFS) solar evaporator. It needs no extra floatation support and can simultaneously achieve continuous water pumping and heat concentration. The evaporator resists salt accumulation, oil pollution, microbial corrosion, and protein adsorption. Densely packed hollow glass microbeads promote intrinsic floatability and heat insulation. Superhydrophilic zwitterionic sulfobetaine hydrogel provides a continuous water supply, redissolves the deposited salt, and endows the SIFS evaporator with excellent anti-fouling properties. With its unprecedented anti-contamination ability, this SIFS evaporator is expected to open a new avenue for designing floatable superhydrophilic materials and solving real-world issues of solar steam generation in complex environmental conditions.

仿生太阳能驱动界面蒸发器的进展与挑战

太阳能驱动界面蒸发(SDIE)作为一种高效、可持续的水资源获取方法,近年来受到了广泛的关注。基于仿生原理设计的太阳能驱动界面蒸发器在提高能源转换效率、降低盐结晶和抗污染等方面展现了巨大的潜力,在解决淡水资源紧缺和能源短缺等问题上发挥重要作用。该文梳理了近年来的仿生学在SDIE领域的应用,对比了仿生太阳能驱动界面蒸发器的结构、性能和仿生机理,探讨了不同类型仿生太阳能驱动界面蒸发器的优缺点,分析了仿生太阳能驱动界面蒸发器所面临的共性问题,并提出了未来的研究挑战。

太阳能界面蒸发可持续离网脱盐技术研究

随着全球环境污染问题愈发严重,淡水资源日趋匮乏,脱盐淡化技术成为研究热点。传统的脱盐淡化能耗高,太阳能界面蒸发技术能够直接利用可再生能源,清洁环保,是一种环境友好型离网脱盐工艺,可实现降低海水淡化成本和零碳排放的目标。介绍了离网脱盐技术的研究意义及前景,太阳能界面蒸发技术的基本内涵,并详细介绍了各类高效光热转换材料,主要包括光热碳材料、金属及氧化物、高分子聚合物及相关复合材料;归纳总结了太阳能驱动的各类界面蒸发脱盐工艺,主要包括太阳能界面多级闪蒸和多效蒸馏技术、膜蒸馏技术、温室海水淡化技术、太阳能加湿除湿技术及多能耦合脱盐技术等;最后针对当前全球环境和能源问题对未来利用太阳能界面蒸发技术进行离网脱盐未来的研究方向进行了展望。

高效海水淡化的太阳能界面蒸发器研究进展

综述基于光热转换原理的界面蒸发器(SDIE)的最新进展,从性能评估指标和材料设计思路的角度出发,分别介绍光热转换材料、基体和水输送通道及其应用于海水淡化的耐盐设计,并简单介绍SDIE的其他应用领域,最后展望其在海水淡化领域待解决的问题和未来研究方向。

光热材料在太阳能海水脱盐中应用的研究进展

用于海水脱盐的太阳能界面蒸发装置因其绿色环保、简单高效以及适用范围广等优点,受到了广泛关注。与传统的体积式蒸发装置不同,太阳能界面蒸发装置将太阳光的收集和蒸汽的产生锁定在空气-水的界面,无需从底部加热整体水来产生蒸汽,极大提高了能源利用效率。本文详细介绍了太阳能界面水蒸发装置的重要组成部分——光热材料的光热转换机理、材料种类以及材料的性能;探讨了高效海水净化太阳能蒸发装置的设计策略(增强光吸收、充足水供应、耐盐排盐等)。在此基础上,总结了基于界面蒸发中的太阳能蒸发装置的研究进展,展望了新型太阳能蒸发装置在海水净化领域的发展前景。