Sun Illumination Research Articles

A comprehensive simulation study of multi-junction solar cell

This study conducts comprehensive simulation analysis of typical triple-junction solar cells using Silvaco ATLAS. Initially, modeling and simulation of the typical triple-junction solar cells under the AM1.5 solar spectrum at 300 K are performed to characterize various performance parameters of the cells under one sun illumination. Subsequently, the impact of the thickness of the top and middle cell layers on the efficiency of the cells is analyzed. Additionally, the influence of doping concentration errors in individual sub-cells on the overall power deviation of the cells is investigated. Moreover, Al0.9Ga0.1As is employed to replace AlInP as the top FSF (Front Surface Field). Furthermore, the study analyzes the variation of internal radiation efficiency of the top and middle sub-cells of the solar cells with concentration factor and bias voltage. Finally, an assessment is made on the effects of different positions and densities of interface defects, as well as the introduction of class-acceptor Gaussian distribution state levels induced by defects, on the performance of the solar cells. The results indicate that this study provides valuable insights for optimizing multi-junction solar cells and analyzing internal physical phenomena.

Black Silver-Decorated liquid metal nanofillers coupled with Glycerol-Modified hydrogel composites for high efficiency solar steam generation and thermoelectric conversion

Solar-driven interfacial evaporation (SDIE) holds great potential in alleviating global freshwater scarcity, which requires the design of efficient energy conversion devices. Herein, a quadruply engineered hydrogel-based evaporator is developed based on multipath regulation of the four key processes involved in SDIE, i.e., heat generation, energy utilization, water transportation, and evaporation. Surface-tailored liquid metal nanoparticles (EGaIn@Ag NPs) with a high photothermal conversion efficiency (PCE) of 30.4 % serve as the nanofiller to produce heat efficiently. Vertically aligned microchannels are constructed in the poly(vinyl alcohol) (PVA) hydrogel through directional freezing to accelerate water transportation. Glycerol is introduced to the PVA matrix to synergistically a) prevent heat loss from the interface to bulk water, and b) modulate the bonding state of water in the hydrogel to reduce the vaporization enthalpy. Such an elaborate design achieves a rather high evaporation rate of 3.26 kg m−2h−1 under 1 sun illumination. The hydrogel evaporator (EGaIn@Ag/PVAG) is applicable in treating real seawater and dye-contaminated sewages, showing favorable desalination durability and self-cleaning property. The synergistic design also imparts the hydrogel with thermoelectric power generation capabilities. This work offers a new insight into the synergistic design of SDIE devices, which is expected to inspire innovations in solar energy conversion and utilization.

Ginseng‐Bioinspired 3D Photothermal Evaporator for Efficient Seawater Desalination Using Conjugated Microporous Polymer

AbstractPhotothermal conversion technology presents a promising approach for harnessing solar energy to facilitate seawater desalination. However, salts will accumulate on the surface of the photothermal conversion structure during seawater desalination, which hinders solar energy absorption. Meanwhile, the photothermal conversion structure directly immersing in a large water body results in a large heat dissipation loss. Both factors impair solar energy conversion and water steam generation. To address the issues, inspired by a ginseng plant (with a trunk‐to‐branch water supply system), a 3D cotton‐based photothermal evaporator with tunable water supply is facilely designed herein via simple cloak‐weaving of a porphyrin‐based conjugated microporous polymer (PPCMP) as the photothermal conversion material. The as‐designed 3D cloak‐like photothermal evaporator achieves an equilibrium between the water supply flux and evaporation rate via optimizing PPCMP weaving and the water path. As a result, a high evaporation rate of 2.81 kg m−2 h−1 and photothermal conversion efficiency of 155% are obtained under 1 sun illumination. The findings underline the importance of 3D porous organic polymer‐based fabrics as effective media for harnessing solar energy and highlight their potential for seawater desalination.

Hydrovoltaic Electricity Generation from Potato Carbon Cake: Using an Interconnected Porous Solar Steam Generator

AbstractIntegrating two advanced techniques, such as solar thermal evaporation (STE) for freshwater production and hydrovoltaic (HV) for electricity generation, makes a considerable attempt to attain basic energy needs. Here in this work, a crisscross porous carbonized ethanol‐treated potato cake as a hydrovoltaic device (CHV) is fabricated. CHV device is a highly stable, portable, eco‐friendly device with a maximum output voltage of 0.23 V and current of 5 µA under ambient conditions. This is further raised to 0.5 V when exposing 1 sun illumination (1 kW m2). Voltage studies are done by varying the wind flow, relative humidity, and bulk water temperature to confirm the device's HV property and dependent factors. The potential application of the device is tested by glowing an LED light connected with 5 CHV devices in series. It is continuously delivered output till the bulk water is dry. The shelf‐life ability of CHV is also analyzed after 1 year of usage and provided nearly the same outcome. Therefore, this single device with dual‐energy harvesting gives a significant solution to society's energy and water crisis for a better tomorrow.

Surface hydration of trimethylamine N–oxide/perovskites hybrid aerogel facilitates anti–fouling solar desalination and seawater electrocatalysis

Developing active and stable electrocatalysts for oxygen evolution reaction is of great significance to generate oxygen and hydrogen by seawater electrolysis, which however remains some issues that high energy consumption and chloride corrosion. Here we pioneered a polymer/inorganic hybrid engineering strategy for achieving excellent salt resistance solar evaporation and oxygen evolution performance (OER). The La0.9Sr0.1CoO3/nickel foam–cellulosic aerogel (LSC1/NF–CA) was synthesized by engineering Trimethylamine N–oxide (TMAO) polymer brush onto the surface of hybrid aerogels composed of La0.9Sr0.1CoO3/Ni foam (LSC1/NF) and cellulose/polyvinyl alcohol, which has good hydrophilic features, intrinsic solar capture capacity, and stable OER performance in seawater. Benefiting from the synergy of solar desalination with surface hydration effect of TMAO, the LSC1/NF–CA presents a superior catalytic activity, requiring a lower overpotential of 341 mV and a tafel slope of 58.2 mV dec−1 at 10 mA cm−2 under 6.0 sun illumination. Our results establish a new strategy that can guide the design of stable and efficient polymer/inorganic hybrid catalysts, which shows a promising prospect as alternatives to noble metal–based catalysts for seawater splitting.

Mobile iodides capture for highly photolysis- and reverse-bias-stable perovskite solar cells.

For halide perovskites that are susceptible to photolysis and ion migration, iodide-related defects, such as iodine (I2) and iodine vacancies, are inevitable. Even a small number of these defects can trigger self-accelerating chemical reactions, posing serious challenges to the durability of perovskite solar cells. Fortunately, before I2 can damage the perovskites under illumination, they generally diffuse over a long distance. Therefore, detrimental I2 can be captured by interfacial materials with strong iodide/polyiodide (Ix-) affinities, such as fullerenes and perfluorodecyl iodide. However, fullerenes in direct contact with perovskites fail to confine Ix- ions within the perovskite layer but cause detrimental iodine vacancies. Perfluorodecyl iodide, with its directional Ix- affinity through halogen bonding, can both capture and confine Ix-. Therefore, inverted perovskite solar cells with over 10 times improved ultraviolet irradiation and thermal-light stabilities (under 85 °C and 1 sun illumination), and 1,000 times improved reverse-bias stability (under ISOS-V ageing tests) have been developed.

Combined effect of grooves and nanoflower structured Co3O4 coating on bamboo wood for highly efficient solar steam generation at indoor and outdoor conditions.

Currently, interfacial solar steam generation (ISSG) in desalinating water has become very popular for obtaining purified water from polluted water. However, finding an efficient evaporator with low cost is a challenging task for researchers. In this work, we introduce natural bamboo wood (BW) that acts as an interfacial evaporator for obtaining purified water. Four different wood evaporators namely, flat wood (BW-FW), two-cut grooved wood (BW-2G), four-cut grooved wood (BW-4G), and four-cut grooved with Co3O4-coated wood (BW-4G/Co3O4) are used to study the mass loss (ML), evaporation rate (ER), and evaporation efficiency (EY). From the observations, BW-4G/Co3O4 gives an admirable ML, ER, and EY of 4.4 g, 3.366 kg m-2 h-1, and 91.34% under 1 sun illumination for 60 min. Also, the BW-4G/Co3O4 evaporator is kept under natural sun illumination. It achieves 17.8 g of ML, 1.92 kg m-2 h-1 of ER, and 76% of EY respectively under 604.762 W/m2 solar illumination for 8 h. The reasons for the observed results are as follows: (i) the presence of grooves increases the exposing area for solar illuminations, (ii) super hydrophilicity nature of wood gives continuous replenishment of water from the bottom to the evaporative surface, (iii) the excellent salt rejection property of wood aids in continuous water transportation without salt accumulations. As a result of the condensed seawater samples, the ion concentrations (zinc, magnesium, cadmium, lead, copper, and sodium) come under WHO standards. Consequently, it gives better dye water separation from polluted water.

Unravelling the Photoelectrochemical Water Splitting of Nanometer-Thick Carbon Nitride Layer.

Matching the thickness of the graphitic carbon nitride (CN) nanolayer with the charge diffusion length is expected to compensate for the poor intrinsic conductivity and charge recombination in CN for photoelectrochemical cells (PEC). Herein, the compact CN nanolayer with tunable thickness is in situ coated on carbon fibers. The compact packing along with good contact with the substrate improves the electron transport and alleviates the charge recombination. The PEC investigation shows CN nanolayer of 93nm-thick yields an optimum photocurrent of 116µAcm-2 at 1.23V versus RHE, comparable to most micrometer-thick CN layers, with a low onset potential of 0.2V in 1m KOH under 1 sun illumination. This optimum performance suggests the electron diffusion length matches with the thickness of the CN nanolayer. Further deposition of NiFe-layered double hydroxide enhanced the surface water oxidation kinetics, delivering an improved photocurrent of 210µAcm-2 with IPCE of 12.8% at 400nm. The CN nanolayer also shows extended potential in PEC organic synthesis. This work experimentally reveals the PEC behavior of the nanometer-thick CN layer, providing new insights into CN in the application of energy and environment-related fields.

Comparative study of natural and synthetic dyes in DSSCs: An experimental and computational approach

This study explores the natural and synthetic dyes as sensitizers for dye-sensitized solar cells (DSSCs). Anthocyanin dye extract (PG) from pomegranate (Punica granatum) fruit, betanin pigment (BR) from beetroot (Beta vulgaris), and the commercially available organic dye, Rose Bengal (RB), were investigated as sensitizers for DSSCs and their photovoltaic performances were recorded. Density functional theory (DFT) and time-dependent DFT (TD-DFT) studies have also been performed in order to get insight into the photophysical and photoelectrochemical properties. The overall efficiencies (η) of 0.34%, 0.30%, and 0.25% were obtained for the PG, BR, and RB dyes under 1 sun illumination, respectively. The results infer that PG dye would act as a promising photo-sensitizer for DSSCs as compared to BR and RB sensitizers, which may be due to better interaction between anthocyanin molecule of pomegranate extract and TiO2.

Multifunctional Super-Hydrophilic MXene/Biomass Composite Aerogel Evaporator for Efficient Solar-Driven Desalination and Wastewater Treatment.

Solar-driven interfacial evaporation is recognized as a sustainable and effective strategy for desalination to mitigate the freshwater scarcity issue. Nevertheless, the challenges of oil contamination, salt accumulation, and poor long-term stability of the solar desalination process limit its applications. Herein, a 3D biomass-based multifunctional solar aerogel evaporator is developed for water production with fabricated chitosan/lignin (CSL) aerogel as the skeleton, encapsulated with carbonized lignin (CL) particles and Ti3C2TiX (MXene) nanosheets as light-absorbing materials. Benefitting from its super-hydrophilic wettability, interconnected macropore structure, and high broadband light absorption (ca. 95.50%), the prepared CSL-C@MXene-20mg evaporator exhibited a high and stable water evaporation flux of 2.351kg m-2 h-1 with an energy conversion efficiency of 88.22% under 1 Sun (1kW m-2) illumination. The CSL-C@MXene-20mg evaporator performed excellent salt tolerance and long-term solar vapor generation in a 3.5wt.% NaCl solution. Also, its super-hydrophilicity and oleophobicity resulted in superior salt resistance and anti-fouling performance in high salinity brine (20wt.% NaCl) and oily wastewater. This work offers new insight into the manufacture of porous and eco-friendly biomass-based photothermal aerogels for advanced solar-powered seawater desalination and wastewater purification.

Carboxymethylcellulose sodium-derived carbon aerogels for solar-driven water purification

Recycling polluted water via different techniques has become one of the most feasible ways to solve the freshwater crisis. We describe a novel method to prepare reusable and efficient photothermal energy conversion materials for water purification. Using crosslinked xerogels as precursor, the porous and interconnected carboxymethylcellulose sodium-derived carbon aerogels (abbreviated as CCAs) with good hydrophilic performance and strong light absorption capability are firstly fabricated through pyrolysis. Photothermal measurement results show that CCA15 exhibit excellent solar steam generation rate of 2.31 kg m−2 h−1 with high light-to-vapor conversion efficiency of 95.9% under 1 sun illumination. In addition, the feasible application of CCA15 for efficient water purification under 1 sun irradiation using a homemade water treatment device has been demonstrated successfully. The as-prepared CCAs shown in here can be a continuable solution to mitigate the global freshwater crisis.

Integrating physical model and image simulations to correct topographic effects on surface reflectance

Topography complicates the illumination distribution over rugged terrains and hinders the applications of surface reflectance data over mountainous areas. Topographic correction is an essential process to remove the topographic effects in surface reflectance data. This study proposed a Physical model and image Simulation-based topographic Correction method (PSC) for atmospherically corrected surface reflectance images. In contrast with traditional methods, the proposed approach explicitly estimates the illumination distribution over rugged terrains based on image information and then corrects the topographic effects following physical laws. The proposed method was validated and compared with existing well-performed topographic correction methods, including path length correction (PLC), sun-canopy-sensor correction with c factor (SCSC), C correction (CC), and statistical empirical correction (SE). Simulated and satellite data obtained at different times and geolocations are used for evaluation and comparison. The results demonstrated that most existing methods face challenges in removing the biases induced by topography in surface reflectance images. The PLC method failed to obtain reasonable results for faint illumination conditions when the sun zenith angle is high. SE showed relatively poor performance in terms of physical consistency and outlier percentage. Besides, all the traditional methods failed in the correction of cast shadow regions. Comparably, our method consistently demonstrated superior performance in physical consistency, cast shadow correction, and outlier percentage across various regions, encompassing different sun zenith angles and illumination conditions. The proposed method offers an effective and physically consistent approach for the topographic correction of surface reflectance images, facilitating multi-temporal applications over mountainous areas.

Polyhedral Oligomeric Sesquioxane Cross-Linked Chitosan-Based Multi-Effective Aerogel Preparation and Its Water-Driven Recovery Mechanism.

The use of environmentally friendly and non-toxic biomass-based interfacial solar water evaporators has been widely reported as a method for water purification in recent years. However, the poor stability of the water transport layer made from biomass materials and its susceptibility to deformation when exposed to harsh environments limit its practical application. To address this issue, water-driven recovery aerogel (PCS) was prepared by cross-linking epoxy-based polyhedral oligomeric silsesquioxane (EP-POSS) epoxy groups with chitosan (CS) amino groups. The results demonstrate that PCS exhibits excellent water-driven recovery performance, regaining its original volume within a very short time (1.9 s) after strong compression (ε > 80%). Moreover, PCS has a water absorption rate of 2.67 mm s-1 and exhibits an excellent water absorption capacity of 22.09 g g-1 even after ten cycles of absorption-removal. Furthermore, a photothermal evaporator (PCH) was prepared by loading the top layer with hydrothermally reacted tannins (HAs) and Zn2+ complexes. The results indicate that PCH achieves an impressive evaporation rate of 1.89 kg m-2 h-1 under one sun illumination. Additionally, due to the antimicrobial properties of Zn2+, PCH shows inhibitory effects against Staphylococcus aureus and Escherichia coli, thereby extending the application of solar water evaporators to include antimicrobial purification in natural waters.

Robust and multifunctional MXene/rGO composite aerogels toward highly efficient solar-driven interfacial evaporation and wastewater treatment

Given the ever-growing global water resource crisis, exploiting multifunctional materials featuring with high interfacial solar steam generation efficiency and good purification capability to achieving seawater desalination and wastewater treatment simultaneously are highly desired, yet it still remains a huge challenge to date. Herein, robust and multifunctional MXene/rGO (MRGA) and polydopamine & chitosan @ MRGA (CS&PDA@MRGA, CPM) three-dimensional composite aerogels with distinct interconnected cellular architecture were developed via a facile ice template-assisted chemical reduction self-assembly technology and subsequent sequential deposition modification. Due to the favorable graphene oxide-assisted assembly behavior, the resultant aerogels displayed a desirable mechanical robustness along with an excellent lightweight property. Benefiting from the strong electrostatic interaction deriving from aerogel surface moieties and dye molecules, MRGA-12 exhibited a prominent adsorption capability towards various dyes and achieved a superb adsorption capacity of up to 396.05 mg/g for malachite green (MG). Moreover, by virtue of the synergistic effect between the intentionally regulated low reduction degree of rGO and the integration of PDA and CS, CPM-12 achieved a dramatically reduced evaporation enthalpy of water from 2256 to 1617.18 J/g. Accordingly, this distinct feature resulted in an extraordinary solar-driven interfacial evaporation performance with a remarkable evaporation rate of 1.86 kg/m2/h and a high evaporation efficiency of 83.28 % under 1 sun illumination. Therefore, together with the terrific oil/water separation capability, these novel MXene-based aerogels hold a great potential for high-performance solar-driven interfacial evaporation and wastewater treatment.

Phase-stable wide-bandgap perovskites enabled by suppressed ion migration

Wide-bandgap (>1.7 eV) perovskites suffer from severe light-induced phase segregation due to high bromine content, causing irreversible damage to devices stability. However, the strategies of suppressing photoinduced phase segregation and related mechanisms have not been fully disclosed. Here, we report a new passivation agent 4-aminotetrahydrothiopyran hydrochloride (4-ATpHCl) with multifunctional groups for the interface treatment of a 1.77-eV wide-bandgap perovskite film. 4-ATpH+ impeded halogen ion migration by anchoring on the perovskite surface, leading to the inhibition of phase segregation and thus the passivation of defects, which is ascribed to the interaction of 4-ATpH+ with perovskite and the formation of low-dimensional perovskites. Finally, the champion device achieved an efficiency of 19.32% with an open-circuit voltage (VOC) of 1.314 V and a fill factor of 83.32%. Moreover, 4-ATpHCl modified device exhibited significant improved stability as compared with control one. The target device maintained 80% of its initial efficiency after 519 h of maximum power output (MPP) tracking under 1 sun illumination, however, the control device showed a rapid decrease in efficiency after 267 h. Finally, an efficiency of 27.38% of the champion 4-terminal all-perovskite tandem solar cell was achieved by mechanically stacking this wide-bandgap top subcell with a 1.25-eV low-bandgap perovskite bottom subcell.

Effective solar-driven evaporators with urchin-like CuO particles and directional polyvinylidene fluoride scaffolds via directional dimethyl sulfoxide crystallization and non-solvent induced phase separation

Solar-driven evaporators with vertical channels usually exhibit excellent desalination due to the fast water transportation and excellent salt tolerance, which are often fabricated via a directional liquid nitrogen-assisted ice templating method and freeze-drying process. However, they are reliant on a very limited number of water-soluble polymers and hydrophilic inorganic materials, and the freeze-drying process costs a long time and much energy. A highly efficient and straightforward process for the fabrication of solar-driven evaporators with directional channels from water-insoluble materials is urgent. Here, water-insoluble polyvinylidene fluoride was dissolved in dimethyl sulfoxide (DMSO), and then the solution was engineered to PVDF scaffolds by the combination of directional DMSO crystallization with the commonly porous membrane formation method of non-solvent (water) induced phase separation. The result is the creation of oriented perpendicular pores to the surfaces and framberry-like microparticles on the pore walls. After the in situ deposition of urchin-like CuO particles with high solar adsorption on PVDF scaffolds, PVDF/CuO solar-driven evaporators have been successfully constructed. The evaporate rate depends on the PVDF content and CuO loading. Briefly, PVDF/CuO evaporators fabricated from high PVDF content of more than 3 wt% have low porosity, slow water supply, and poor hydrophilicity, resulting in a low evaporate rate and high evaporation enthalpy. The optimized 3D PVDF/CuO evaporator (V3-9 h) with a PVDF content of 3 wt% and CuO loading of 31.3 ± 1.6 wt% has a high pure water evaporation rate of 3.2 ± 0.2 and 3.5 ± 0.3 kg m-2h−1 under sun illumination at 1 and 2 kW m−2, respectively. And the evaporation enthalpy is as low as 1083.8 ± 25.5 J/g, 55 % lower than pure water. Moreover, the sample exhibits a similar evaporation rate in 3.5 wt% NaCl solution because the verticle channels endow the evaporator with excellent salt tolerance. The facile and scalable fabrication process of solar-driven evaporators with directional channels will greatly boost the development of cost-effective desalination.

Biomimetic Design of 3D Fe3O4/V-EVOH Fiber-Based Self-Floating Composite Aerogel to Enhance Solar Steam Generation Performance.

An interfacial solar steam generation evaporator for seawater desalination has attracted extensive interest in recent years. Nevertheless, challenges still remain in relatively low evaporation rate, unsatisfactory energy conversion efficiency, and salt accumulation. Herein, we have demonstrated a biomimetic bilayer composite aerogel consisting of bottom hydrophilic and vertically aligned EVOH channels and an upper hydrophobic conical Fe3O4 array. Thanks to the design merits, the 3D Fe3O4/V-EVOH evaporator exhibits a high evaporation rate of ∼2.446 kg m-2 h-1 and an impressive solar energy conversion efficiency of ∼165.5% under 1 sun illumination, which is superior to those of state-of-the-art evaporators reported so far. Moreover, the asymmetrical wettability not only allows the evaporator to self-float on the water but also facilitates the salt ion diffusion in the channels; thus, the evaporator shows no salt crystals on its surface and only a 6% decrease in evaporation performance even after the salt concentration increases from 0 to 10.0 wt %.

Halide Engineering in Mixed Halide Perovskite-Inspired Cu2AgBiI6 for Solar Cells with Enhanced Performance.

Cu2AgBiI6 (CABI) is a promising perovskite-inspired absorber for solar cells due to its direct band gap and high absorption coefficient. However, the nonradiative recombination caused by the high extrinsic trap density limits the performance of CABI-based solar cells. In this work, we employ halide engineering by doping bromide anions (Br-) in CABI thin films, in turn significantly improving the power conversion efficiency (PCE). By introducing Br- in the synthetic route of CABI thin films, we identify the optimum composition as CABI-10Br (with 10% Br at the halide site). The tailored composition appears to reduce the deep trap density as shown by time-resolved photoluminescence and transient absorption spectroscopy characterizations. This leads to a dramatic increase in the lifetime of charge carriers, which therefore improves both the external quantum efficiency and the integrated short-circuit current. The photovoltaic performance shows a significant boost since the PCE under standard 1 sun illumination increases from 1.32 to 1.69% (∼30% relative enhancement). Systematic theoretical and experimental characterizations were employed to investigate the effect of Br- incorporation on the optoelectronic properties of CABI. Our results highlight the importance of mitigating trap states in lead-free perovskite-inspired materials and that Br- incorporation at the halide site is an effective strategy for improving the device performance.

Unveiling and Overcoming Instabilities in Perovskite Solar Cells Induced by Atomic‐Layer‐Deposition Tin Oxide

Atomic layer deposition of tin oxide (ALD–SnOx) has emerged as a promising buffer/protection layer, often replacing bathocuproine (BCP) in applications such as semitransparent and tandem devices. However, the long‐term stability and underlying degradation mechanisms of perovskite solar cells (PSC) incorporating ALD–SnOx remain elusive. Herein, the long‐term stability of PSCs featuring an ALD–SnOx buffer layer is systematically investigated. Intriguingly, it is observed that cells with ALD–SnOx exhibit heightened susceptibility to severe degradation, surpassing even the degradation levels observed with BCP under humid conditions. Through an extensive analysis employing X‐ray photoelectron spectroscopy and X‐ray diffraction, it is unveiled that ALD–SnOx triggers a phase transition in the perovskite when exposed to moisture, transitioning from the black cubic phase to the yellow delta phase, despite the presence of a thin layer of fullerene between the SnOx and the perovskite. Replacing ALD–SnOx with ALD–AlOx as a buffer layer emerges as a transformative strategy, effectively bolstering the humidity and thermal stability of the cells, without affecting device efficiency. The optimized ALD–AlOx‐buffered device exhibits a high efficiency of 24.61% and maintains 88% of its initial efficiency after maximum power point tracking under 1 sun illumination for 1350 h at 65 °C in ambient air when encapsulated.

Same volume, larger output: 3D trapezoidal multi-interface solar evaporator for concentrated seawater desalination and wastewater treatment

With the scarcity of freshwater resources, solar desalination of seawater is a promising strategy for freshwater production. Compared to 2D evaporators with limited evaporation area, 3D evaporators can increase the evaporation area. However, traditional 3D evaporators cannot fully utilize the internal space of the evaporator for evaporation. In this study, a 3D trapezoidal multi-interface evaporator (Evap1), which composed of superhydrophilic sponges and superhydrophobic sponges arranged by alternate permutation for making full use of the inside structure of the evaporator to expand the actual evaporation area and achieve effective thermal management, were developed. The selective water transport channels and heat transfer channels were constructed by alternate permutation of hydrophilic and hydrophobic sponges in Evap1, while the top trapezoidal structure prevented heat from accumulating on the top surface of Evap1, which can enhance the efficiency of photothermal conversion. The Evap1 exhibited excellent evaporation rate of 3.6 kg m−2 h−1 under 1 sun illumination, and the evaporation rate was almost unchanged in brine with 20 wt% concentration for 8 h working. In addition, the Evap1 can achieve efficiently purificaiton of waste water containing dye, and the potential practical application of Evap1 was further proved by repeated and outdoor evaporation experiments.