Solar Absorption Research Articles

In-situ construction of novel Sb2(S,Se)3/CdSe S-scheme heterojunction with enhanced photoelectrochemical performance

Abstract Antimony selenosulfide (Sb2(S,Se)3) was considered to have great potential for photoelectrochemical (PEC) water splitting applications due to its excellent chemical stability, good light absorption, abundant reserves and non-toxicity. However, Sb2(S,Se)3 faces some limitations in the field of PEC, such as the serious recombination problem of photogenerated carriers. Therefore effectively restraining its deep-level defects is the crucial for enhancing its photoelectrochemical properties. In this paper, We successfully fabricated Sb2(S,Se)3/CdSe S-scheme heterojunction via one-step hydrothermal method, which improves its solar absorption capacity, facilitates efficient carrier separation. And, Sb2(S,Se)3/CdSe S-scheme heterojunction can suppress the adverse effects of deep-level defects on the PEC performance of Sb2(S,Se)3. Under simulated solar irradiation, the light current density can reach 4.02 mA cm2 (33.5 times that of monomeric Sb2(S,Se)3) at 1.23 VRHE, accompanied by low initial voltage and extremely high surface charge injection efficiency. This study is of great significance for the application of Sb2(S,Se)3 in the PEC field.

Bioinspired Spectrally Selective Phase‐Change Composites for Enhanced Solar Thermal Energy Storage

AbstractIntegrating solar thermal conversion with phase change materials (PCMs) offers a promising pathway for continuous thermal energy generation with a zero‐carbon footprint. However, substantial infrared radiation losses at elevated temperatures often hinder the efficiency of such integrated systems. Inspired by the thermoregulation mechanisms of polar bears, this work introduces composite PCMs with spectrally selective absorption to enhance solar thermal energy storage efficiency. These composite phase change materials (CPCMs), featuring densely packed SiC ceramic grains with high porosity, exhibit a thermal conductivity of up to 14 W m−1 K−1 and an energy storage density of 195.1 kJ kg−1. The incorporation of nanoparticle‐coated foil induces a plasmonic effect that increases solar absorptivity to 90.57% and reduces infrared emissivity from 71.94% to 7.47%. Consequently, the solar thermal storage efficiency is significantly increased from 54.56% to 81.65% at 500 K, effectively addressing the challenges associated with high‐temperature solar thermal storage. Additionally, the low infrared emissivity of the c (PNC), combined with the inherent heat absorption properties of PCMs, enables infrared stealth functionality. These multifunctional CPCMs demonstrate considerable potential for advancing high‐temperature solar thermal storage technologies and other heat‐related applications.

Carbon nanotube heat absorber for efficient direct-heating of liquid tin in a solar receiver

A new approach that use vertically-aligned carbon nanotubes (VACNT) as heat absorbers is proposed for efficient direct solar heating of liquid tin in a solar receiver integrated with beam-down optics. Plate-type CNT heat absorbers were prepared by adjusting the concentration of CNTs in the processing solvent m-cresol. The prepared CNT absorber exhibited an increase in bulk density and the formation of a densely packed nanotubes skeleton with a higher CNT concentration in m-cresol. Thermal conductivity, a key design factor for solar absorbers, showed a stronger correlation with skeletal density than with bulk density. Heat absorption characteristics of the solar liquid tin receiver (50 mm-i.d., 60 mm-high) with the CNT absorbers integrated with a Fresnel lens (0.98 m i.d.) were determined. The tin temperature in the receiver with the CNT absorber reached a maximum of 728 °C. Bare tin exhibited system efficiency of 27.7 % and receiver efficiency of 38.3 %, but tin heating through the CNT plates exhibited system efficiency of up to 48.4 % and receiver efficiency of 64.3 %, showing a system heat absorption rate 1.75 times higher. The thermal absorption efficiency was proportional to the skeletal density of the plates, and the thermal absorption of the system was dominated by the efficient transfer of absorbed heat in the energy absorption region. The energy flow and heat loss in the receiver system were analyzed. Although the bare tin receiver exhibited a high heat loss of 27.1 % owing to the low emissivity or high reflectivity of the tin surface, the heat loss in the CNT absorber plates with high absorptivity was only 0.9 %. The flat plate-shaped transmission window in the receiver caused significant reflective heat loss and convective heat loss owing to head-on wind. Based on the energy flow analysis, improvement approaches for enhancing the thermal efficiency of the proposed receiver system are suggested.

Comparative characterizations of plant and mineral dye as potential photosensitizer in Dye-Sensitized Solar Cell

The advent of dye-sensitized solar cells (DSSC) has expansively seen more studies as an alternative to silicon-based and thin-film solar cells due to their simple structure and relatively low production cost. In dye-sensitized solar cells, the dye is one of the major components for high power conversion efficiencies. The extracted dyes were characterized by powder x-ray diffraction, x-ray fluorescence, Scanning electron microscopy, UV-visible spectroscopy, and Gas Chromatography-Mass spectrometry analysis. The structure of the mineral dye contains constituents that enhance better absorption of solar radiation for use in a Dye-Sensitized Solar Cell (DSSC). The calcium and iron content of the mineral dye studied as revealed by the mineralogical analysis done using the powder x-ray diffraction (XRD) and the x-ray fluorescence (XRF) suggest this. These metals serve as bounding complexes to other organic components in the dye, like in the case of Ruthenium complexes dye for efficient absorption of solar radiation, especially in the visible light region. The functional groups present in the dye also confirm what favors good absorption of solar radiation for DSSC application. The Organic chemical compositions present in the mineral dye which were obtained by the Gas Chromatography-Mass spectrometry analysis also confirm the functional groups of carbonyl, Amine, and hydroxyl revealed by FTIR, which were responsible for solar radiation absorption. There are strong absorption narrow bands in the visible region with peaks at around 424 nm (2.903 a.u) and 486 nm (2.973 a.u). Optical band gaps of 1.66 eV and 2.27 eV for the mineral dye and plant dye respectively, were obtained. The properties of the dyes studied give potential substitutes to the relatively expensive ruthenium-based dyes for use in DSSC fabrication.

Modulating intramolecular charge transfer via π-d conjugative effect in coordination polymers toward photo-thermo-electric conversion

The prospect of harnessing sunlight to generate cost-effective heat and electricity presents a captivating opportunity to address water scarcity and electricity shortages. Photothermal materials with a broad absorption spectrum are indispensable for effectively harnessing solar energy and converting it into heat/electricity. Herein, we developed an intramolecular charge transfer strategy via conjugated effect to regulate solar absorption and photothermal conversion ability of M-DABDT (M = Fe/Co/Ni/Cu/Zn, DABDT = 2,5-diaminobenzene-1,4-dithiol), overcoming a common limitation of narrow absorption and low photothermal efficiency in traditional metal-organic assemblies. The density functional theory calculations reveal that altering transition metal ions induces the structural torsion of organic linkers, resulting in a significant change in dihedral angle from 89.96° to 2.57°. The structural change significantly facilitates the charge transfer and electron relaxation, ultimately promoting the conversion of light to heat. Under one sun irradiation, the maximum temperature of Fe-DABDT can reach approximately 92.5 ℃. More significantly, the integration of M-DABDT CPs and thermoelectric devices under normal solar irradiation results in an extraordinary open circuit voltage (238 mV) and maximum power density (364.5 μW m−2), processing a peak output voltage density of 76.9 V m−2 at 11:00 a.m. in the presence of outdoor sunlight. This strategy presents an avenue for developing metal-organic solar absorbers for photo-thermo-electric conversion systems.

Radiative cooling materials prepared by SiO2 aerogel microspheres@PVDF-HFP nanofilm for building cooling and thermal insulation

Radiative cooling is promising in meeting the current global demand for green sustainable development. However, the effective cooling of the existing radiant cooler will be limited due to the serious solar energy absorption and poor thermal insulation performance on the cold side. To addresss these issues, we propose herein a novel composite material of silicon dioxide (SiO2) aerogel microspheres combined with polyvinylidene fluoride-cohexafluoropropylene (PVDF-HFP) nanofiber membrane, in which SiO2 aerogel microspheres are firstly synthesized by sol-gel method and then incorporated into PVDF-HFP nanofiber membrane to give radiative cooling performance. As we expected, the molecular vibration characteristics of PVDF-HFP nanofiber membrane and the phonon polarization resonance of Si-O-Si bond in the transparent window can enhance the infrared emissivity of the membrane surface. In addition, the high porosity and the mesoporous structure formed by the interconnection of nano-network skeletons of SiO2 aerogel microspheres determine its excellent thermal insulation performance. The as-prepared material displays that the average solar reflectance of the composite membrane is 96.07 % and the average infrared emissivity of the atmospheric window is 94.95 %. Notably, when the average solar radiation intensity is 885.56 W•m−2, the passive radiative cooling temperature during the day can reach 11.2 °C. Furthermore, this material has excellent self-cleaning and thermal insulation performance, making it a potential radiant cooling candidate in many fields.

A new type of pentagonal structure HgS2 monolayer with abundant active sites and low Gibbs free energy for photocatalytic water splitting

Discovery of new two-dimensional (2D) materials not only has important fundamental research significance but also has promising application prospects. Through systematic structure searching combined with density functional theory calculations and simulations, we predict a new 2D monolayer HgS2 material featuring with a previously unreported type of pentagonal structure with orthorhombic P21212 symmetry. The penta-HgS2 monolayer shows good thermal, thermodynamic, mechanical and dynamic stabilities, exhibiting ferroelastic phase transition with an ultralow switching energy barrier (about 1 meV/atom), high ultimate strength of 12 N/m, moderate indirect band gap of 2.25 eV. In addition, the penta-HgS2 monolayer shows significantly anisotropic carrier mobility with a large anisotropy ratio of 98.5 along the y direction. More importantly, the penta-HgS2 monolayer exhibits abundant catalytic active sites, low Gibbs free energy (ΔGH ranging from 0.656 to 1.687 eV) for hydrogen evolution reactions, excellent solar light absorption capacity (∼105 cm−1) with the solar-to-hydrogen efficiency reaching up to 11.83%. The excellent ultimate tensile ability and the ultralow ferroelastic phase transition energy barrier implies penta-HgS2 monolayer material can be used to manufacture flexible mechanical and nanoelectronic devices. The suitable band edge alignments, ultrahigh carrier mobility anisotropy, high catalytic activity and excellent visible light adsorption performance indicate that penta-HgS2 monolayer is a promising candidate photocatalyst for high-performance photocatalytic water splitting. The present work not only supplements a new member to the 2D pentagonal structure material family, but also points out its promising applications in nanoscale devices and photocatalytic hydrogen productions.

De novo Cu-MOF@CNS nanocomposite coated on a cotton fibrils framework for sustainable solar-driven desalination.

Environmental researchers are extremely concerned about addressing the declining availability of drinking water, which is a critical issue in many nations. Solar-driven desalination is an emerging and pioneering renewable approach to reduce potable water scarcity that is suitable for remote locations, developing countries, and disaster zones as it does not require additional energy supply. However, there are still issues with the scalable preparation of photothermal materials, such as achieving low cost and widening the assortment of useful applications. Conventional carbon- and metal-based absorbers are intricate and fragile, which make them difficult to install and transport in places with minimal infrastructure. Thus, a universal process for creating adaptable solar evaporators is sorely required. Herein, we have come up with a holistic approach using a solar absorber (GJ-01(Cal)) derived from a Cu-MOF (HKUST-1) and carbon nanosheets (CNSs) for generating potable water from saline water using solar radiation. The as-synthesized material provides high-performance photothermal water evaporation when illuminated under solar irradiation at the air-water interface. Moreover, its porous structure, high photothermal conversion efficiency, rapid water flow, and heat insulation make it appropriate for saline water desalination. CNS play a pivotal role in improving the photothermal features of the solar absorber (GJ-01(Cal)) in terms of conjugation to promote Cu(0) species and pyrrolic nitrogen (P-N) amplification and thereby enrich the p-type nature of the absorber's triphasic configuration. With these photothermal factors, the localised surface plasmon resonance (LSPR) of electrons increases and achieves high solar spectrum absorption. The GJ-01(Cal) was further coated on porous cotton fibrils (CF) that regulate photothermal interfacial evaporation (PTIE) by allowing water transportation via capillary action. This assemblage of the nanocomposite on CF efficiently evaporates water at a higher surface temperature of ∼47 °C under one solar illumination, achieving 4.23 kg m-2 h-1 of evaporation flux and 96.5% light-to-heat conversion efficiency. Interestingly, the GJ-01(Cal) coated over CF can be recycled at least 10 times. Additionally, it offers scalable production for higher photothermal efficiency with a flexible substrate as a solar evaporator and is beneficial for society paving new horizons towards a sustainable environment.

A C-modified engineering strategy of porous In2O3 catalysts for point-concentrated solar-driven photothermal CO2 hydrogenation

The solar-driven photothermal CO2 conversion serves as an effective approach for addressing the substantial challenges of energy crises and global environmental issues. In this work, various forms of In2O3 catalysts, including In2O3-c, In2O3-r, In2O3-s, and porous spherical In2O3, along with a C-modified porous spherical In2O3 catalyst (C-In2O3), were successfully synthesized through a hydrothermal method. An in-depth analysis was conducted to evaluate the performance of these catalysts in the point-concentrated solar-driven photothermal CO2 hydrogenation. As a result, the porous C-In2O3 catalyst exhibited a superior CO2 conversion rate of approximately 13.2 % under simulated sunlight irradiation, with a light intensity of 44.6 mW/cm2. Notably, all catalysts demonstrated nearly 100 % selectivity towards CO (CO production rate of around 8.51 mmol gcat−1h−1) during the photothermal catalytic reaction, without any formation of CH4. The outstanding performance of the C-In2O3 catalyst was attributed to the modification of In2O3 band structure by the incorporation of C, which significantly enhanced the intensive solar light absorption of the catalyst. Furthermore, incorporating C into In2O3 substantially augments its basic strength and significantly elevates the quantity of basic sites, thereby endowing it with outstanding CO2 adsorption and conversion capabilities. This work provides a C-modified engineering strategy to design efficient photothermal catalysts for boosting point-concentrated photothermal CO2 hydrogenation.

Synthesis of high-value porous carbon from waste plastics and structure regulation promote solar interface water evaporation

Water scarcity and waste plastics elimination are long-term problems facing sustainable development, and solar interface evaporation to produce clean water is regarded as a promising water treatment technology. Herein, we report on low-cost waste plastic bottles synthetic carbon-based photothermal materials. By KOH activation and perforation, the surface crack structure of porous carbon is formed to facilitate multi-stage reflection of solar light, and significantly improve the solar light absorbance and photothermal conversion ability. Three-dimensional solar evaporators with low thermal conductivity and super hydrophilic wood sponge are fabricated, and the rectangular hole is designed to regulate water movement and prevent heat dissipation. When exposed to 1 sun illumination (1 kW/m2), an evaporation rate of 1.59 kg·m-2·h-1 is achieved, along with an energy conversion efficiency of 88.49 %. In addition, different micro-surface rough structures are constructed to boost the solar light absorption, thereby enhancing the photothermal conversion ability, among which the micro-cone structure increased the evaporation rate to 1.93 kg·m−2·h−1, demonstrating excellent stability over 15 cycles. In the simulated sewage purification process, the removal rate of pollutants is 99.9 %, and the evaporator without obvious salt accumulation in the seawater for 24 h, showing good salt resistance and self-cleaning ability. This research has important reference value for high-value preparation of carbon-based photothermal materials from waste plastics, extraction of clean water and environmental sustainable protection.

Boosting the performance of SnSe-based solar cells through electron and hole transport layers: A qualitative study and perspectives

The SnSe compound is garnering considerable interest as a potential solar absorber for developing highly efficient thin-film solar cells. Using one experimental report as a foundation and employing the one-dimensional solar cell capacitance simulator (SCAPS-1D), we examined the elements that impact the efficiency of solar cells utilizing tin selenide as the base material. The base structure consists of Anode/SnSe/CdS/i-ZnO/ZnO:Al/Cathode. A 0.5 μm thick SnSe film demonstrated an efficiency of 2.51 %. In the initial phase, we optimized the device efficiency to 18.65 % through parameter adjustments, utilizing toxic CdS as a buffer layer. In the subsequent phase, earth-abundant and non-toxic Zn1-xMgxO, SnO2, and TiO2 alternatives were explored as electron transport materials (ETL) to replace CdS. Zn1-xMgxO (with x = 0.1875) exhibited the highest efficiency at 19.03 %. In the final phase, various hole transport materials (HTL) were studied to enhance the SnSe-based solar cell's performance. Among the HTL materials investigated, NiO yielded the best efficiency of 20.59 % when using Zn1-xMgxO (with x = 0.1875) as a buffer layer.

Dual-Mode MXene-Based Phase-Change Composite Towards Enhanced Photothermal Utilization and Excellent Infrared Stealth.

Solar thermal collectors based on phase change materials (PCMs) are important to promote the civilian use of sustainable energy. However, simultaneously achieving high photothermal efficiency and rapid heat transfer of the PCM carrier typically involves a high proportion of functional materials, contradicting a satisfying energy storage density. In this work, a surface-engineered anisotropic MXene-based aerogel (LMXA) integrated with myristic acid (MA) to produce phase change composites (LMXA-MA) is reported, in which the laser-treated surface composed of the hierarchically-structured TiO2/carbon composites act as a light absorber to improve solar absorption (96.0%), while the vertical through-hole structure allows for fast thermal energy transportation from surface to the whole. As a result, LMXA-MA exhibits outstanding thermal energy storage (192.4 J·g-1) and high photothermal conversion efficiency (93.5%). Meanwhile, benefiting from the intrinsic low emissivity of MXene material, thermal radiation loss can be effectively suppressed by simply flipping LMXA-MA, enabling a long-term temperature control ability (605 s·g-1). The excellent heat storage property and switchable dual-mode also endow it with an infrared stealth function, which maintains camouflage for more than 240 s. This work provides a prospective solution for optimizing photothermal conversion efficiency and long-term thermal energy preservation from surface engineering and structural design.

Carbon-intercalated halloysite-based aerogel efficiently encapsulating phase change materials with excellent photothermal conversion and energy storage

Latent heat storage systems based on organic phase change materials (PCMs) are considered to be an efficient solar energy utilization strategy, but leakage vulnerability and insensitivity to sunlight of PCMs limit their further application in energy storage. In this work, a new hierarchical porous aerogel was constructed with the carbon intercalated halloysite nanotubes (CHNTs) as the assembly units for PCMs encapsulation to improve the load weight, stability and sunlight absorption. The CHNTs were first successfully synthesized through intercalation and carbonization, with the aim of increasing their specific surface area and sunlight absorption.Subsequently, the CHNTs/polyvinyl alcohol (PVA) aerogels with 3D honeycomb structure were prepared by self-assembly using a freeze-drying method, which can significantly promote the encapsulation ratio of lauric acid (LA) in the pores of both aerogels and CHNTs. The CHNTs can not only improve compressive strength of the aerogels and shape stability of the composite PCMs, but also enhance light absorption ability of the composites compared to pristine HNTs. As a support material, CHNTs aerogel (CHNP) loaded more than 92 wt% PCM (LA@CHNP) and exhibited an extremely high latent heat capacity (170.9 J/g). The LA@CHNP had good structural and thermal stability in 300 cycles without visible leakage. Besides, solar energy absorption increased from 43 % to 98 %, and the solar-to-thermal energy conversion efficiency increased to 95.88 %, which could be attributed to 3D porousness and carbon nanolayers of the CHNTs. We have successfully synthesized an eco-friendly and facile composite LA@CHNP, which will contribute to the design of advanced composites with excellent solar energy storage properties, and provide a new direction for the application of carbonized materials.

Oxidized textured stainless steel surface with passivation layer as a high temperature selective solar absorber

A nanocrystalline textured stainless steel (SS) surface passivated with an AlCr oxide layer is proposed for use as a high temperature solar selective absorbers (SSAs). The textured SS surface was prepared by oxidizing in air at 800 °C for 30 min. The heating resulted in outward diffusion of the SS substrate Mn atoms, their oxidation on the surface, and formation of octahedral Mn3O4 nanocrystals, which play a role of textured surface. The passivation AlCr oxide single layer was deposited on the textured surface using reactive RF magnetron sputtering to protect the SS from further oxidation. The solar absorptivity αs and thermal emissivity ε298K of the as-deposited SSAs were 0.84 and 0.165, respectively. In order to study high temperature stability, SSAs were heat treated under air conditions at 600–900 °C for 0.1–300 h. SSAs demonstrated thermal stability at 600 °C for at least 300 h and degradation of optical properties with performance criterion PC < 0.05 at 700, 800, and 900 °C for 300 h, 30 h, and 1 h, respectively. The increase in thickness of the surface Cr2O3 layer on SS substrate was identified as the main degradation mechanism of SSA optical performance. SSAs demonstrated a high activation energy of 330 ± 30 kJ/mol. The obtained data can be used to design high temperature SSAs for concentrating solar energy systems operating under vacuum or air conditions at 500 °C.

Fe3O4/Au@SiO2 nanocomposites with recyclable and wide spectral photo-thermal conversion for a direct absorption solar collector

The Fe3O4-based photothermal materials have been widely applied for the recycling of heavy metal nanoparticles to avoid secondary pollution in the utilization of solar energy owing to excellent magnetic properties. However, the narrow absorption band of Fe3O4 or metal nanoparticles limits their capacity for solar energy harvesting. In this paper, a recyclable and wide spectral photo-thermal conversion system (Fe3O4/Au@SiO2) based on Fe3O4 nanospheres and SiO2-modified Au nanorods (NRs) is prepared. Owing to the strong coupling effect between Fe3O4 and different Au NRs, the wide and strong absorption band from 400 nm to 1100 nm is obtained. Under the influence of magnetic field, the temperature change of nanofluids (NFs) at different positions can be controlled. When the concentration is 0.0467 vol%, the solar energy absorption fraction reaches 96.50 %. Besides, the photothermal performance of Fe3O4/Au@SiO2 NFs at different flow rates is investigated and the results show that temperature rise decreases as increasing flow rate. Finally, a water evaporator device based Fe3O4/Au@SiO2 NFs is developed. The maximum water evaporation rate of 2.6 kg m−2 h−1 can be reached and the movement of evaporator on water can be operated using magnetic field, showing great photothermal conversion performance and recovery potential in practical applications.

Design and optimization of broadband near-perfect absorber based on transition metal nitrides thin-films for solar energy harvesting

Broadband metamaterial absorbers hold promise for solar energy harvesting, but their complex designs and use of expensive noble metals hinder scalability and thermal stability. Additionally, traditional design methods are time-consuming. We propose a novel approach that combines a genetic algorithm with the transfer matrix method to optimize both material composition and layer structure for large-scale, cost-effective, and thermally stable solar absorbers. This method enables the design of near-perfect absorbers with an average absorptance exceeding 90 % and over 80 % across a broad wavelength range (0.3–2.5 μm) within the key solar spectrum. By optimizing the arrangement of metal and insulator layers using nitride materials (e.g., vanadium nitride), we achieve superior performance compared to traditional metal–insulator and insulator–metal structures. This optimization utilizes resonant absorption and the inherent absorption of metal layers. Our work paves the way for efficient and scalable solar energy harvesting devices.

Three-Dimensional Double-Layer Multi-Stage Thermal Management Fabric for Solar Desalination.

Water scarcity is a serious threat to the survival and development of mankind. Interfacial solar steam generation (ISSG) can alleviate the global freshwater shortage by converting sustainable solar power into thermal energy for desalination. ISSG possesses many advantages such as high photothermal efficiency, robust durability, and environmental friendliness. However, conventional evaporators suffered from huge heat losses in the evaporation process due to the lack of efficient thermal management. Herein, hydrophilic Tencel yarn is applied to fabricate a three-dimensional double-layer fabric evaporator (DLE) with efficient multi-stage thermal management. DLE enables multiple solar absorptions, promotes cold evaporation, and optimizes thermal management. The airflow was utilized after structure engineering for enhanced energy evaporation efficiency. The evaporation rate can reach 2.86 kg·m-2·h-1 under 1 sun (1 kW·m-2), and 6.26 kg·m-2·h-1 at a wind speed of 3 m·s-1. After a long duration of outdoor operation, the average daily evaporation rate remains stable at over 8.9 kg·m-2, and the removal rate of metal ions in seawater reaches 99%. Overall, DLE with efficient and durable three-dimensional multi-stage thermal management exhibits excellent practicality for solar desalination.

Dual-functional paper-like evaporator for boosting interfacial evaporation synchronized with organic pollutant degradation

Solar-driven interfacial evaporation is a sustainable method to produce freshwater, but volatile organic compounds (VOCs) inevitable accumulate in the condensed water, causing secondary pollution. Herein, paper-like photothermal evaporators were constructed by fixing zeolitic diazoate frameworks-8 derived N-doped carbon with different morphologies on the interwoven cellulose nanofibrils (CNFs) membranes for simultaneous steam generation and organic pollutant degradation. The results showed that the evaporator incorporated porous N-doped carbon with rhombic dodecahedron (NC-RD) into CNFs membranes not only increases the roughness to achieve broad spectrum solar absorption, but also capable of ensuring continuous evaporation of water, and maintaining a sufficient water supply. The NC-RD/CNFs membranes exhibit the high evaporation rate of 1.46 kg·m−2·h−1 under one sun. Meanwhile, N-doped carbon enable photothermal-synergistic peroxymonosulfate (PMS) activation to promote the generation of abundant 1O2 and O2∙– for degradation of methylene blue, tetracycline and phenol. Furthermore, the solar-vapor conversion efficiency and the evaporation rate are stable in a simulated seawater environment with 15 wt% NaCl solution. Importantly, an outdoor NC-RD/CNFs-based device was constructed, which realizes a high evaporation rate of 0.659 kg∙m−2∙h−1 under natural light irradiation for 10 h. The present study highlights that the NC-RD/CNFs membranes successfully coupled interfacial evaporation with PMS based-advanced oxidation processes to provide a subtlety strategy to solve the problem of VOCs accumulation in the evaporation process.

Synthesis of Ti3C2Tx MXene@Carbon-Enhanced cellulose fiber composite-based photothermal absorber for sustainable water desalination

Desalination is a process that extracts salt and minerals from seawater to produce fresh water. It is critical, particularly for those who live on islands or coastal areas. Solar thermal desalination harnesses solar energy to address some of the challenges of traditional desalination methods. It uses solar power to heat seawater directly, initiating evaporation and leaving the salt behind, and further the vapor is condensed to produce fresh water. This method reduces reliance on fossil fuels, minimizing environmental impact and energy costs. This research unveils the synthesis of a solar evaporator consisting of Ti3C2Tx MXene coated over the carbon-enhanced cellulose fibers (CCF) (hereby termed the Ti3C2Tx MXene@CCF composite), which is the first-time report in the field of solar water desalination in using sustainable solar heat absorber. The Ti3C2Tx MXene@CCF composite achieves an impressive evaporation rate of 3.8 kg m−2 h−1 under 1 sun exposure. The hydrophilic Ti3C2Tx MXene coating on the porous CCF promotes rapid water evaporation. Ti3C2Tx MXene@CCF composite maximizes evaporation rates while maintaining water purity, which is in accordance with the World Health OrganizationFF (WHO) standards.

Summer snow on Arctic sea ice modulated by the Arctic Oscillation

Since the 1970s, Arctic sea ice has undergone unprecedented change, becoming thinner, less extensive and less resilient to summer melt. Snow’s high albedo greatly reduces solar absorption in sea ice and the upper ocean, which mitigates sea–ice melt and ocean warming. However, the drivers of summertime snow depth variability are unknown. The Arctic Oscillation is a mode of natural climate variability, influencing Arctic snowfall and air temperatures. Thus, it may affect summertime snow conditions on Arctic sea ice. Here we examine the role of the Arctic Oscillation in summer snow depth variability on Arctic sea ice in 1980–2020 using atmospheric reanalysis, snow modelling and satellite data. The positive phase leads to greater snow accumulation, ranging up to ~4.5 cm near the North Pole, and higher surface albedo in summer. There are more intense, frequent Arctic cyclones, cooler temperatures aloft and greater snowfall relative to negative and neutral phases; these conditions facilitate a more persistent summer snow cover, which may lessen sea-ice melt and ocean warming. The Arctic Oscillation influence on summertime snow weakens after 2007, which suggests that future warming and Arctic sea-ice loss might modify the relationship between the Arctic Oscillation and snow on Arctic sea ice.