Photothermal Conversion Performance Research Articles

Polyethylene glycol/melamine foam composite phase change materials modified by CdS/Ag exhibits high photothermal conversion performance

CdS has been shown to be an excellent photon trap with strong absorption of light at visible and near-infrared wavelengths. The use of CdS for phase change material (PCM) modification can significantly improve its photothermal conversion performance. However, due to the unique energy band structure of CdS, the difficulty in electron conduction leads to poor thermal conductivity. This problem can be improved by introducing high thermal conductivity nanometals for modification, however, the effective combination of CdS and nanometals has been challenging. In this study, a new preparation strategy is demonstrated, in which Ag nanoparticles (NPs) with similar lattice parameters and crystalline coordination to CdS is first introduced on the surface of carbonized melamine foam (CMF), followed by the introduction of CdS NPs. This similar structure helps to form a better interfacial bond between CdS and Ag. The resulting stabilized structure enables the composite phase change material (CPCM) to achieve 96.1 % PEG loading with an ultra-high photothermal conversion efficiency of 94.6 %, thermal conductivity of 0.61 W/m∙K, and excellent antimicrobial activity. This study provides valuable guidance for the engineering design of CPCM with high photothermal conversion performance and suggests its practical application value in seawater evaporation and thermal management of medical devices.

Triply Interlocked [2]catenanes: Rational Synthesis, Reversible Conversion Studies and Unprecedented Application in Photothermal Responsive Elastomer

Triply interlocked [2]catenane complexes featuring two identical, mechanically interlocked units are extraordinarily rare chemical compounds, whose properties and applications remain open to detailed studies. Herein, we introduce the rational design of a new ligand precursor, L1, suitable for the synthesis of six triply interlocked [2]catenanes by coordination‐driven self‐assembly. The interlocked compounds can be reversibly converted into the corresponding simple triangular prism metallacage by addition of H2O or DMF solvents to their CH3OH solutions, thereby demonstrating the importance of π···π stacking and hydrogen bonding interactions in the formation of triply interlocked [2]catenanes. Moreover, extensive studies have been conducted to assess the remarkable photothermal conversion performance. Complex 6a, exhibiting outstanding photothermal conversion performance (conversion efficiency in solution : 31.82%), is used to prepare novel photoresponsive elastomer in combination with thermally activated liquid crystal elastomer. The resultant material displays robust response to near‐infrared (NIR) laser and the capability of completely reforming the shape and reversible actuation, paving the way for the application of half‐sandwich organometallic units in photo‐responsive smart materials.

Triply Interlocked [2]catenanes: Rational Synthesis, Reversible Conversion Studies and Unprecedented Application in Photothermal Responsive Elastomer.

Triply interlocked [2]catenane complexes featuring two identical, mechanically interlocked units are extraordinarily rare chemical compounds, whose properties and applications remain open to detailed studies. Herein, we introduce the rational design of a new ligand precursor, L1, suitable for the synthesis of six triply interlocked [2]catenanes by coordination-driven self-assembly. The interlocked compounds can be reversibly converted into the corresponding simple triangular prism metallacage by addition of H2O or DMF solvents to their CH3OHsolutions, thereby demonstrating the importance of π···πstacking and hydrogen bonding interactions in the formation of triply interlocked [2]catenanes. Moreover, extensive studies have been conducted to assess the remarkable photothermal conversion performance. Complex 6a, exhibiting outstanding photothermal conversion performance (conversion efficiency in solution : 31.82%), is used to prepare novel photoresponsive elastomer in combination with thermally activated liquid crystal elastomer. The resultant material displays robust response to near-infrared(NIR)laser and the capability of completely reforming the shape and reversible actuation, paving the way for the application of half-sandwich organometallic units in photo-responsive smart materials.

Preparation and performance enhancement of MXene/Na2HPO4·12H2O@SiO2 phase change microcapsule

Currently, the leakage problem of phase change materials can be solved by the microencapsulation technology. Inorganic hydrated salt materials have the advantages of high latent heat density, high thermal conductivity and low cost. How to construct inorganic hydrated salt microcapsules with excellent heat storage capacity and photothermal conversion performance maintains a challenge. In this work, the MXene/Na2HPO4·12H2O@SiO2 (MXene/MPCMs) composite phase change microcapsules were designed and prepared. The Na2HPO4·12H2O was directly used as phase change material and TEOS was used as raw material to generate SiO2 wall material. The MXene played a key and important role in simultaneously enhancing their photothermal conversion efficiency while maintaining available latent heat. The prepared composite microcapsules (MPCM-1) showed more obvious heat storage and release characteristics, and the latent heat reached 169.62 J/g. Besides, when the hydrated salt was encapsulated in silica shell, the supercooling degree of hydrated salt was reduced from 14.2 °C to 10.1 °C. With the increase of MXene content, the maximum surface temperature of microcapsules significantly increased. Based on the results of surface temperature distribution, the photothermal conversion ability and heat transfer rate of microcapsules were effectively improved, which was mainly attributed to the remarkable light absorption conversion ability of MXene. When the MXene was added, the MXene/MPCMs still showed excellent heat storage properties (~ 156.64 J/g). At the same time, the MXene/MPCMs showed good chemical compatibility, crystallization characteristics and thermal stability. Considering available performance enhancement, the prepared microcapsules show good application prospect in solar energy utilization.

Coordination assembly and NIR photothermal conversion of Metal-organic framework based on 5-(2-cyanophenoxy) isophthalic acid

The development of new photothermal conversion materials in the field of metal-organic frameworks (MOFs) shows broad prospects, but their design synthesis and proper mechanism analysis are still full of huge challenge. Here, four novel MOFs were constructed with 5-(2-cyanophenoxy) isophthalic acid, {Ni(2-CB-IPA)(bpp)(H2O)}n (1), {Ni2(2-CB-IPA)2(bpa)2(H2O)2}n (2), {Co(2-CB-IPA)(bpp)}n (3), {Mn2(2-CB-IPA)2 (bpp)(H2O)2}n (4). (Where 2-CB-IPA = 5-(2-cyanophenoxy) isophthalic acid, bpa = 1,2-bis(4-pyridine)-ethane; and bpp = 1,3-bis(4-pyridyl)propane). The absorption peak at 730 nm in the near-infrared region indicates that different charge transfer interactions affect the photothermal conversion ability. Under laser irradiation (730 nm, 0.45 W cm−2), such compounds exhibit different and distinct warming processes (1 from 20.8 to 91.8 °C; 2 from 20.1 °C to 86.2 °C; 3 from 20.6 to 77.1 °C) except for compound 4. The excellent crystallinity of these materials after irradiation demonstrates excellent thermal stability and cycling durability. Subsequently, further research on the structure-activity relationship revealed that strong π - π interactions are also the reason for the excellent performance of NIR photothermal conversion of 1 under the premise of high NIR absorption. This work provides a visual platform for the photothermal phenomena of crystalline materials.

Injectable Photothermal PDA/Chitosan/β-Glycerophosphate Thermosensitive Hydrogels for Antibacterial and Wound Healing Promotion.

Controlling infections while reducing the use of antibiotics is what doctors as well as researchers are looking for. As innovative smart materials, photothermal materials can achieve localized heating under light excitation for broad-spectrum bacterial inhibition. A polydopamine/chitosan/β-glycerophosphate (PDA/CS/β-GP) temperature-sensitive hydrogel with excellent antibacterial ability was synthesized in the study. Initially, the hydrogel has good biocompatibility. In vitro experiments reveal its non-cytotoxic property when co-cultured with gingival fibroblasts and non-hemolytic capability. Concurrently, the in vivo biocompatibility is confirmed through liver and kidney blood markers and staining of key organs. Crucially, the hydrogel has excellent photothermal conversion performance, which can realize the photothermal conversion of hydrogel up to 3mm thickness. When excited by near-infrared light, localized heating is attainable, resulting in clear inhibition impacts on both Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), with the inhibition rates of 91.22% and 96.69%, respectively. During studies on mice's infected wounds, it is observed that the hydrogel can decrease S. aureus' presence in the affected area when exposed to near-infrared light, and also lessen initial inflammation and apoptosis, hastening tissue healing. These findings provide valuable insights into the design of antibiotic-free novel biomaterials with good potential for clinical applications. This article is protected by copyright. All rights reserved.

Polysaccharide-Based Micro/Nanomotors for Active Ingredient Delivery in Food.

Micro/nanomotors (MNMs) are miniature devices that can generate energy through chemical reactions or physical processes, utilizing this energy for movement. By virtue of their small size, self-propulsion, precise positioning within a small range, and ability to access microenvironments, MNMs have been applied in various fields including sensing, biomedical applications, and pollutant adsorption. However, the development of food-grade MNMs and their application in food delivery systems have been scarcely reported. Currently, there are various issues with the decomposition, oxidation, or inability to maintain the activity of some nutrients or bioactive substances, such as the limited application of curcumin (Cur) in food. Compared to traditional delivery systems, MNMs can adjust the transport speed and direction as needed, effectively protecting bioactive substances during delivery and achieving efficient transportation. Therefore, this study utilizes polysaccharides as the substrate, employing a simple, rapid, and pollution-free template method to prepare polysaccharide-based microtubes (PMTs) and polysaccharide-based micro/nanomotors (PMNMs). PMNMs can achieve multifunctional propulsion by modifying ferrosoferric oxide (Fe3O4), platinum (Pt), and glucose oxidase (GOx). Fe-PMNMs and Pt-PMNMs exhibit excellent photothermal conversion performance, showing promise for applications in photothermal therapy. Moreover, PMNMs can effectively deliver curcumin, achieving the effective delivery of nutrients and exerting the anti-inflammatory performance of the system.

Cotton Fabric-Reinforced Hydrogels with Excellent Mechanical and Broad-Spectrum Photothermal Antibacterial Properties.

Antibacterial hydrogel wound dressings hold great potential in eliminating bacteria and accelerating the healing process. However, it remains a challenge to fabricate hydrogel wound dressings that simultaneously exhibit excellent mechanical and photothermal antibacterial properties. Here we report the development of polydopamine-functionalized graphene oxide (rGO@PDA)/calcium alginate (CA)/Polypyrrole (PPy) cotton fabric-reinforced hydrogels (abbreviated as rGO@PDA/CA/PPy FHs) for tackling bacterial infections. The mechanical properties of hydrogels were greatly enhanced by cotton fabric reinforcement and an interpenetrating structure, while excellent broad-spectrum photothermal antibacterial properties based on the photothermal effect were obtained by incorporating PPy and rGO@PDA. Results indicated that rGO@PDA/CA/PPy FHs exhibited superior tensile strength in both the warp (289 ± 62.1 N) and weft directions (142 ± 23.0 N), similarly to cotton fabric. By incorporating PPy and rGO@PDA, the swelling ratio was significantly decreased from 673.5% to 236.6%, while photothermal conversion performance was significantly enhanced with a temperature elevated to 45.0 °C. Due to the synergistic photothermal properties of rGO@PDA and PPy, rGO@PDA/CA/PPy FHs exhibited excellent bacteria-eliminating efficiency for S. aureus (0.57%) and E. coli (3.58%) after exposure to NIR for 20 min. We believe that the design of fabric-reinforced hydrogels could serve as a guideline for developing hydrogel wound dressings with improved mechanical properties and broad-spectrum photothermal antibacterial properties for infected-wound treatment.

Synthesis of Structure-Adjustable R-Au/Pt-CdS Nanohybrids with Strong Plasmon Coupling and Improved Photothermal Conversion Performance.

Noble metal nanomaterials with a localized surface plasmon resonance effect exhibit outstanding advantages in areas such as photothermal therapy and photocatalysis. As a unique plasmonic metal nanostructure, gold nanobipyramids have been attracting much interest due to their strong specific local electric field intensity, large optical cross sections, and high refractive index sensitivity. In this study, we propose a novel three-component hetero-nanostructure composed of rough gold nanobipyramids (R-Au NBPs), Pt, and CdS. Initially, purified gold nanobipyramids are regrown to form R-Au NBPs that have a certain degree of roughness. These R-Au NBP substrates with a rough surface provide more hotspots and strengthen the intensity of localized electric fields. Subsequently, Pt and CdS nanoparticles are selectively deposited onto the surface of R-Au NBPs. Pt nanoparticles can provide more active sites. Each component of this hetero-nanostructure directly contacts others, creating multiple electron transfer channels. This novel design allows for tunable localized plasmon resonance wavelengths ranging from the visible to near-infrared regions. These factors contribute to the final superior photothermal conversion performance of the R-Au/Pt-CdS nanohybrids. Under the irradiation of near-infrared light (1064 nm), the photothermal conversion efficiency of R-Au/Pt-CdS reached 38.88%, which is 4.49, 1.5, and 1.22 times higher than that of Au NBPs, R-Au NBPs, and R-Au NBPs/Pt, respectively.

Self-floating and long-term stable Ti3C2TX/polyurethane composite membranes with highly efficient photothermal conversion performances for multiple applications

Photothermal conversion has emerged as a highly effective method for converting solar energy into thermal energy for a variety of applications. In this study, we developed Ti3C2TX/PU membranes with exceptional photothermal conversion performance using a simple casting process. The Ti3C2TX/PU membranes are flexible, self-floating, and possess suitable strength and hydrophilicity. Additionally, they exhibit enhanced sunlight absorption capability and excellent thermal stability. When these membranes were applied for solar-driven seawater evaporation, they achieved an evaporation rate of 1.35 kg∙m−2 h−1 and a conversion efficiency of 84.85 % under 1 sun. In real outdoor conditions, they also displayed satisfactory evaporation performance. Impressively, the Ti3C2TX/PU membranes exhibited stable salt resistance and remarkable self-desalting properties, which are crucial for practical seawater evaporation applications. Furthermore, we observed that the photothermal performance of the Ti3C2TX/PU membranes improved with a higher Ti3C2TX content. Particularly noteworthy is the significant reduction in ice melting time when these membranes are wrapped around power wires, demonstrating their excellent photothermal deicing capabilities. The Ti3C2TX/PU membranes also showed promising application potential in low-temperature photothermal therapy treatment. We believe that such efficient and stable photothermal membranes will provide a sustainable solution for addressing challenges related to human health, life, and survival.

Glutathione-mediated copper sulfide nanoplatforms with morphological and vacancy-dependent photothermal catalytic activity for multi-model tannic acid assays

Interface engineering and vacancy engineering play an important role in the surface and electronic structure of nanomaterials. The combination of the two provides a feasible way for the development of efficient photocatalytic materials. Here, we use glutathione (GSH) as a coordination molecule to design a series of CuxS nanomaterials (CuxS-GSH) rich in sulfur vacancies using a simple ultrasonic-assisted method. Interface engineering can induce amorphous structure in the crystal while controlling the formation of porous surfaces of nanomaterials, and the formation of a large number of random orientation bonds further increases the concentration of sulfur vacancies in the crystal structure. This study shows that interface engineering and vacancy engineering can enhance the light absorption ability of CuxS-GSH nanomaterials from the visible to the near-infrared region, improve the efficiency of charge transfer between CuxS groups, and promote the separation and transfer of optoelectronic electron-hole pairs. In addition, a higher specific surface area can produce a large number of active sites, and the synergistic and efficient photothermal conversion efficiency (58.01%) can jointly promote the better photocatalytic performance of CuxS-GSH nanomaterials. Based on the excellent hot carrier generation and photothermal conversion performance of CuxS-GSH under illumination, it exhibits an excellent ability to mediate the production of reactive oxygen species (ROS) through peroxide cleavage and has excellent peroxidase activity. Therefore, CuxS-GSH has been successfully developed as a nanoenzyme platform for detecting tannic acid (TA) content in tea, and convenient and rapid detection of tannic acid is achieved through the construction of a multi-model strategy. This work not only provides a new way to enhance the enzyme-like activity of nanomaterials but also provides a new prospect for the application of interface engineering and vacancy engineering in the field of photochemistry.

Stability, Thermophysical, Optical and Photothermal Properties of ZnO Nanofluids with Added Anionic/Cationic Mixed Surfactants

Metal oxide nanofluid is a new type of heat transfer medium with good thermal performance, which can be used to improve the heat collection and photothermal conversion performance of the collector. The development of new nanofluids with excellent stability, thermophysical and photothermal properties is very important for solar thermal utilization. In this paper, the ZnO nanofluids with SDS/CTAB mixed surfactants were prepared by two-step method. Their stability, thermophysical, optical and photothermal properties were studied based on experimental data. Then, the optimum concentration and preparation conditions of the proposed ZnO nanofluids adding SDS/CTAB with good photothermal performance were obtained. The results showed that the ZnO nanofluids with the addition of SDS/CTAB hybrid surfactant has good dispersion stability and its thermal conductivity can reach 0.772 W/(m·K). The transmittance was as low as 19.0.10% and the extinction coefficient was as high as 7.25 cm−1. In addition, the addition of the SDS/CTAB hybrid surfactant caused the ZnO nanofluids to exhibit better photothermal conversion efficiency up to 87%, which was superior to that of the control group with the addition of other surfactants. Therefore, ZnO nanofluids with the addition of SDS/CTAB have great potential as DASC working fluids.

A novel hierarchical chromium black membrane prepared by electroplating for desalination

Solar-driven interfacial evaporation (SDIE), a technology for local solar energy conversion through photothermal materials, has been greatly developed. The metal oxide semiconductors have excellent photothermal conversion performance and are considered the most promising materials for photothermal conversion. Hierarchical structure with large surface area is beneficial to improve the photothermal conversion efficiency through the light-trapping effect and reduces the evaporation enthalpy of water. Herein, chromium black (Cr, Cr2O3, CrO3-x) photothermal membranes (CBPM) with ganoderma-like hierarchical structure were prepared by electrochemical oxidation. Due to the small interlayer spacing of the ganoderma-like structure, the light absorption of CBPM (M7) can reach 78.53 %, which in turn promotes the conversion of solar energy due to the low thermal conductivity of the chromium black layer, resulting in a high evaporation rate of 1.64 kg m−2 h−1. The solar-to-vapor conversion efficiency is up to 90.39 % under 1 sun irradiation. Meanwhile, the superhydrophilicity of the membrane is conducive to salt redissolution at night, so there was not much performance degradation after 24 cycles. This study provides a new solution for water treatment using chromium black as a photothermal material with great potential for solar production of fresh water.

Enhancing fire safety, electromagnetic interference shielding, and photothermal conversion performances of wearable polyamide fabrics through eco-friendly coatings

The demand for smart textiles in wearable technology has significantly increased in the last decade. However, the inherent flammability of most textiles poses a big challenge, especially when exposed to elevated surface temperatures induced by electrical or optical stimuli, increasing the risk of fire. The process of synthesizing flame retardants involves the use of organic solvents, which is not in line with the requirements of sustainable development. This research focuses on establishing an eco-friendly and stable coating for polyamide 6 (PA6) fabric through a solvent-free synthesis and innovative alternating deposition method. It has been demonstrated that the treated PA6 fabric exhibits rapid self-extinguishing properties, eliminating melt dripping and achieving a remarkable limiting oxygen index of 25.5%. Furthermore, the peak heat release rate and total heat release rate of the treated PA6 fabric decrease by 32.9% and 22.7%, respectively, compared to that of the control PA6. Under simulated sunlight exposure at an intensity of 150 mW·cm−2, the treated PA6 fabric rapidly reaches a surface temperature of 78.6 °C within 300 s. Additionally, the treated PA6 fabric demonstrates an electromagnetic interference (EMI) shielding efficiency of 24.0 dB in the X-band, highlighting the efficacy of the innovative coating. This result is attributed to the conductive network formed by the alternating deposition of MXene and polyphosphamide. This work not only improves the fire safety in wearable textiles but also presents a promising and green strategy for developing multifunctional wearable textiles with enhanced safety features.

Synthesis of Prussian blue analogue nanoboxes with enhanced photothermal and catalytic performance

Recently, Prussian blue analogues (PBA) were widely studied in energy and electrochemistry field. However, the strategy of preparation for PBA nanoboxes with enhanced photothermal conversion effect is rarely discussed due to the lower absorption in near infrared region (NIR) of PBAs. Herein, a novel CuMnFe nanobox was prepared for the first time by a simple S etching method. After S etching, the as-prepared CuMnFe nanobox possessed outstanding photothermal conversion performance and amazing catalytic activity due to introduction of S element. Various optimization experiments were also performed to investigate the preparation of CuMnFe nanobox. The mechanism of the enhanced performance was also discussed. This work will pave a way to enhance the performance of PBAs and expand their application from traditional energy chemistry to the field of biomedicine.

Construction of Bi2O3−x/NiAl-LDH S-scheme heterojunction for boosting photothermal-assisted photocatalytic CO2 reduction

In this study, a new type of 2D/2D Bi2O3−x/NiAl-LDH (BO/NA-LDH) S-scheme photocatalyst was prepared by combining NiAl-LDH with Bi2O3−x by wet chemical deposition for obtaining efficient photothermal-assisted photocatalytic reduction of CO2 under simulated sunlight irradiation. In particular, the as-prepared optimal 50-BO/NA-LDH sample exhibited the CO production yield of 83.55 ± 2.76 μmol/g/h, which was 9 and 27 times that of BO (9.32 ± 0.62 μmol/g/h) and NA-LDH (3.09 ± 0.38 μmol/g/h), respectively. The enhancement of photothermal-assisted activity over the 50-BO/NA-LDH system was mainly attributed to the coupling of the photothermal conversion performance of Bi2O3−x and improving the migration efficiency of interface carriers of S-scheme heterojunction and 2D/2D structure. This study presents a promising strategy for the development of high-efficient photothermal-assisted photocatalysts.

Remote-controlled saline tolerant tough-yet-strong solar vapor evaporator based on multifunctional Fe3O4 nanoparticles reinforced gel-nacre

Solar vapor evaporators in saline hold enormous potentials in resource sustainability, seawater desalination, as well as renewable energy harvesting. Nanocomposite hydrogels with the property of photothermal conversion have emerged as candidates for solar-driven steam generation devices, but are limited by remote control and low mechanical properties in a saline environment. Here, we developed a remote-controlled, saline tolerant, and tough-yet-strong solar vapor evaporator based on multifunctional Fe3O4 nanoparticles reinforced gel-nacre. The Fe3O4 nanoparticles play triple roles of acting as nano-crosslinks, photothermal converters, and untethered manipulation, coupling gel-nacre matrix with a shrinking tendency in saline that contributes to synergistic mechanical reinforcement. Such integrated magnetic nanocomposite hydrogel exhibits tough-yet-strong mechanical properties (19.58 MPa ultimate strength, 300 % failure strain, self-recoverability under 500 %, and fatigue-resistance), addressing the challenges of remote operation system and high strength requirement for practical applications. Moreover, good photothermal conversion performances (1.26 kg m−2 h−1 evaporation rate and 92.84 % evaporation efficiency) could be achieved with remotely controlled motion or adjustable position simultaneously under an external magnetic field. The intelligent solar vapor evaporation system based on multifunctional magnetic Fe3O4@gel-nacre nanocomposite provides new opportunities for flexible energy-transducing devices with untethered manipulation in saline environment.

Novel MoS2/montmorillonite hybrid aerogel encapsulated PEG as composite phase change materials with superior solar-thermal energy harvesting and storage

Phase change materials (PCMs) offer significant advantages in energy conversion and storage by facilitating the storage and release of thermal energy during phase transition processes. However, challenges such as leakage during PCM phase transitions and poor light absorption properties have constrained their application in the field of photothermal energy storage. In this study, Montmorillonite (Mt) and molybdenum disulfide (MoS2) has been used to design and synthesize hybrid aerogels (MoS2/Mt) boasting high mechanical strength and excellent photothermal conversion performance. These aerogels are then used to encapsulate polyethylene glycol (PEG) to prepare composite PCMs with outstanding solar-thermal conversion and storage performances. The results show that the synthesized MoS2/Mt-PEG composite PCMs exhibit high enthalpies of melting and solidification of 169.16 J/g and 170.78 J/g, respectively, while the aerogel supporting material has a high compressive modulus of 1.96 MPa. Moreover, the composite material displayed excellent thermal stability and leakage resistance after undergoing 30 melting-cooling cycles. Furthermore, the incorporation of MoS2 imparted outstanding light absorption properties to the MoS2/Mt-PEG composite, resulting in a high light absorption and photothermal conversion-storage efficiency of 93.4 % and 96.47 %, respectively. Synthesized composite PCMs also demonstrate outstanding performance in solar-thermal-electricity conversion, achieving a voltage output of 458 mV under illumination conditions and maintaining a sustainable voltage output even after removing the light source. Thus, the composite PCMs prepared in this work can meet the requirements of high enthalpy, effective leakage prevention, efficient solar-thermal conversion and solar-thermal-electricity conversion performance, thereby presenting potential applications in practical solar energy collection, conversion, and storage.

Solid waste reutilization of FCC petroleum coke for solar evaporation as a photothermal conversion material

Petroleum coke is a common industrial waste and is generally considered to be an amorphous carbonaceous or highly aromatized polymer carbide. In this study, petroleum coke was used as the main raw material and loaded on a nonwoven fabric to construct an interfacial solar evaporator with a micro-nano structure. The light absorption, evaporation rate and photothermal efficiency of CB@EM with different loading concentrations were investigated with different light intensities, coming in to evaluate the photothermal conversion performance of CB@EM. The results showed that the petroleum coke was resistant to acid and alkali. The simply prepared CB@EM has excellent photothermal conversion performance, and the evaporation rates of 50-CB@EM were 1.37, 2.34, and 5.61 kg m−2 h−1 at 0.5 sun, 1 sun, and 1.5 sun, respectively; meanwhile, the average evaporation rate of 50-CB@EM after 60 h of continuous evaporation at 1 sun, which realized efficient and continuous water evaporation was 2.39 kg m−2 h−1, the evaporation efficiency was 93.29 %, and the salt would preferentially accumulate from both ends of 50-CB@EM. In addition, CB@EM has flame retardancy, which can reduce the risk of fire during transportation. This study provides a method to treat petroleum coke industrial waste residue using clean energy and apply it in solar photo-thermal water evaporation, which has great potential for industrial application.

Polyethersulfone-silica aerogel/ polypyrrole solar evaporation membrane for wastewater treatment and desalination

Solar interfacial evaporation utilizes a specific structure of the evaporator to confine the energy to the light absorbing layer, so that the water completes efficient evaporation on the surface of the structure. In this paper, polyethersulfone- silica aerogel/ polypyrrole solar evaporation membranes (PES-SiO2/PPy) with excellent photo-thermal conversion and efficient seawater desalination performance were prepared by loading PPy on polyethersulfone-silica aerogel ultrafiltration membranes (PES-SiO2) via in situ polymerization. With its stable and efficient thermal insulation performance and heat absorption ability, the temperature on the surface of the evaporation membrane was as high as 49.9 °C under 1 kW m−2 light intensity, and the maximum evaporation rate reached 1.86 kg m−2 h−1, with an evaporation efficiency of 97%. The evaporation membranes also have long-term stable evaporation performance. At an outdoor light intensity of 0.8 kW m−2, the evaporation rate of simulated seawater reached 1.87 kg m−2 h−1 with a high evaporation efficiency of 131.6%, which can be realized for highly efficient desalination and dye-containing wastewater treatment with the aid of ambient energy. The present work demonstrates the efficient solar evaporation performance of ultra-low-cost evaporation membranes with the prospect of large-scale water purification treatment.