Photothermal Properties Research Articles

Aeration-Free Photo-Fenton-Like Reaction Mediated by Heterojunction Photocatalyst toward Efficient Degradation of Organic Pollutants.

The regulation of peroxymonosulfate (PMS) activation by photo-assisted heterogeneous catalysis is under in-depth investigation with potential as a replaceable advanced oxidation process in water purification, yet it remains a significant challenge. Herein, we demonstrate a strategy to construct polyethylene glycol (PEG) well-coupled dual-defect VO-M-Co3O4@CNx S-scheme heterojunction to degrade organic pollutants without aeration, which dramatically provides abundant active sites, excellent photo-thermal property, and distinct charge transport pathway for PMS activation. The degradation rate of VO-M-Co3O4@CNx in anaerobic conditions shows a higher efficient rate (4.58 min-1 g-2) than in aerobic conditions (1.67 min-1 g-2). Experimental evidence reveals that VO-M-Co3O4@CNx promotes more rapid redox conversion of photoexcited electrons induced by defects with PMS under anaerobic conditions compared to aerobic conditions. Additionally, in situ experiments and DFT provide mechanistic insights into the regulation pathway of PMS activation via synergistic defect-induced electron, revealing the competitive effect between O2 and PMS over VO-M-Co3O4@CNx during the reaction process. The continuous flow reactor and flow cytometry results demonstrated that the VO-M-Co3O4@CNx/PMS/Vis system has remarkably enhanced stability and purification capability for removing organic pollutants. This work provides valuable insights into regulating the heterologous catalysis oxidation process without aeration through the photoexcitation synergistic PMS activation.

Synergistic Phototherapy Using Zwitterionic Crystalline Nanoaggregates of Orthogonal Donor–Acceptor Small‐Molecule Dyads

AbstractDeveloping nanophotosensitizer (nanoPS) for synergistic phototherapy by leveraging the aggregation of small‐molecule dyes is compelling frontier in precision medicine, but challenges remain due to the limited understanding of the interactions between molecular structure, assembly behavior, and theranostic function. Here, the concept of “spin‐orbit charge‐transfer intersystem crossing (SOCT‐ISC) in crystalline aggregates” is introduced, which significantly enhances photodynamic (PD) and photothermal (PT) properties of small‐molecule‐based nanoPS. Specifically, a cationic pyridine (Py) group is incorporated at the meso‐position of a tricyanofuran (TCF)‐containing anionic heptamethine cyanine (TCF‐Cy7‐TCF) dye to construct an orthogonal charge‐transfer dyad (TCF‐Cy7(Py)‐TCF), boosting triplet state formation through SOCT‐ISC mechanism to enhance the PD properties. Remarkably, the zwitterion moieties impart TCF‐Cy7(Py)‐TCF with high crystallinity even at ultralow concentrations, dictating its stacking behavior within aggregates and enhancing both PT and PD properties. The TCF‐Cy7(Py)‐TCF nanoaggregates exhibit superior singlet oxygen quantum yield (0.8% vs 0.2%) and photothermal conversion efficiency (55.06% vs 7.78%) compared to TCF‐Cy7‐TCF. Impressively, TCF‐Cy7(Py)‐TCF preferentially accumulates at tumor sites, yielding high signal‐to‐background ratios for tumor imaging in NIR‐I and NIR‐II windows, with minimal nonspecific binding. Finally, in vivo experiments confirm TCF‐Cy7(Py)‐TCF nanoaggregates function as nanoPS for synergistic phototherapy, offering a simple yet effective strategy to design single‐component PS for clinical translation.

Alternating Donor-Acceptor Ladder-Type Heteroarene for Efficient Photothermal Conversion via Boosting Non-Radiative Decay.

The development of novel ladder-type conjugated molecules is crucial for advancing supramolecular chemistry and material science. In this study, we report a straightforward synthesis of new alternating donor-acceptor (D-A) ladder-type heteroarene, FCDTDPP, and demonstrate its application as photothermal agent for imaging and cancer therapy. FCDTDPP is constructed by vinylene bridge between cyclopentadithiophene (D) and diketopyrrolopyrrole (A) through intramolecular Friedel-Crafts type reaction. FCDTDPP exhibits unique combination of good molecular planarity, efficient intra/inter-molecular mixed D-A interactions, and local aromaticity. These features collectively contribute to its broad and intense absorptions with narrow bandgap in red band of the spectra, coupled with multiple vibrational absorption feature, thereby enhancing non-radiative decay process and resulting in efficient photothermal conversion property. FCDTDPP and its nanoparticles (NPs) exhibit superior photothermal conversion performance and stability under 660 nm laser irradiation. Moreover, in vitro studies reveal that FCDTDPP NPs possess excellent biocompatibility, low cytotoxicity, and robust photothermal therapeutic efficacy, a finding further corroborated by preliminary in vivo experiments in tumor-bearing mice. This work charts a novel course for the molecular engineering of organic photothermal conversion systems, propelling relevant research forward.

Alternating Donor‐Acceptor Ladder‐Type Heteroarene for Efficient Photothermal Conversion via Boosting Non‐Radiative Decay

The development of novel ladder‐type conjugated molecules is crucial for advancing supramolecular chemistry and material science. In this study, we report a straightforward synthesis of new alternating donor‐acceptor (D‐A) ladder‐type heteroarene, FCDTDPP, and demonstrate its application as photothermal agent for imaging and cancer therapy. FCDTDPP is constructed by vinylene bridge between cyclopentadithiophene (D) and diketopyrrolopyrrole (A) through intramolecular Friedel‐Crafts type reaction. FCDTDPP exhibits unique combination of good molecular planarity, efficient intra/inter‐molecular mixed D‐A interactions, and local aromaticity. These features collectively contribute to its broad and intense absorptions with narrow bandgap in red band of the spectra, coupled with multiple vibrational absorption feature, thereby enhancing non‐radiative decay process and resulting in efficient photothermal conversion property. FCDTDPP and its nanoparticles (NPs) exhibit superior photothermal conversion performance and stability under 660 nm laser irradiation. Moreover, in vitro studies reveal that FCDTDPP NPs possess excellent biocompatibility, low cytotoxicity, and robust photothermal therapeutic efficacy, a finding further corroborated by preliminary in vivo experiments in tumor‐bearing mice. This work charts a novel course for the molecular engineering of organic photothermal conversion systems, propelling relevant research forward.

Side Chain Phenyl Isomerization-Induced Spatial Conjugation for Achieving Efficient NIR-II Phototheranostic Agents.

The contradiction of near-infrared II (NIR-II) emission and photothermal effects limits the development of phototheranostic agents (PTAs) in many emerging cutting-edge applications. Organic aggregates present a promising opportunity for the balance of competitive relaxation processes through the manipulation of molecular structure and packing. Herein, side chain phenyl isomerization-induced spatial conjugation was proposed for constructing A-D-A type NIR-II PTAs with simultaneous enhancement of fluorescence brightness and photothermal properties. Three pairs of mutually isomeric fluorophores, whose phenyls respectively located at the outside (o-series) and inside (i-series) of the side chain, were designed and synthesized. The positional isomerization of the phenyl endows the o-series crystals with strong spatial conjugation between the phenyl group on the side chain and the backbone, as well as interlocked planar network, which is different to that observed in the i-series. Thus, all o-series nanoparticles (NPs) exhibit red-shifted absorption, enhanced NIR-II emission, and superior photothermal properties than their i-series counterparts. A prominent member of the o-series, o-ITNP NPs, demonstrated efficacy in facilitating NIR-II angiography, tumor localization, and NIR-II imaging-guided tumor photothermal therapy. The success of this side chain phenyl isomerization strategy paves the way for precise control of the aggregation behavior and for further development of efficient NIR-II PTAs.

Side Chain Phenyl Isomerization‐Induced Spatial Conjugation for Achieving Efficient NIR‐II Phototheranostic Agents

The contradiction of near‐infrared II (NIR‐II) emission and photothermal effects limits the development of phototheranostic agents (PTAs) in many emerging cutting‐edge applications. Organic aggregates present a promising opportunity for the balance of competitive relaxation processes through the manipulation of molecular structure and packing. Herein, side chain phenyl isomerization‐induced spatial conjugation was proposed for constructing A‐D‐A type NIR‐II PTAs with simultaneous enhancement of fluorescence brightness and photothermal properties. Three pairs of mutually isomeric fluorophores, whose phenyls respectively located at the outside (o‐series) and inside (i‐series) of the side chain, were designed and synthesized. The positional isomerization of the phenyl endows the o‐series crystals with strong spatial conjugation between the phenyl group on the side chain and the backbone, as well as interlocked planar network, which is different to that observed in the i‐series. Thus, all o‐series nanoparticles (NPs) exhibit red‐shifted absorption, enhanced NIR‐II emission, and superior photothermal properties than their i‐series counterparts. A prominent member of the o‐series, o‐ITNP NPs, demonstrated efficacy in facilitating NIR‐II angiography, tumor localization, and NIR‐II imaging‐guided tumor photothermal therapy. The success of this side chain phenyl isomerization strategy paves the way for precise control of the aggregation behavior and for further development of efficient NIR‐II PTAs.

High‐Performance Infrared Scene Generation Using a Double‐S Microbridge Photothermal Film Emitter With Ultralarge Array

AbstractInfrared emitters are highly desirable for applications in infrared imaging and stealth technology. Photothermal film emitters, which are driven by light, have garnered considerable interest due to their excellent photothermal properties and ease of fabrication. However, existing photothermal films often suffer from low photothermal conversion efficiency (PCE) and limited array scale. Here, a photothermal film emitter featuring a double‐S microbridge structure is presented, which comprehensively considering the PCE and frame rate. Initially, Si microbridges are fabricated within each microstructure to support the photothermal film. The pattern structure is then arranged into a double‐S configuration to manipulate the thermal conductivity. By optimizing the length and width of the double‐S pattern, high PCE and fast frame rates are achieved. The double‐S microbridge structure photothermal film emitter is fabricated with a 4‐inch diameter, forming an ultra‐large array with over 3000 × 3000 pixels. The absorption and photothermal conversion characteristics are studied, revealing a maximum temperature of 582.70 K and a highest PCE of 16.32%. Time‐dependent photothermal response demonstrated the emitter's rapid heat storage and release capabilities. Additionally, an infrared scene generator is realized. These results position the photothermal film emitter as a promising solution for infrared imaging and dynamic scene generation.

Potent Amphiphilic Poly(Amino Acid) Nanoadjuvant Delivers Biomineralized Ovalbumin for Photothermal-Augmented Immunotherapy.

Cancer nanovaccines have emerged as an indispensable weapon for tumor treatment. However, insufficient immunogenicity and immunosuppression hamper the therapeutic effects of nanovaccines. Here, biodegradable nanovaccines (OMPP) composed of ovalbumin (OVA)-manganese oxide nanoparticles, amphiphilic poly(γ-glutamic acid) (γ-PGA), and ε-polylysine (PL) are constructed to realize enhanced cancer immunotherapy. Interestingly, amphiphilic γ-PGA and PL could serve as both carriers and immunoadjuvants to promote the cytosolic delivery of antigens and enhance the maturation of dendritic cells. Additionally, taking advantage of the photothermal property of OMPP, immunogenic cell death and in situ release of tumor-associated antigens can be triggered under near-infrared light irradiation for personalized tumor treatment. Moreover, OMPP nanovaccines can efficiently alleviate tumor hypoxia and downregulate programmed death-ligand 1 expression to reprogram the immunosuppressive tumor microenvironment. OMPP-mediated therapy has been shown to provoke robust immune responses to suppress B16-OVA melanoma and prevent postsurgical tumor recurrence. This work presents a facile strategy for the fabrication of nanovaccines by integrating carrier and adjuvant while exploring the inherent properties to promote antigen release and modulate immunosuppression, which demonstrates great potential for effective cancer immunotherapy.

Tea nanoparticles modified halloysite clay coated polyurethane sponge as multifunctional sensors

Tea, as one of the three major beverages in the world, has antioxidant, anti-cancer, inhibitory inflammation, immune regulation, diabetes prevention, antibacterial and other effects. In this study, black tea and FeCl3·6H2O were chelated to functionally modify the outer surface of halloysite clay nanotube (Hal). A new nanomaterial with excellent photothermal properties, tea nanoparticles@Hal, was successfully synthesized. Tea nanoparticles@Hal powder can raise to 225.8 °C in 25 s, and the corresponding solution can raise to 50.5 °C in 8 min with a photothermal efficiency of 77.3 %. The tea nanoparticles@Hal was assembled on the polyurethane (PU) sponges by simply soaking to prepare conductive sensor. The flexible sensor shows a fast response time (132.8 ms) and a long service time (400 cycles), which have wide range of applications. The resistance changes with the pressure is in a regular functional relationship, and the sensor can measure the weight of objects with high accuracy. In addition, the sensor can stably monitor various physiological activities of the human body. When finger is bent, the sensor can produce the difference output signals. The prepared tea nanoparticles@Hal/PU sensor has broad prospects in fields such as human-computer interaction and medical detection.

Electrically Controlled Smart Window for Seasonally Adaptive Thermal Management in Buildings.

Smart windows offer a sustainable solution for energy-efficient buildings by adapting to various weather conditions. However, the challenge lies in achieving precise control over specific sunlight bands to effectively respond to complex weather changes and individual needs. Herein, a novel electrochromic smart window fabricated by integrating a self-assembled cellulose nanocrystals (CNCs) layer with an electrochromic poly(3,4-ethylenedioxythiophene):poly(styrene sulfonic acid) (PEDOT:PSS) layer is reported, which exhibits high near-infrared transmittance, low solar reflectivity (26%), and infrared emissivity (20%) in winter, and low near-infrared transmittance, high solar reflectivity (91%), and infrared emissivity (≈94%) in summer. Interestingly, the material offers dynamic temperature control based on its photothermal properties, maintaining the internal temperature of buildings within a comfortable range of 20-25 °C from morning to night, particularly in winter with significant daily temperature fluctuations. Simulations show that the CNC-PED device demonstrates excellent energy-saving and CO2 emission reduction capacities across various global climate zones. This study presents a feasible pathway for constructing season-adaptive smart windows, making them suitable for energy-efficient buildings.

Enhancing Strawberry Freshness: Multifunction Sustainable Films Utilizing Two Types of Modified Carbon Nanotubes for Photothermal Food Packaging.

Currently, antimicrobial films with stable and efficient antibacterial activities are receiving considerable attention in the food packaging industry. Herein, a chemically/physically linked konjac glucomannan-sodium alginate (KGM-SA)@carbon nanotubes (CNTs)/Fe3+ composite film with outstanding resistance to ultraviolet radiation, oxidation, and bacteria, as well as excellent photothermal effects and mechanical properties, was successfully prepared using a solvent flow method. Tannic acid-modified carboxyl-functionalized CNTs (TCCNTs), l-cysteine-modified carboxyl-functionalized CNTs (LCCNTs), and Fe3+ were incorporated into the prepared film. The film structure of KGM-SA@CNTs/Fe3+ was characterized using various methods, confirming the formation of a dual-cross-linked network through metal-coordination bonds and hydrogen bonding. This unique structure endowed the film with excellent water vapor permeability (3.58 g mm/m2 day kPa), water resistance (water contact angle = 93.66°), and thermal stability. Further, the film exhibited outstanding photothermal conversion efficiency and stability under near-infrared irradiation (300 mW/cm2) as well as excellent bactericidal properties against Staphylococcus aureus and Escherichia coli, achieving a bacterial inhibition rate of >99%. In a strawberry preservation experiment, the KGM-SA@CNTs/Fe3+ composite film exhibited remarkable preservation effects, extending the shelf life of strawberries by 4-6 d. Thus, this photothermal antibacterial film offers a new approach for the application of CNTs in food packaging.

“Janus” PEEK implant with sandwich Mg-containing coating for infected tissue repair

Having good antibacterial properties and promoting soft and hard tissue repair are the keys to successful implantation of intraosseous transcutaneous. Polyether ether ketone (PEEK) is a class of FDA-approved polymer implants. However, the surface of PEEK is bioinert, which is easy to cause postoperative infection and poor tissue integration. In this study, polypyrrole (Ppy) was polymerized on sulfonated PEEK, Mg3(PO4)2 nanosheets were grown in situ on one side, and polycaprolactone (PCL) was then spun on the surface to form a Janus-like surface on PEEK. The Ppy/Mg3(PO4)2/PCL composite coating could inhibit bacterial adhesion, and the excellent photothermal properties of Ppy/Mg3(PO4)2/PCL and Ppy coatings further promote the removal of bacteria due to the accumulated heat. After the infection was eliminated, the Janus-like surface of modified PEEK switched macrophages to anti-proinflammatory response and promoted both soft and hard tissue repair. The Ppy modified sulfonated PEEK could promote collagen secretion in the soft tissue, while the PCL films on Ppy/Mg3(PO4)2/PCL was densified by temperature response under near-infrared light treatment to close the exposed interface of Mg3(PO4)2 nanosheets that was more conducive to bone repair. In summary, PEEK with Janus-like surface consisting of Ppy/Mg3(PO4)2/PCL and Ppy has multiple biological functions of sequential antibacterial and soft and hard tissue repair, and is a promising candidate material for intraosseous transcutaneous implants.

Optimizing Materials to Boost the Valorization of CO2: Tuning Cobalt-Cobalt Interactions on In2O3-Based Photothermal Catalysts.

The valorization of CO2 is an important challenge within the current panorama, since this molecule is probably the main contributor to climate change. In this study, the synthesis of materials based on a nanostructured batonnet-type indium oxide is carried out. In them, different amounts of Co are introduced, varying between 2 and 8% mol. It is verified that the most active sample in the transformation of carbon dioxide to carbon monoxide contains 6 mol %. of Co. This sample's activity under dual excitation exceeds the thermal counterpart by more than 30%. After carrying out a complete physical and chemical characterization with the help of X-ray absorption spectroscopy and other techniques, it is shown that catalysts with amounts of cobalt equal to or below 4 mol % contain isolated single-atom species, while those with higher amounts of metal display a Co-Co interaction which triggers the evolution of the samples under reaction conditions. The optimum control of this Co-Co interaction and the nature of the final cobalt-containing species determine dual photothermal catalytic properties. This work establishes a structure-activity relationship to interpret the catalytic behavior of highly dispersed subnanometric cobalt species, and thus an avenue to optimize the photothermal valorization of carbon dioxide.

Carbon dot-based nanomaterials with enzyme-like activity for fluorescence imaging and potential combination withtherapy of cancer.

Carbon dot-based nanomaterials (o-CDs@Mn) were fabricated by assembling fluorescent o-CDs with enzyme-like activity and Mn nanoparticles with photothermal properties for realizing fluorescence imaging and combined therapy of cancer. Due to the inherent optical properties of o-CDs, o-CDs@Mn can be effectively used for bioimaging. In addition, o-CDs@Mn possess peroxidase-like (POD-like) and glutathione (GSH) degradation capabilities, which can effectively deplete excessive H2O2 and GSH in the tumor microenvironment (TME), generating ·OH and reduced GSSH for regulating the TME and triggering ROS-mediated apoptosis in cancer cells. More importantly, it is synergistically supplemented with fluorescence imaging and photothermal therapy (PTT), which realizes the integration of monitoring and combined treatment, providing a promising potential pathway for accurate and efficient cancer treatment.

Highly efficient solar steam evaporation via elastic polymer covalent organic frameworks monolith

Three-dimensional solar steam evaporators with efficient water purification performance have received increasing attention recently. Herein, elastic polymer covalent organic frameworks (PP-PEG) containing PEG chains with intriguing adaptability to guests are prepared by forming porphyrin rings. PP-PEG foams demonstrate full spectrum absorbance and excellent photothermal conversion properties. Through well-designed thermal management and optimization of the hydrophilicity and PEG chain length, we obtain a highly efficient solar evaporator with an evaporation rate of 4.89 kg m−2 h−1 under 1 sun in self-contained mode. The optimized solar evaporation rate is increased to 18.88 kg m−2 h−1 under 1 sun with a facile truncated cone reflector, exceeding all known solar steam evaporators. This innovative design holds immense promise for desalination and water purification owing to its simple preparation, high efficiency and durability.

Shape memory, reprocessable and photothermal networks of polyurethane with silyl ether bonds and croconaine segments

Organic dyes were integrated into networks of polyurethane (PU) in the form of croconaine segments, in order to bestow photothermal properties on the materials. In addition, the PU networks were crosslinked with polysilsesquioxane (PSSQ) so that the materials can be reprocessed (or self-healing) via the metathesis of silyl ether bonds under catalysis. Toward this end, we synthesized a novel diol bearing croconaine moiety, which was used as one of chain extenders and a series of linear PU telechelics with dihydroxyl termini were synthesized. The α,ω-dihydroxyl PU telechelics were then allowed to react with 3-isocyanatopropyltriethoxysilane to gain α,ω-ditriethoxysilane PU telechelics. Through sol-gel process, α,ω-ditriethoxysilane PU telechelics readily underwent crosslinking with PSSQ as the crosslinkages. The crosslinking of PU was in marked contrast to traditional crosslinking of PU with multifunctional ols (or amines) as the crosslinkers. Owing to the crosslinking, shape memory properties were bestowed on the organic-inorganic PU networks. Thanks to the metathesis of silyl ether bonds under catalysis, the organic-inorganic PU networks were reprocessable (or recyclable). Benefiting from the built-in of dye segments, the PU networks significantly displayed excellent photothermal conversion properties. By leveraging the photothermal properties, the shape shifting of the PU networks can be triggered via the irradiation under infrared laser and in a non-contact fashion. In addition, the PU networks were capable of displaying the light-triggered self-healing properties. Thanks to these excellent properties, we demonstrated a successful application of the PU networks a soft robot.

A Graphene-Based Lipid Modulation Nanoplatform for Synergetic Lipid Starvation/Chemo/Photothermal Therapy of Oral Squamous Cell Carcinoma.

Chemotherapy is one of the most commonly used treatments for oral squamous cell carcinoma (OSCC), but its use is limited by drug resistance and severe systemic toxicity. To eliminate these side effects and improve anti-tumor efficacy, several therapeutic approaches have been developed for use with chemotherapy. In this study, we developed a graphene-based lipid modulation nanoplatform (NSD) that carries SB-204990, a small molecule inhibitor specific for ATP citrate lyase (ACLY), and doxorubicin (DOX), a chemotherapeutic agent, and the trio enables synergistic treatment of OSCC with lipid starvation, chemotherapy, and photothermal therapy. We first determined whether ACLY expression was upregulated in OSCC, and then assessed the growth inhibitory effects of SB-204990 on SCC-15 cells and changes in lipid (acetyl coenzyme A, free fatty acids, and cholesterol) levels. We characterized NSD and then evaluated the stability, photothermal properties, drug loading, and release ability of NSD. Finally, the therapeutic effects of NSD on OSCC were investigated by in vitro and in vivo experiments, and the changes in lipid levels in OSCC tissues after ACLY inhibition were further evaluated. The results showed that ACLY was highly expressed in OSCC, and ACLY inhibition produced reproductive suppression and decreased lipid levels in SCC-15 cells. The NSD nanoplatform possessed good stability, photothermal properties, high drug loading capacity and controlled release. In addition, the triple therapy achieved satisfactory anticancer effects in both in vivo and in vitro assays, and the inhibition rate of tumors was as high as 99.4% in the NSD+Laser treatment group. The changes in tumor cell lipid levels and cell proliferation arrest induced by ACLY inhibition suggest that ACLY may be a promising target for lipid starvation therapy and resistance to chemoresistance, and its inhibitors are expected to become new anticancer drugs. The NSD nanocarrier system enables synergistic treatment with lipid starvation, chemotherapy, and photothermal therapy, which represents an innovative approach to combating tumors.

One-step development of photothermal omniphobic membrane for vacuum membrane distillation towards sustainable water desalination using solar energy

Nowadays, development of photothermal omniphobic membranes (POMs) for water desalination using solar energy has gained considerable attention to face water and energy challenges in a sustainable way. Scientists have been developing POM via different techniques based on photothermal component loading and surface energy reduction, all of which suffer from multi-step processes. Obviously, researchers and especially industrial developers aspire to one-step techniques that make the production process highly accelerated and economical. In this study, a one-step technique to develop POMs is demonstrate, using which the omniphobic and photothermal properties are simultaneously imparted to the membrane through being integrated with the membrane fabrication process. The technique works based on elaborate design of membrane surface chemistry and roughness via electrospinning of poly(vinylidene fluoride) (PVDF)/poly(1H,1H,2H,2H-perfluorooctyl acrylate) (PPFOA) blend solution containing carbon black nanoparticles (CB NPs). Optimum concentrations for PPFOA and CB NPs with respect to the PVDF weight were obtained as 60 and 15 wt%, respectively. The developed membrane exhibited permeate flux and salt rejection as high as 2.94 kg/m2·h and > 98 %, respectively, under one sun radiation. Evaporation rate and efficiency of the developed membrane were calculated as 1.49 kg/m2.h and 83.5 %, respectively. The membrane exhibited stable long-term performance for 600 min in contact with the sodium dodecyl sulfate (0.8 mM)-containing NaCl aqueous solution (3.5 wt%). Besides single-step implementation, the introduced technique benefits from endowing the entire membrane structure with omniphobic and photothermal properties not only the membrane surface. This can drastically improve the membrane performance and life time.

Facile synthesis of Fe3O4 photothermal nanoparticles coated with poly-3,4-dihydroxybenzaldehyde for improved photothermal therapy of cancer cells

Given the significant rise in the number of individuals diagnosed with cancer, the management of cancer therapy has become a prominent concern in society and a formidable task in human health care. Photothermal therapy has garnered significant interest in cancer treatment because of its exceptional efficacy and minimal invasiveness. Thus, current research mainly focuses on developing biocompatible materials with excellent photothermal properties. Therefore, we synthesized Fe3O4 nanoparticles coated with poly-3,4-dihydroxybenzaldehyde (Fe3O4@PDBA) where 3,4-dihydroxybenzaldehyde was covalently polymerized onto the surface of Fe3O4. The induction of PDBA leads to a dramatical improvement in the photothermal properties of Fe3O4. Besides, the thickness of the PDBA shell layer is also a key factor in the photothermal performance and various physicochemical properties of Fe3O4@PDBA and the photothermal performance of Fe3O4@PDBA increases with increasing thickness of the PDBA shell. Additional structural characterization of the products, DFT calculations of the UV-Vis absorption spectra and the HOMO-LUMO gap under the simple model of the polymer, and product identification by the use of H1NMR, MS, and other techniques were performed. Through multiple characterizations, the reaction solution color and UV-Vis absorption spectra were essentially consistent with the computed findings. The calculations confirm that the polymerization process of PDBA is progressively red-shifted and the absorption is gradually enhanced in the NIR region. Fe3O4@PDBA exhibited strong cytotoxicity against cancer cells (Hela, 98.0%) in vitro photothermal treatment. Hence, Fe3O4@PDBA exhibits superior photothermal characteristics, targeting, biocompatibility (99.0%), and degradability, which brings about significant potential for photothermal cancer therapy.

A Gradient Photothermal Hydrogel with Carbon-Dots Deposited Molybdenum Disulfide Nanoflowers as Photothermal Centers for Efficient Solar-Driven Water Evaporation and Treatment

Given the urgency of water pollution and freshwater scarcity, the pursuit of efficient and clean desalination techniques has gained prominence. In this study, a multi-defective molybdenum disulfide nanoflower was synthesized within a carbon-dots solution environment, named CDs/MoS2, exhibiting exceptional photothermal and catalytic properties. Relying on the excellent photothermal properties, antibacterial rates of up to 94% and 99% against Staphylococcus aureus and Escherichia coli. Additionally, the CDs/MoS2 nanoflowers exhibited a remarkable removal efficiency of 91% for high concentrations of methylene blue (MB) through photodegradation. A gradient photothermal composite hydrogel (CDs/MoS2@PVA Hydrogel) was designed to serve as a solar-driven clean water generator to isolate drinking water from various non-potable water. The gradient hydrogel effectively enhanced solar energy absorption through light trapping, creating dispersed hot spots to capture and activate water molecules. As a result, it achieved a high evaporation rate of 1.49 kg m-2 h-1 at a solar radiation of 1 kW m-2, with an impressive solar-to-vapor conversion efficiency of 92.5%. The hydrogel was successfully employed in diverse water treatment applications, including desalination, anti-bacteria and removal of organic contaminants from water. This study presents an innovative approach to developing novel solar vapor materials for water purification purposes.