Photothermal Conversion Performance Research Articles

Engineering of surface-altered polydopamine nanocomposites for successive drug release and in vivo antitumor effects in cervical cancer therapy: Investigation of antiproliferative effects and apoptosis

Extreme side effects and drug resistance are common with single-drug chemotherapy, reducing its efficacy as a treatment. Photothermal therapy (PTT) is a promising technique for treating cancer since it is noninvasive, can be controlled from a distance, and is highly targeted. Nanomedicines having synergistic chemo-photothermal characteristics may be more effective at combating tumors. To deliver gemcitabine (GEM) for targeted cancer therapy, we fabricated polydopamine (PDA)-loaded with polyethylene glycol and folic acid (FA). The findings demonstrated this delivery vehicle's narrow size distribution and nanoscale particle size. During the stability test, no substantial drug leakage or particle aggregation occurred. This system's photothermal conversion performance in near-infrared laser (NIR) irradiation was remarkable because of the PDA layer. HeLa cells were severely reduced in their ability to recover, and apoptosis was triggered in cancer cells after FA modification increased intracellular absorption of nanoparticles. To prevent drug-related cardiotoxicity, the nanoparticle group decreased GEM levels in the heart compared to the free GEM group. HeLa cervical carcinoma was reduced in an in vivo investigation by injecting fabricated nanoformulations intravaginally into female mice. Histological data from the NPs-treated mouse model demonstrates tumour reduction by H&E. Rats with tumors would benefit significantly from the suggested nanoformulation loaded with GEM. Using chemo-photothermal treatment, it was demonstrated in vitro and in vivo that cervical cancers could be totally removed, and the lives of survivors may be significantly prolonged.

Solar enhanced uranium extraction from seawater with the efficient strategy of MXene loaded nano-porous polyamidoxime membrane

Uranium extraction from seawater is a significant avenue for achieving sustainable energy development, but low uranium concentration and low water temperature in the ocean make it an eunormous challenge to extract uranium from seawater. To overcome these challenges, incorporating photothermal conversion components into the adsorbent holds great promise for enhancing solar-driven uranium extraction from seawater. Herein, a photothermal adsorbent PAO@MXene (PM) membrane was designed by combining 2D MXene with excellent photothermal conversion performance and polyamidoxime (PAO) with excellent uranium adsorption performance. We first fabricated a nano-porous PAO membrane via electrospinning and then prepared the PM membrane with high photothermal conversion and adsorption performance using a simple ultrasonication method. Under light condition, the adsorption capacity of PM membrane reached 452.42 mg g−1 while the adsorption capacity is 352.32 mg g−1 under dark. The adsorption capacity of light is 28.41 % higher than that of dark. Moreover, PM membrane exhibits a high uranium adsorption capacity of 2.19 mg g−1 after contact with natural seawater for a week. The results indicate that the suggested strategy can achieve solar enhanced uranium extraction from seawater through a simple method.

Engineering Copper-Containing Nanoparticles-Loaded Silicene Nanosheets with Triple Enzyme Mimicry Activities and Photothermal Effect for Promoting Bacteria-Infected Wound Healing.

Skin wounds accompaniedby bacterial infections threaten human health, and conventional antibiotic treatments are ineffective for drug-resistant bacterial infections and chronically infected wounds. The development of non-antibiotic-dependent therapeutics is highly desired but remains a challenging issue. Recently, 2D silicene nanosheets with considerable biocompatibility, biodegradability, and photothermal-conversion performance have received increasing attention in biomedical fields. Herein, copper-containing nanoparticles-loaded silicene (Cu2.8O@silicene-BSA) nanosheets with triple enzyme mimicry catalytic (peroxidase, catalase, and oxidase-like) activities and photothermal function are rationally designed and fabricated for efficient bacterial elimination, angiogenesis promotion, and accelerated wound healing. Cu2.8O@silicene-BSA nanosheets display excellent antibacterial activity through synergistic effects of reactive oxygen species generated from multiple catalytic reactions, intrinsic bactericidal activity of released Cu2+ ions, and photothermal effects, achieving high antibacterial efficiencies on methicillin-resistant Staphylococcus aureus (MRSA) of 99.1 ± 0.7% in vitro and 97.2 ± 1.6% in vivo. In addition, Cu2.8O@silicene-BSA nanosheets exhibit high biocompatibility for promoting human umbilical vein endothelial cell (HUVEC) proliferation and angiogenic differentiation. In vivo experiments reveal that Cu2.8O@silicene-BSA nanosheets with synergistic photothermal/chemodynamic therapeutics effectively accelerate MRSA-infected wound healing by eliminating bacteria, alleviating inflammation, boosting collagen deposition, and promoting angiogenesis. This research presents a promising strategy to engineer photothermal-assisted nanozyme catalysis for bacteria-invaded wound healing.

Highly efficient MoS2/MXene aerogel for interfacial solar steam generation and wastewater treatment

Interfacial solar steam generation using aerogels holds great promise for seawater desalination and wastewater treatment. However, to achieve aerogels with both durable, high-efficiency evaporation performance and excellent salt resistance remains challenging. Here, a molybdenum disulphide (MoS2) and MXene composite aerogel with vertical pore channels is reported, which has outstanding advantages in mechanical properties, water transportation, photothermal conversion, and recycling stability. Benefiting from the plasmon resonance effect of MXene and the excellent photothermal conversion performance of MoS2, the aerogel exhibits excellent light absorption (96.58 %). The aerogel is resistant to deformation and able to rebound after water absorption, because of the support of an ordered vertical structure. Moreover, combined with the low water evaporation enthalpy, low thermal conductivity, and super hydrophilicity, the aerogel achieves an efficient and stable evaporation rate of about 2.75 kg m−2h−1 under one sun and exhibits excellent self-cleaning ability. Notably, the evaporator achieves removal rates of 99.9 % for heavy metal ions and 100 % for organic dyes, which has great potential in applications including seawater desalination and wastewater purification.

Efficient solar-driven carbon dioxide capture system for greenhouse using graphene-contained deep eutectic solvents

As photosynthesis progresses, the concentration of CO2 within greenhouses rapidly declines, significantly impairing crop growth. In light of the prevailing limitations associated with complex systems, high energy consumption, and safety concerns related to existing CO2 supplementation methods, a novel “solar-driven CO2 capture system” was proposed for the first time in current work, in which high photothermal conversion materials were incorporated into the deep eutectic solvents (DES). This nanofluid system aims to elevate the system's temperature, facilitating the desorption process and promoting the CO2 absorption–desorption cycle. The graphene nanofluid (GNF) prepared with varying mass fractions of reduced graphene oxide (RGO) can raise CO2 absorption capacity. The results indicate that the CO2 absorption capacity has improved from 0.286 g/g to 0.399 g/g, which can be attributed to abundant adsorption sites provided by the surface of RGO for capturing CO2. Furthermore, the addition of RGO improves the photothermal conversion performance of DES. Maximum photothermal conversion efficiency of 94.3 % and a maximum temperature of 75.9℃ have been achieved for DES-500 (with the addition of 500 ppm RGO in DES) under the irradiation of 1000 W/m2; while pure DES presents 32.7 % and 54.7℃, respectively. Notably, GNF also exhibits excellent recyclability and can effectively regulate CO2 concentration within the greenhouse, ensuring normal growth and development of crops.

Core-Shell Au@Pd Bimetallic Nanozyme Mediated Mild Photothermal Therapy through Reactive Oxygen Species-Regulating Tumor Thermoresistance.

Mild photothermal therapy (mPTT), which circumvents the limitations of conventional photothermal therapy, is emerging and exhibits remarkable potential in clinical applications. Nevertheless, mPTT is not able to efficiently eradicate tumors because its therapeutic efficacy is dramatically diminished by stress-induced heat shock proteins (HSP). Herein, a core-shell structured Au@Pd (AP) bimetallic nanozyme was fabricated for reactive oxygen species (ROS) augmentation-induced mPTT. The nanocatalytic AP nanozymes with photothermal conversion performance harbor multienzymatic (catalase, oxidase, and peroxidase) activities to induce ROS storm formation. The generated ROS could suppress the heat-defense response of tumor cells by cleaving HSP. Overall, our work highlights a ROS-regulating strategy to counteract hyperthermia-associated resistance in mPTT.

Evaluation and design of photothermal conversion performance for multiple “complex-morphology” nanofluids via bidirectional deep neural network

The optical absorption and scattering of plasmonic nanoparticles are crucial for optimizing photothermal conversion efficiency, which holds great potential in various applications. Evaluating the photothermal conversion performance of nanofluids with known geometry is a computationally expensive task. The design of nanofluids that exhibit optimal photothermal conversion performance poses a complex inverse problem. The necessity to explore a wide parameter space, which encompasses various factors such as the shape, size, and material of nanoparticles, contributes to this challenge. In this study, we employ a combination of machine learning with high-throughput radiative transfer calculations to conduct a comprehensive analysis of the entire photothermal conversion process for various nanofluids. The modulation of resonance absorption peaks and spectral absorption can be achieved by adjusting the shape, material constituents, and geometric parameters of nanoparticles. Meanwhile, we establish a design space dataset that encompasses 14,060 groups of nanofluids. Based on the dataset, we demonstrate as a proof of concept bidirectional deep neural network model that enables an efficient and reliable solution to both the forward and inverse problems. The results show that the absorptivity of SiO2@Au nanofluids is significantly influenced by the volume fraction, particularly when it falls within the range of 1 × 10−5 to 1 × 10−4. However, the impact is significantly reduced within the range of 1 × 10−4 to 1 × 10−3. Furthermore, the SiO2@Au nanofluids exhibit enhanced full spectral absorption characteristics at the core-shell ratio of 0.1. Our proposed model achieves a forward prediction of the solar absorption spectra with 99% accuracy and an inverse design of the geometric parameter with 93% accuracy. In comparison to the experimental results, the relative errors for the predicted and design efficiency are 0.42% and 0.82%, respectively. The design geometry parameters including the effective radius and volume fraction exhibit relative errors of 3.88% and 1.6%, respectively. This work provides a widely applicable and computationally efficient method for the evaluation and design of nanofluids in photothermal conversion.

Double Carbon Networks Reinforce the Thermal Storage and Thermal Transfer Properties of 1-Octadecanol Phase Change Materials.

Using thermal storage materials with excellent thermal properties in the energy utilization system enables efficient use of renewable energy sources. Organic phase change materials (PCMs) have the advantages of high heat storage density, no corrosion, and low cost, but low thermal conductivity and insufficient heat transfer capacity have always been the bottlenecks in their application. In this paper, melamine foam@ reduction graphene oxide (MF@rGO) and carbon foam@ reduction graphene oxide (CF@rGO) composite foams with double carbon networks were prepared by self-assembly method and further employed in 1-octadecinal (OD) PCMs. The microstructure, chemical composition, phase change behavior, thermal conductivity, and photothermal conversion performance of MF@rGO/OD and CF@rGO/OD were studied in detail using SEM, FTIR, Raman DSC, and LFA. The melting and solidification enthalpies of CF@rGO/OD composite PCMs were 208.3 J/g and 191.4 J/g, respectively, its thermal conductivity increased to 1.54 W/m·K, which is 6.42 times that of pure OD. The porous structure and high thermal conductivity of the double carbon network substantially enhance the efficiency of energy storage and release in composite PCMs. CF@rGO/OD composite PCMs have excellent heat storage performance and heat transfer capacity, and a wide range of application prospects in the fields of low-temperature solar heat storage, precision instrument temperature control, and intelligent buildings.

Hybrid Integration of Au Nanoplates and Ag Nanoparticles with Controlled Nanogaps via Cu2O‐mediated Galvanic Replacement Reaction: Plasmonic Catalysis and Photothermal Conversion

AbstractRational assembling of different noble metal nanocrystals with controlled nanogaps in one entity allows the efficient coupling of electromagnetic fields of each component and versatile manipulation over the overall physiochemical properties. In the present study, we report a stepwise synthetic strategy to hybridlike assemble Au nanoplate and Ag nanoparticles without direct physical contact. Particularly, the success of current work relies on the conformal coating of Cu2O over the Au nanoplate as an intermediate layer, followed by the in situ formation of Ag nanoparticles via the galvanic replacement reaction between Cu2O and Ag+. With the anchoring of Ag nanoparticles over the Cu2O‐wrapped Au nanoplate, the resulting hybrid nanostructures exhibit noticeable multiple plasmonic absorptions across the UV‐vis‐NIR region. The potential use as the plasmonic catalyst for current Au@Cu2O‐Ag hybrid products is validated using reduction of 4‐nitrophenol as the model reaction, where the catalytic performance is greatly improved by the UV‐vis light irradiation. They also exhibit satisfactory photothermal conversion performance under the irradiation of Xe lamp. The current work provides a niche strategy to create noble‐metal hybrid nanostructures with controlled interparticle distance and tunable plasmonic properties, could be extended to other noble metal or alloys.

Fabrication of graphene-rapped melamine sponge and its photothermal adsorption on viscous oil spill

Graphene oxide melamine sponges (GOMSs) were prepared by impregnating melamine sponge (MS) with graphene oxide (GO) dispersion. Thereafter, reduced graphene oxide melamine sponges (HGOMSs) were obtained by one-step heat treatment of GOMSs, and the effects of heat treatment and GO load on sponge structure, hydrophobicity/ lipophilicity, photothermal properties, mechanical properties and light-aided adsorption performances were evaluated. The results show that heat treatment under 400 °C is an optimum choice. A small amount of graphene could effectively wrap on the melamine sponge skeleton and closely combined with the sponge. This effectively wrapped structure can not only improve the photothermal and mechanical properties of the sponge, but also retain the rich pore structure of the sponge to provide sufficient space for oil adsorption. HGOMS prepared under 400 °C with 1 mg·ml−1 of GO concentration shows an average light absorption rate of 84.4% in the full solar spectral range. Under 1 sun illumination in air, the surface can quickly rise to 99.4 °C, and the bottom surface is 72.8 °C, showing excellent photothermal conversion performance. The saturated adsorption capacity on heavy oil reached 103.2 g·g−1 under 1 sun illumination. The material was reused through mechanical extrusion method. After 10 times of adsorption- extrusion operations, its saturated adsorption capacity still retained more than 80% of the first time. These characteristics make HGOMS an energy efficient and reusable adsorbent for oil spill.

Constructing a hierarchical coating with photothermal superhydrophobic property by spraying and modification on polyurethane foam for anti-icing and deicing

Superhydrophobic material with photothermal conversion property is considered as a promising candidate in practical application because of its double abilities: both superhydrophobic anti-icing and photothermal deicing. Therefore, in this work, we employed a polyurethane (PU) foam with three-dimensional porous grid structure as the skeleton and carbon nanotubes (CNTs) as the photothermal conversion materials to construct a hierarchical coating with photothermal superhydrophobic property by spraying CNTs/SiO2 and modification of polydimethylsiloxane (PDMS), where a dual-size micro/nano structure was formed by adsorbing and fixing these CNTs-entangled SiO2 nanoparticles into PU foam to enhance the superhydrophobicity and light absorption capacity of coating. In this case, the water contact angle of the hierarchical coating reached up to 157.0°, accompanied by a rolling angle of 3.2°, while the water droplet hitting its wall can fully rebound within 27 ms. Importantly, the formation of hierarchical structure and the incorporation of CNTs contributed to an enhancement of light absorbance to 97.1 %, which was able to warm the coating surface up to 101.9 °C at 1 kW m−2 after 300 s illumination. Noteworthily, the surface temperature of the coating can be raised to 62.5 °C within 15 min to achieve deicing under a low ambient temperature of −20 °C. In addition, a remarkable stability and wear resistance were maintained after 10 freeze–thaw cycles and 20 friction cycles. Consequently, it can be concluded that the developed hierarchical coating with exceptional superhydrophobicity and excellent photothermal conversion performance was expected to be a potential substitute for anti-icing and deicing.

Intelligent bamboo: A splendid flame retardant, fire warning and photothermal sterilization nanocoating via low-temperature evaporation induced self-assembly

The application of bamboo to assist carbon neutral strategy has attracted worldwide attention due to its naturally carbon-negative property. However, the inherent defects of flammable and mildewed make bamboo encounter a bottleneck in its application. Hence, an intelligent bamboo (IB) with integrated performances of stable connection, high-temperature resistance, reliable fire warning and splendid photothermal sterilization properties was constructed via low-temperature evaporation induced self-assembly strategy. The hydrogen bonding, coordination complexes, van der Waals forces, and electrostatic forces can be formed between Ti3C2Tx (MXene) and pre-treated bamboo substrate (TB). The optimized bamboo-based fire alarm sensor (AM@TB) exhibits significant improvement in flame retardant properties, e.g., the limiting oxygen index (LOI) value of AM@TB8-2 was 61.4%, surpassing TB by an impressive margin of 65.8% and the vertical burning test reach the UL94 V-0 rating. Besides the PHRR (heat release rate) of AM@TB8-2 was decreased 80.3% compared to TB. The residual mass of AM@TB8-2 is 34.5%, which is 1.6 times higher than TB. Additionally, the AM@TB8-2 presents a sensitive fire warning response (∼2 s) and reliable repeatability. Furthermore, based on the outstanding photothermal conversion performance of MXene, AM@TB8-2 demonstrates predominant sterilization efficacy after a near-infrared laser (NIRL) illumination. Therefore, this work provides inspiration for the design and fabrication of high-performance IB that combine fire safety and antimicrobial properties.

Fabrication of Robust Superhydrophobic Polyester Fabrics with Photothermal Conversion and Oil-Water Separation Performance through Deposition of Natural Polyphenols.

Superhydrophobic polyester (PET) fabrics were created by increasing fabric surface roughness and decreasing surface energy through interactions between natural polyphenols, ferrous sulfate heptahydrate, and hexadecyltrimethoxysilane. The superhydrophobic fabric can be obtained with different natural polyphenols, including tannic acid, ferulic acid, gallic acid, guaiacol, and caffeic acid. Durability tests were carried out on the superhydrophobic PET fabric, investigating resistance to washing, rubbing, UV aging, acids, alkalis, and organic reagents. The results demonstrate the stability and versatility of modified PET in complex environments. The modified superhydrophobic PET fabric exhibited exceptional oil-water separation and self-cleaning properties, exhibiting a water contact angle of 161.3° and a sliding angle of 4°. In addition, the modified fabric demonstrated a remarkable photothermal conversion efficiency, with the surface temperature increasing from 29.1 to 72 °C in 300 s, and it maintained a degree of photothermal conversion capability even upon completion of four cycles. This study offers novel perspectives on extending the utilization of natural polyphenols for constructing durable, robust, and multifunctional superhydrophobic fabrics.

Lignin with enhanced photothermal performance for the preparation of a sustainable solar-driven double-layer biomass evaporator

The undesirable photothermal conversion performance of lignin limits the potential for directing use as a photothermal conversion material, and no strategies have been found to enhance the photothermal conversion efficiency of lignin. Herein, three modified lignin of corn stover alkali lignin (DEHL), pine alkali lignin (DAL) and birch alkali lignin (DTAL) with excellent photothermal conversion efficiency and fast temperature response was prepared by a one-step iodocyclohexane (ICH) activation strategy. The maximum temperature of the DEHL, DAL and DTAL can reach to 138 °C, 157 °C, and 172 °C in 12 min under 0.15 W/cm2 compared to the native lignin. Moreover, the photothermal conversion efficiency of the DEHL, DAL and DTAL was calculated to be 36.52 %, 36.19 % and 43.19 % by ICH modification. The photothermal enhancement mechanism of the modified lignin was determined by various characterizations and simulation calculations, which can be summarized that the activation of lignin by ICH breaks the molecular structure and reduces the methoxy content of the lignin, which enhances the intermolecular bonding, and the hydrogen bonding between the phenolic hydroxyl groups strengthens the π-π intermolecular interactions between the benzene rings. In addition, a double-layer biomass aerogel evaporator (DAGS) with cost-friendly and superior evaporation performance was synthesized by chemical cross-linking using DTAL as the photothermal agent. The evaporation rate of 4DAGS can be as high as 2.063, 2.024, 2.259 and 2.447 kg/(m2∙h) in water, 3.5 wt% seawater, and 200 mg/L of MG or MB wastewater under 1sun. And no salt was observed on the surface of the 4DAGS after a long period of 36 h of operation in 3.5 wt% seawater, suggesting the outstanding salt-reject performance of the aerogel. Furthermore, there is no structural damage and chemical decomposition found on 4DAGS after 24 h immersion in NaOH and HCl solutions, demonstrating the excellent acid and alkali resistance of the synthesized aerogels. This work may offer a novel strategy for the photothermal performance enhancement of lignin and expand the potential application in solar-driven evaporation materials.

2D silicene nanosheets-loaded coating for combating implant-associated infection

Implant-associated infection (IAI) is an unsolved problem in orthopaedics. Current therapies, including antibiotics and surgical debridement, can lead severe clinical and financial burdens on patients. Therefore, there is an urgent need to reinforce the inherent antibacterial properties of implants. Recently, two-dimensional (2D) silicene nanosheets (SNs) have gained increasing attention in biomedical fields owing to their considerable biocompatibility, biodegradability and strong photothermal-conversion performance. Herein, a dual-functional photosensitive coating on a Ti substrate (denoted as TPSNs) was rationally fabricated for bacterial inhibition and osteogenesis promotion. For the first time, SNs were loaded onto the surface of implants. Hyperthermia generated by the SNs and polydopamine (PDA) coating under 808 nm laser irradiation achieved the in vitro anti-bacterial efficiency of 90.7 ± 2.4 % for S. aureus and 88.0 ± 5.8 % for E. coli, respectively. In addition, TPSNs exhibited promising biocompatibility for the promotion of BMSC (bone marrow mesenchymal stem cells) proliferation and spreading. The presence of silicon (Si) in TPSNs contributed to the improved osteogenic differentiation of BMSCs, elevating the expressions of RUNX2 and OCN. In animal experiments, the combination of TPSNs with photothermal therapy (PTT) achieved an anti-bacterial efficiency of 89.2 % ± 1.6 % against S. aureus. Furthermore, TPSNs significantly improved bone-implant osseointegration in vivo. Overall, the development of a dual-functional TPSNs coating provides a new strategy for combating IAI.

Environmental-friendly biomass-based Janus ink/urushiol modified cotton fabric for efficient solar-driven interfacial evaporation

Much attention has been paid to the interfacial solar-thermal conversion method for water resource purification. According to the hydrophilicity of ink carbon particles and the amphiphilicity of urushiol molecules (the main compound of Chinese lacquer), a novel environmentally friendly biomass Janus ink/urushiol modified cotton fabric was successfully prepared and exhibited one hydrophilic side and one hydrophobic side through simple immersion and spraying treatments. The Janus fabric displayed excellent water transport behavior, mechanical stability, thermal conductivity, and photothermal conversion performance. Under one stimulated solar radiation, the temperature of the Janus fabric increased to 85 °C in 2 min. Additionally, a photothermal vapor device prepared using a polyethylene ring and the Janus fabric demonstrated a high conversion efficiency of 94.3% with an impressive evaporation rate of 1.64 kg m−2h−1, which was 3.35 times the rate of water evaporation in the absence of the modified fabric. The Janus fabric showed satisfactory resistance to ultraviolet radiation and pH values. After 8 cycles (every 10 h) of exposure to outdoor sunlight, the modified fabric showed a slightly decreased evaporation rate, which could be restored to the previous level by re-spraying ink on the modified fabric. In the concentrated salt solutions, the solar-driven evaporator displayed excellent salt rejection capacity. During the desalination of high-concentration saline water, the Janus fabric showed acceptable diurnal correspondence. After desalination, the water quality reached the required standards for drinking water. In particular, the B3+ content droppingto 0.33 mg L−1(below the thresholdof 0.5 mg L−1). The solar steam generator also showed remarkable purifying capabilities for wastewater containing heavy metals and organic dyes. The Janus ink/urushiol fabric, prepared in an easy way, has a wide range of applications in seawater desalination and sewage treatment, which can be applied for mitigation of freshwater crises and environmental remediation.

Fabrication of targeted PDA-Hemin-Dox-FA nanoplatform for enhanced chemodynamic therapy synergized with chemo/photothermal therapy

Chemotherapy (CT) is widely used in clinical practice due to its simple and convenient steps, but its characteristics of systemic administration also results in a lack of targeting and a tendency to develop drug resistance, which greatly limits its therapeutic effect. In order to overcome these problems, a PDA-Hemin-Dox-FA (PHDF) nanoplatform was constructed in this work for the combined treatment of tumors. Firstly, hemin was introduced into the self-polymerization of dopamine to synthesize PDA-Hmein (PH) nanoparticles. Then, the chemotherapy drug doxorubicin (Dox) and targeted folic acid (FA) were loaded onto PH surfaces through Schiff base and amide bonds respectively to construct PHDF. When PHDF enters the tumor cells through the targeting guidance of FA, the acidic microenvironment of the tumor will induce the cleavage of the Schiff base bond in PHDF to release Dox. The presence of hemin makes PHDF have high Fenton-like activity, which generate large amount of·OH to perform chemodynamic therapy (CDT). Driven by near infrared laser light, PHDF exhibited wonderful photo-thermal conversion performance which not only brings excellent photo-thermal therapy (PTT) effect, but also promotes the uptake of Dox and the production of·OH, leading to enhanced CT and CDT efficacy. Taken together, the PHDF nanoplatform constructed in this study shows good CT/PTT/CDT combined therapy against tumor cells and it also provides a promising alternative for the combination therapy of tumors.

Superhydrophobic, flexible and high thermal stable ANFs/CNTs film for controllable light driven actuators

Superhydrophobic and light-responsive actuators (SLRAs) can be driven to move on water surface remotely and in a non-contact manner, and have shown promising applications in soft robotics, environmental protection, etc. It remains a big challenge to develop high performance SLRAs with excellent thermal stability, fast light responsivity and controllable motion. Here, we propose a layer-by-layer vacuum filtration method to prepare flexible, freestanding and superhydrophobic composite films composed of alternately deposited oleylamine modified acid carbon nanotubes (O-ACNTs) and aramid nanofibers (ANFs). The composite film has excellent thermal stability with the maximum weight loss rate temperature as high as 520 ℃. The closely packed structure and strong interlayer interaction ensure the surface stability and durability of the composite film. The composite film possesses excellent photothermal conversion performance, and can maintain the structure integrity without deformation when its surface temperature reaches 208 °C. When used as a self-propelled actuator, the SLRA film can response to the light quickly and move on the water surface, and the motion speed and direction can be controlled by adjusting the irradiation intensity and position. The outstanding thermal stability guarantees the stability and reliability of the self-propelled motions. The present study opens a new avenue to design high performance SLRAs.

Ligand Mediation for Tunable and Oxide Suppressed Surface Gold-Decorated Liquid Metal Nanoparticles.

Gallium-based liquid metal systems hold vast potential in materials science. However, maximizing their possibilities is hindered by gallium's native oxideand interfacial functionalization. In this study, small-molecule ligands are adopted as surfactants to modify the surface of eutectic gallium indium (EGaIn) nanoparticles and suppress oxidation. Different p-aniline derivatives are explored. Next, the reduction of chloroanric acid (HAuCl4 ) onto these p-aniline ligand modified EGaIn nanoparticles is investigated to produce gold-decorated EGaIn nanosystems. It is found that by altering the concentrations of HAuCl4 or the p-aniline ligand, the formation of gold nanoparticles (AuNPs) on EGaIn can be manipulated. The reduction of interfacial oxidation and presence of AuNPs enhances electrical conductivity, plasmonic performance, wettability, stability, and photothermal performance of all the p-aniline derivative modified EGaIn. Of these, EGaIn nanoparticles covered with the ligand of p-aminobenzoic acid offer the most evenly distributed AuNPs decoration and perfect elimination of gallium oxides, resulting in the augmented electrical conductivity, and highest wettability suitable for patterning, enhanced aqueous stability, and favorable photothermal properties. The proof-of-concept application in photothermal therapy of cancer cells demonstrates significantly enhanced photothermal conversion performance along with good biocompatibility. Due to such unique characteristics, the developed gold-decorated EGaIn nanodroplets are expected to offer significant potential in precise medicine.

Hydroxyl functionalized MWCNT nanofluids with excellent photothermal conversion performance in direct absorption solar collectors

Developing novel nanofluids with good stability, excellent photothermal conversion performance, and appropriate thermophysical properties is of great importance in promoting the practical utilization of nanofluids in solar collectors. In this work, hydroxyl multi-walled carbon nanotube (MWCNT-OH) nanofluids are proposed, which can achieve a high photothermal conversion of 88.2 % at a concentration of 20 ppm under 1-sun irradiation. Both the sedimentation experiment and spectrophotometer analysis prove that the prepared MWCNT-OH nanofluids have excellent stability. The influence of hydroxyl functionalization, MWCNT-OH concentrations, and temperature on the thermophysical and optical properties is analyzed. Moreover, the comparison between MWCNT-based nanofluids with different functionalization reported in the literature and our work is carried out, the results show that MWCNT-OH nanofluids in our work outperform MWCNT-based nanofluids with other types of functionalization reported in the literature. This work may promote the use of MWCNT-OH nanofluids as working fluids in solar collectors.