Photothermal Conversion Research Articles

Dynamic Water Microskin Induced by Photothermally Responsive Interpenetrating Hydrogel Networks for High‐Performance Light‐Tracking Water Evaporation

AbstractSolar‐driven interfacial water evaporation is attracting increasing attention as a promising environmentally‐friendly solution to freshwater scarcity. It has been proven that a thin water layer on photothermal materials can prevent solar energy from invalidly heating the excess water to enhance the evaporation rate. However, the current water layers are usually formed on inelastic materials via confined capillarity, which are static and uncontrollable. Herein, we propose a flexible hydrogel‐based photothermal conversion material with thermal responsiveness by facile frontal polymerization, which can generate a unique dynamic water microskin (DWMS) during the solar evaporation process. The copolymerized hydrogel, introduced by the second polymeric poly(vinyl alcohol) network and thermally responsive poly(N‐isopropylacrylamide) (PNIPAM), exhibits reinforced mechanical strength and photothermally triggers reversible shrinking/swelling cycles that enable a thin water layer (≈32 µm) to balance the feedwater supply and photothermic energy input dynamically. As a result, a stable superior vaporization rate of 8.7 kg m−2 h−1 is achieved based on a cylindrical hydrogel with 6 cm height under 1 sun. Moreover, the simultaneous responsive bending allows efficient omnidirectional solar evaporation by light‐tracking to ensure maximum perpendicular solar absorption, which provides an alternative strategy for durable high‐efficiency solar evaporators for effective thermal management and solar utilization.

Plasmonic Copper‐Ruthenium Superstructure for Efficient Photothermal Conversion and Plastic Recycling

AbstractPlasmonic superstructures offer broad prospects in photothermal catalysis, yet their controllable synthesis remains a challenge. Here, a controlled synthesis method for Cu‐Ru plasmonic superstructures via a one‐step polyol reduction process is presented, where Cu nanoparticles serve as the core, while the shell is formed from Ru nanoclusters. Through a comprehensive investigation of the growth mechanism, precise control over the composition and size of the superstructures is achieved. Finite‐difference time‐domain simulations and photothermal conversion experiments demonstrated that the optimized Cu3Ru1 superstructures possess strong light absorption capabilities and efficient photothermal conversion performance. These properties are effectively utilized in the photothermal recycling of waste polyethylene and polyethylene terephthalate, marking a significant advance in employing Cu‐based plasmonic materials for sustainable catalytic technology.

Effect of ultrasonication time on the performance of carbon black water nanofluid in solar absorption

This research reveals an innovative way of finding the ultimate time of ultrasonication that offers photothermal capability across carbon black (CB) water nanofluids, a great contribution to the field of solar energy absorption and nanofluid technology. The samples were generated using a two-step procedure with varying ultrasonication periods employed, ranging from 15 to 120 minutes, in concentrations of 0.005 wt% CB nanoparticles and 0.005 wt% sodium dodecyl sulfate (SDS) surfactant. Thirty days after preparation visible observation and UV spectroscopy, scanning electron microscopy (SEM) images, and particle size distribution were used to confirm the samples’ stability. The stability properties results demonstrated the beneficial effects of ultrasonication on the dispersion properties of nanofluids. Ultrasonication of less than 30 minutes resulted in the early sedimentation of nanoparticles. According to the results, the investigated nanofluids have high photothermal conversion capability with ultrasonication time. According to the findings, 30 minutes is the “optimal” ultrasonic duration to maximize photothermal conversion efficiency.

Multifunctional nano co-delivery system for efficiently eliminating neuroblastoma by overcoming cancer heterogeneity

The high heterogeneity of neuroblastoma (NB) is currently the main challenge in clinical treatment, impeding the complete eradication of the tumor through monotherapy alone. In this study, we propose a combination strategy using a targeted nano co-delivery system (ADRF@Ag2Se) comprising phototheranostic agents, differentiation inducers and chemotherapy drugs for sequential therapy of NB. Upon intravenous injection, ADRF@Ag2Se demonstrates effective tumor targeting by the specific binding of AF7P to MMP14, which is overexpressed on the surface of NB cells. Subsequent implementation of local photothermal therapy (PTT) leverages the robust photothermal conversion capabilities of the amphiphilic photothermal reagent PF. This is followed by the temperature-triggered release of differentiation-inducing agent 13-cis-retinoic acid and chemo-drug doxorubicin to synergistically eliminate the residual lesions. This nanotherapeutic strategy facilitatesin vivotargeted delivery and PTT under the supervision of NIR-II fluorescence, and it also enhances the chemotherapeutic response through differentiation induction of poorly differentiated cancer cells. In the NB tumor model, this co-delivery strategy effectively inhibited tumor growth and significantly prolonged the survival of the mice.

Two-Dimensional MXene (Ti3C2Tx)-based Nano-Photosensitizers for Enhanced Photothermal Ablation of Tumor Cells

Cancer remains one of the leading causes of death globally, accounting for approximately one in every six deaths. Traditional cancer therapies, including surgery, chemotherapy, chemoimmunotherapy, and radiation, face numerous challenges and limitations. In this context, we explore the advantages of photothermal therapy (PTT) using two-dimensional (2D) MXene-based nanocomposites for cancer treatment. MXenes, composed of abundant and non-toxic elements, such as titanium (Ti), carbon (C), fluorine (F), and oxygen (O), demonstrate low toxicity and are promising candidates in photothermal cancer therapies. Their ultrathin planar nanostructure, high photothermal conversion efficiency, strong near-infrared (NIR) responsiveness, and chemically modifiable surfaces enhance their therapeutic potential. Recent innovations include the development of folic acid-functionalized Au@c-Ti3C2 nanostructures, a skin-mountable electrostimulation patch (eT-patch), ionic gels containing MXene (Ti3C2Tx), and composite scaffolds made of MXene, collagen, silk fibroin, and quercetin. These MXene-based photosensitive compounds offer efficient targeting and selective treatment of cancer cells, highlighting their significant role in advancing cancer therapies.

Floating photothermal fabric based on spike-like dendrite fiber for highly efficient solar-thermal clean water production

Solar energy-driven interfacial water evaporation devices are expected to play a crucial role in obtaining fresh water from seawater. Using suitable micro-nano substrate materials can enhance the evaporation rate of flexible interfacial evaporators. However, current flexible micro-nano evaporator substrates are often made of porous gels, which are prone to undesirable heat loss during evaporation due to water filling the pores. In this study, we present a flexible photothermal fabric evaporator that integrates micro-nano structured nickel dendrite photothermal fibers as the photothermal layer with hydrophilic cotton wire serving as the water channel. These components are seamlessly combined through a traditional weaving process, creating an innovative design. The dendrite substrate is fabricated via an electrodeposition process, which can be tailored to produce an enhanced micro-nano surface. Following this, the dendrite is coated with a PANI photothermal conversion material using the electrophoresis method. The hydrophilic cotton wire effectively ensures a continuous water supply and efficiently channels water toward the dendrite's surface through a pronounced gradient capillary effect. As a result, the photothermal fabric achieves a remarkable surface temperature of 97.2 °C, an impressive evaporation rate of 2.13 kg·m−2·h−1, and a high evaporation efficiency of 85.6 % under illumination intensities of 1 kW·m−2. Additionally, it demonstrates robust long-term stability, enduring at least 15 consecutive cycles without significant degradation. This efficient construction and utilization of the micro-nano interface, combined with a sustained and adequate water supply, highlight the potential of dendrite photothermal fabric for seawater desalination applications.

The effect of ultrasonic waves on the structure, morphology, and thermal conductivity of graphene oxide as nanofluids for direct absorption solar collector application

This research aims to explore how ultrasonic waves affect the structure and morphology of graphene oxide (GO) as a nanofluid, influencing its thermal conductivity (TC), stability, and photo-thermal conversion properties. GO was rapidly synthesized under ultrasonic bath irradiation using modified and improved Hummers' methods. Ultrasonic irradiation creates different structural and morphological defects in the GO that depend on the sonication time. The relationship between the exposure time to ultrasound and the creation of structural and morphological defects in graphene oxide nanosheets was investigated using UV–Vis, FTIR, Raman spectroscopies, AFM, and TEM analysis. The study examined how the structure and morphology of graphene oxide nanosheets affect the thermophysical and photo-thermal conversion properties of nanofluids by comparing heat transfer and stability. The simultaneous characterizing of the structure and morphology indicates that TC and stability are related to the sonication time. Indirect sonication with low intensity can carefully control the oxidation reaction of GO. Sonication for 30 min creates GO nanosheets that yield stable nanofluids with a 32.31 % enhancement in TC, with no extra treatment needed. This particular nanofluid has excellent photo-thermal conversion properties thanks to its high optical absorption, good stability, and thermal conductivity. This can increase the solar-thermal conversion efficiency (η) up to 72.5 %, making it a promising candidate for use as the working fluid in direct absorption solar collectors (DASCs)

Understanding photo-thermal and melting mechanisms in optical charging of nano and micro particles laden organic PCMs

Engineering efficient optical charging process necessitates efficient photo-thermal energy conversion, transfer, as well as storage of the incident solar radiant energy. The present work is a determining step in deciphering, quantifying, and understanding the aforementioned steps involved in the optical charging of PCMs. Herein, the effect of particle size, concentration and thermochromism have been critically investigated. In particular, detailed optical characterization and photo-thermal experimentation pertinent to non-thermochromic nanoparticles laden PCM (referred to as NP-PCM) and thermochromic micro capsules laden PCM (referred to as TMCP-PCM) has been undertaken. Detailed optical analysis points out that opposed to NP-PCM, TMCP-PCM significantly scatter the incident radiations – the diffuse transmittance (at room temperature) in the two cases being approximately 2 % and 39 % respectively. Furthermore, whereas, optical properties of non-thermochromic nanoparticles are nearly invariant to temperature changes; in the case of thermochromic microcapsules, the magnitude of scattering further increases and diffuse transmittance reaches as high as 51 % at elevated temperatures. Although, thermochromism helps in enhancing the penetration depth at elevated temperatures, but, due to significant fraction of scattering, the photo-thermal energy conversion is not that effective. In terms of temperature field, spatial-temporal temperature distribution curves reveal that temperature spread (in the liquid phase) in case of optical charging of non-thermochromic particles (carbon soot nanoparticles) laden PCMs is significantly high (as high as approximately 24 °C) relative to that observed in case of thermochromic particles (microcapsules) laden PCMs (approximately, 4 °C). The magnitude of the temperature spread (being representative of the deviation from thermostatic optical charging) clearly points out that opposed to non-thermochromic laden PCMs, nearly thermostatic optical charging can be achieved in case of thermochromic particles laden PCMs.Furthermore, in case of optical charging without thermochromic assistance, the temperature spread, peak temperatures and the melting rates increase with increase in particles concentration. Whereas, in the latter case, although the temperature spread and peak temperatures are nearly independent; the melting rates do depend on the particles’ concentration. Overall, the present work is a significant step towards accelerated-thermostatic thermal energy storage.

Dual-functional boron nitride boosts photothermal conversion performance and thermal conductivity of wood-inspired cellulose-based phase change materials for infrared stealth and personal thermal management

Phase change materials (PCMs) can absorb heat energy from the sunlight and release thermal energy to keep the thermal comfort of humans in harsh cold environments. However, the leakage problem, low photothermal conversion performance, and poor thermal conductivity limit their practical applications. Herein, a wood structure-inspired porous cellulose nanofibers (CNFs) aerogel was used to relieve the leakage problem of lauryl alcohol PCM. A novel boron nitride (BN)/silver nanoparticles (AgNPs) complex was fabricated by using gallic acid as a green reduction agent and used to enhance photothermal conversion performance and thermal conductivity of CNFs/lauryl alcohol composite. The localized surface plasmon resonance (LSPR) and unique heat transfer paths of BN/Ag complex endow the resulting CNFs-based PCM with extraordinary photothermal conversion capacity (surface temperature of 58.2 ℃ under 1 kW m−2) and higher thermal conductivity. Combined with the high phase change enthalpy (172.90 J g−1), the resulting CNFs-based PCM showed potential applications in infrared stealth and personal thermal management fields. This work will open up a new avenue for fabricating a novel photothermal BN/Ag complex and provide a new idea for developing a multifunctional CNFs-based PCM for multi-scenario applications.

Prussian Blue-Carbonized wood photothermal composites for efficient solar evaporation and seawater desalination

Freshwater scarcity, exacerbated by environmental pollution, poses a significant global challenge. This study addresses these challenges by developing a Prussian blue/carbonized wood (PB/CW) photothermal composite for solar desalination. The PB/CW composite exhibits enhanced solar absorption and photothermal conversion. The integration of Prussian blue (PB) on the honeycomb structure of wood facilitates efficient water transport and minimizes heat loss, underscoring the composite’s potential in practical solar desalination applications. Under natural sunlight, the PB/CW system achieves an evaporation rate of 4.39 kg m-2 h-1, demonstrating its high efficiency in converting solar energy into water evaporation. This work offers a novel and effective approach to designing low-cost, high-efficiency solar evaporators, advancing the field of sustainable desalination technology.

Responsive integration performed by laser-induced Er3+ structural doping and graphene nanoplatelets

Laser-induced preparation method has the advantages of high efficiency, high yield, no ionic diffusion restriction and competitive side reaction, which can prepare diversified composite materials based on small-scale and distributed characteristics. Besides, integrating multiple performance and conducting inductive feedback are helpful for the reliability and calibration of laser-induced materials in the precision field. Herein, responsive integration is designed based on graphene nanoplatelets/ZnSe:Er3+ composite with optical, electrical, thermal and visual properties for real-time feedback. Er3+ ions doped ZnSe is obtained by fast laser-induced method, combined with two-dimensional graphene nanoplatelets and assembled into temperature-sensitive polyimide and cellulose paper, realizing the characteristics of photoelectric conversion and photothermal conversion. Besides, red fluorescence guiding perceptual behavior can also be produced under the radiation of NIR laser. Based on the proposed composite, bionic flower is constructed, and exhibits good motion features in blooming. Meanwhile, large curvature bending, high thermal sensitivity and strong fluorescence emission are also revealed. Such performance combination design provides a convenient approach for multi signals cross feedback in soft actuator, which strengthens the monitoring and guidance of motion perceptions, and can be potentially applied in diversified fields.

Early Diagnosis of Liver Injury and Real-Time Evaluation of Photothermal Therapy Efficacy with a Viscosity-Responsive NIR-II Smart Molecule.

The early diagnosis of liver injury and in situ real-time monitoring of tumor therapy efficacy are important for the enhancement of personalized precision therapy but remain challenging due to the lack of reliable in vivo visualization tools with integrated diagnostic, therapeutic, and efficacy monitoring functions. Herein, a smart second near-infrared window (NIR-II) molecule (BITX-OH) is rationally designed for diagnosis and therapy by vinyl-bridging hydroxyl diphenyl xanthine unit and benzo[cd]indolium skeleton. BITX-OH exhibits high selectivity and sensitivity toward viscosity, exhibiting a significant enhancement (1167-fold) in NIR-II fluorescence at 962nm. With the assistance of BITX-OH and NIR-II fluorescence imaging, early diagnosis and therapeutic evaluation of non-alcoholic fatty liver (NAFL), as well as in-site real-time monitoring of hepatic fibrosis (HF) in live mice have been successfully achieved, which is at least several hours earlier than the typical clinical test. Notably, BITX-OH displays excellent photothermal conversion efficiency when exposed to an 808nm laser, which can induce tumor ablation and increase viscosity, thereby enhancing NIR-II fluorescence for the real-time evaluation of photothermal therapy (PTT). This viscosity-based "self-monitoring" strategy provides a convenient and reliable platform for timely obtaining therapeutic feedback to avoid over- or under-treatment, thus enabling personalized precision therapy.

Synergistic chemo-photothermal anticancer effect of pH-responsive curcumin loaded mesoporous silica decorated reduced graphene

Synergistic chemo-photothermal therapy is employed to treat cancer. In this work, the curcumin loaded mesoporous silica on reduced graphene oxide (Cur-mSiO2@rGO) is synthesized. The mSiO2@rGO nanocarrier combines rGO to absorb NIR radiations with mSiO2 to load the drug. The mSiO2@rGO thus functions as bimodal photothermal agent and pH-responsive drug nanocarrier. Curcumin loaded onto the nanocarrier possesses antiproliferative, antioxidant, anti-inflammatory, pro-apoptotic, and antiangiogenic characteristics. It has anticancer potential against malignancies of stomach, liver, breast, lungs, and prostate. Breast cancer (BCa) is a major health concern worldwide. Curcumin inhibits BCa by mechanisms including apoptosis, cell cycle arrest, and modulation of signaling pathways. Moreover, curcumin blocks transcription factor (NF-κB), PI3K/AKT signaling, and STAT3 protein to inhibit liver cancer cell growth and survival. Cur-mSiO2@rGO targets cancer cells with enhanced loading capacity of 92 ± 1.02 % curcumin which is specifically released in the acidic tumor environment. NIR lamp irradiation at 808 nm ablates cancer cells to demonstrate the high photothermal conversion efficiency of rGO. In vitro experiments prove that synergistic chemo-photothermal therapy effectively kills cancer cells (HepG2 and MCF-7) compared to the single chemotherapeutic treatment. The toxicity of Cur-mSiO2@rGO is analyzed in vivo by the serum biochemical analysis, and biosafety by histopathological examination of vital body organs. A 1000 mg/kg specific dose of Cur-mSiO2@rGO shows no toxic effect on mice organs. Additionally, the in vivo studies confirm that Cur-mSiO2@rGO with NIR reduces tumor growth. Therefore, the multifunctional Cur-mSiO2@rGO can be a safe chemopreventive nanocarrier in tumor management and cancer photothermal therapy.

Photothermally reinforced chemodynamic therapy in the treatment of osteosarcoma by polydopamine-modified, copper peroxide loaded ZIF8 nanoparticles

Chemodynamic therapy (CDT) has played an important role in osteosarcoma (OS) treatment. However, the insufficient content of endogenous H2O2 and high expression of glutathione (GSH) in tumor tissues limit the antitumor efficacy of CDT. In this work, we developed polydopamine (PDA) coated and CuO2 NPs loaded ZIF8 nanoparticles (CuO2@ZIF8@PDA NPs) for thermally reinforced CDT treatment of OS. The CuO2@ZIF8@PDA NPs exhibited excellent stability in neutral solutions while degraded in weakly acidic environments to generate hydrogen peroxide (H2O2) and Cu2+. Cu2+ consumes GSH in tumor tissues to generate Cu+. Both Cu2+ and Cu+ catalyzed the decomposition of H2O2, triggering a Fenton-like reaction to produce hydroxyl radicals (•OH). The PDA coating endowed the nanosystem with photothermal conversion capabilities under near-infrared laser irradiation, further promoting the generation of •OH, and inducing tumor cell death. In vitro experiments demonstrated that CuO2@ZIF8@PDA NPs exhibited significant toxicity towards K7M2 cells while remaining non-toxic to normal cells. In vivo studies revealed that under 808 nm laser irradiation, CuO2@ZIF8@PDA NPs exhibited stronger killing ability against K7M2 cells than CuO2@ZIF8@PDA NPs alone. This system, which combines GSH depletion, intratumoral H2O2 self-generation, and photothermally enhanced CDT, holds great promise for playing a pivotal role in the treatment of osteosarcoma.

Green synthesis of Au nanoparticles by Scutellaria barbata extract for chemo-photothermal anticancer therapy

IntroductionThe combination of photothermal therapy and chemotherapy has emerged as a promising strategy for cancer treatment. The green synthesis of gold nanoparticles (Au NPs) using extracts from traditional Chinese medicine Scutellaria barbata D. Don (Scu) has revealed an economical, sustainable, and eco-friendly approach for the outstanding anticancer activities. MethodsScu extract was mixed with HAuCl4 solution to fabricate Scu-Au NPs. The synthesis process was optimized by varying the reaction temperature, reaction time, and HAuCl4 concentration. The changes in the components of Scu before and after synthesis were analyzed using the 3,5-dinitrosalicylic acid (DNS) reduction test, the rutin colorimetric method, and the Folin–Ciocalteu method. The morphology, size, and structure of Scu-Au NPs were characterized by TEM, DLS, XRD, and XPS. The photothermal characteristics induced by near-infrared (NIR) irradiation were assessed by continuously monitoring the temperature elevation. The anticancer activity and mechanisms of Scu-Au NPs were investigated using MTT assay, cell uptake studies, ROS level detection, cell apoptosis and necrosis assays, flow cytometry analysis, intracellular Caspase-3 protein activity fluorescence detection, and Western blot analysis on A549, 4T1, and RAW264.7 cells. ResultsScu-Au NPs were successfully fabricated using Scu extract as a reducing agent. The Scu-Au NPs were spherical with a size of 50 nm. During the synthesis process, the levels of reducing sugars, flavonoids, and polyphenols in the Scu extract decreased by 80.8%, 54.3%, and 70.1%, respectively. Scu-Au NPs demonstrated excellent photothermal responsiveness, thermostability, and biocompatibility. For chemo-photothermal anticancer therapy, the cytotoxicity of Scu-Au NPs on 4T1 cells reached approximately 85% upon exposure to 808 nm NIR irradiation. The anticancer activity was attributed to the induction of apoptosis and necrosis, achieved by increasing intracellular ROS levels, causing cell cycle arrest at the S phase, and modulating the expression of apoptosis-related proteins. DiscussionOur synthesized Scu-Au NPs exhibit favorable photothermal conversion characteristics, demonstrating excellent therapeutic efficacy and safety for cancer treatment.

Multifunctional ICG-SB@Lip-ZA Nanosystem Focuses on Remodeling the Inflammatory-Immunosuppressive Microenvironment After Photothermal Therapy to Potentiate Cancer Photothermal Immunotherapy.

Achieving full eradication of residual tumors post photothermal therapy (PTT) hinges on the immune system's activation and response. Nevertheless, the resultant local inflammation attracts a significant influx of aberrant immune cells and fibroblasts, such as tumor-associated macrophages (TAMs) and cancer-associated fibroblasts (CAFs), following tumor PTT. This phenomenon exacerbates immune evasion and the persistence of residual tumor cells, culminating in tumor recurrence and advancement. To tackle this challenge, a combined therapeutic approach utilizing multifunctional ICG-SB@Lip-ZA nanosystem has been introduced. Indocyanine green (ICG) as a photothermal-transducer ablated tumor cells, zoledronic acid (ZA) depletes TAMs recruited by the inflammatory tumor microenvironment (mostly M2-like phenotype), SB-505124 affects CAFs proliferation in the tumor microenvironment (TME) by inhibiting the transforming growth factor-β （TGF-β） pathway, thereby removing physical barriers to T cell infiltration. In a breast cancer model, these immunomodulatory nanoliposomes markedly decrease the population of M2-like TAMs in the TME, eliminate physical barriers hindering T cell infiltration, reshape the inflammatory immune-suppressive tumor microenvironment, eventually leading to a rate of tumor eradication of 94%. This multifunctional ICG-SB@Lip-ZA nanosystem (including photothermal conversion, TAM depletion, and TGF-β pathway blockade) offers a promising strategy for mitigating the deteriorating tumor microenvironment following PTT and presents a more efficient approach for clinical photothermal-immune combination therapy.

Tuning the Fe-Gd nanoparticles co-functionalized mesoporous carbon from sphere to nanobowl for advanced bioapplications

Studies on the function-integrated nanocomposites with well-tuned morphologies have received considerable interest. Here, we reported the preparation of mesoporous carbon nanobowl integrated with stoichiometric γ-Fe2O3 and GdPO4 nanoparticles (Fe-Gd/MCN-B) for morphological advantage exploration. Followed by (i) emulsion-induced interface anisotropic assembly of polydopamine, (ii) solvent evaporation-induced sorption of Wells-Dawson-like heterometallic cluster of {Fe6Gd6P6} and (iii) temperature-programmed carbonization, Fe-Gd/MCN-B with the size around 200 nm was isolated. Our in-vitro studies revealed that Fe-Gd/MCN-B showed a 63.0 % amplified photoacoustic (PA) signal intensity as compared with its nanospherical analogue of Fe-Gd/MCN-S owing to the enhanced light harvesting and photothermal conversion on the interface of its nanobowl morphology. Furthermore, the combined magnetic resonance (MR) imagining, drug delivery and photothermal treatment efficacy in Fe-Gd/MCN-B were also validated in-vitro. These results demonstrated that the delicate design of the morphology of function-integrated nanocomposites is an available way for enhanced imaging performance.

Graphene aerogel with double pore structure for marine oil spill emergency response

Due to its high porosity, large specific surface area, and strong photothermal conversion performance, graphene aerogel has unique advantages in the field of pollution treatment, especially in the field of recovering highly viscous oils. However, for the treatment of highly viscous oils, the high adsorption capacity and high adsorption rate of graphene aerogel often cannot be combined, which is one of the important reasons limiting its development in this field. A double-step templating strategy for graphene aerogels preparation was used in this work, i.e., Pickering emulsion soft templating and unidirectional freeze casting. Specifically, the dense Pickering emulsion droplets can be stabilized in a short period of time, so that they can be cured quickly. After that, graphene aerogels (DGA-0.8-25) with dual pore structure were prepared by unidirectional freeze casting technology to further form aligned pores based on the pores formed by the Pickering emulsion droplet soft template. The dense presence of Pickering emulsion droplets gives DGA-0.8-25 an ultra-high porosity (96.8 %), which can adsorb 184.53 times its own mass of crude oil. Due to the unidirectional pore structure, the adsorption rate of DGA-0.8-25 on crude oil is as high as 8.39 g·g−1·min−1, which realizes dual improvement of the adsorption capacity and rate of graphene aerogel on crude oil and shows a good application prospect in the treatment of high viscosity crude oil. In addition, DGA-0.8-25 has unique advantages in the field of oil–water separation, with a separation efficiency of 99.04 % for water-in-oil emulsions and 97.63 % for oil-in-water emulsions. When repeated used in photothermal adsorption of highly viscous oil, DGA-0.8-25 can still maintain more than 90.61 % of its initial adsorption capacity after ten cycles of use-regeneration. Because of its unique advantages such as high efficiency and low cost, DGA shows promising in its future large-scale use.

A triple-mode strategy combining low-temperature photothermal, photodynamic, and chemodynamic therapies for treating infectious skin wounds.

The skin is the first natural barrier of the human body. Bacterial infections severely hinder the healing process of skin wounds and pose a great threat to human health. Therefore, it is particularly urgent to develop new antimicrobial strategies for bacterial pathogen clearance and wound healing. In this study, a metal-organic framework (MOF), Fe-MIL88B-NH2, was incorporated with the photosensitizer indocyanine green (ICG) to construct composite nanoparticles (MOF@ICG NPs) with multiple antibacterial activities. Under mild near-infrared (NIR) irradiation, the photosensitizer ICG in the MOF@ICG NPs undergoes photothermal conversion (∼45 °C) and photodynamic reactions to generate heat and singlet oxygen (1O2). In addition, the Fenton reaction of the NPs with hydrogen peroxide (H2O2) in the bacterial infection microenvironment resulted in the generation of hydroxyl radicals (˙OH), thus achieving the three-mode combination of low-temperature photothermal therapy (PTT)/photodynamic therapy (PDT)/chemodynamic therapy (CDT). The in vitro experimental results showed that MOF@ICG MPs had excellent antibacterial properties and good cytocompatibility, with some ability to promote the migration of L-929 fibroblasts. Furthermore, under NIR irradiation, MOF@ICG NPs could significantly kill bacteria and promote skin wound healing according to the results of animal experiments. The wound healing rate reached 87.1% after 7 days of treatment. The research results break through the limitations of single-mode antibacterial technology and provide certain theoretical guidance and technical support for the research and development of new antibacterial materials.

Neuron-Inspired Flexible Phase Change Materials for Ambient Energy Harvesting and Respiration Monitoring.

The global energy crisis and climate change pose unprecedented challenges. Wearable devices with personal thermoregulation and energy harvesting hold great promise for achieving energy savings and human thermal comfort. Here, inspired by neurons, a novel phase change material (PCM) is reported for efficient energy harvesting and respiratory monitoring via a self-assembly strategy. The use of gum arabic (GA) enabled the encapsulation of polyethylene glycol (PEG) and the targeted distribution of carboxylated multi-walled carbon nanotubes (cMWCNTs) simultaneously in poly (ethylene vinyl acetate) (EVA) matrix. The material exhibits an outstanding toughness value of 14.88MJ m-3 and high elongation at a break of 565.67%, exhibiting remarkable flexibility. The material with sufficient melting enthalpy (71.11 J g-1) demonstrates high photothermal conversion efficiency (95.27%) under 808nm laser irradiation (105mW cm-2). In addition, due to the synergistic effect of GA and PEG, especially the formation of microdome structures on the surface, the material demonstrates ultrasensitive humidity responsiveness for respiratory monitoring with high precision, excellent repeatability, and fast response/recovery time (50.4/50.5ms). Notably, it shows great potential for moisture-electric generators (MEGs) with the function of non-contact sensing. This material opens the path toward next-generation wearable devices in energy conversion and health monitoring.