Excellent Photothermal Conversion Performance Research Articles

FeOOH Quantum Dots Assembled MXene-Decorated 3D Photothermal Evaporator for Synergy Application in Solar Evaporation and Fenton Degradation.

Solar-driven water evaporation is considered as the sustainable approach to alleviate freshwater resource crisis through direct use of solar energy. However, it is still challenging to achieve the multifunctional solar evaporators equipped with both high evaporation and purification performance to handle practical complex wastewater. Here, a simple and cost-effective multifunctional 3D solar evaporator is prepared by alternately decorating the commercial sponge with FeOOH quantum dots (FQDs) supported MXene sheets composites and chitosan hydrogel coatings for enabling the solar water evaporation and organic wastewater photodegradation simultaneously. MXene composites allow the solar evaporator with excellent photothermal conversion performance, the hydrophilic chitosan hydrogel coated interconnecting skeleton structures of sponge serve as the mass transfer and water transport channels. The Fenton-catalytic FQDs anchored on the MXene sheets surface accept the photo-generated electrons of MXene sheets to induce the organic pollutant photo-Fenton degradation reaction under sunlight irradiation. The resulting evaporator possesses both excellent water evaporation rate of 2.54kg m-2h-1 and high degradation efficiency (99.24% for methylene blue), coupled with durable salt-resisting performance during long-term seawater desalination (20 wt.% NaCl). This work provides a simple and feasible strategy for designing multifunctional solar evaporators to meet the potential application scenarios in practice.

Superhydrophobic, Multifunctional, and Mechanically Durable Carbon Aerogel Composites for High-Performance Underwater Piezoresistive Sensing.

Carbon aerogel piezoresistive sensors (CAPSs), owing to their good thermal stability, self-constructed conductive network, and fast response to pressure, have attracted extensive attention in the field of flexible and wearable electronics in recent years. However, it is still a great challenge for CAPSs to monitor subtle deformations and achieve high-performance underwater piezoresistive sensing. Herein, a superhydrophobic and electrically conductive carbon aerogel composite (CAC) was fabricated by the combination of fluorination of carbon aerogels and decoration of fluorinated halloysite nanotubes (HNTs). Due to the exceptional light absorption and excellent photothermal conversion performance, CAC has a fast and accurate response to temperature with a high-temperature coefficient of resistance (TCR) of -1.06%/°C. The resistance of CAC exhibits a linear response toward compressive strain up to 80% with a high gauge factor of -1.24. Significantly, the CAC sensor can effectively detect tiny deformations, thanks to its excellent waterproof performance, and it enables stable output of sensing signals in an underwater environment. This work provides new insights into the development of superhydrophobic, multifunctional, and mechanically durable piezoresistive sensors with potential applications in underwater flexible electronics.

Dual-emission carbon dots-based biosensor for polarity/targeting bimodal recognition and mild photothermal therapy of tumor

It is essential to develop a multifunctional nanoplatform for biosensing, tumor diagnosis and treatment simultaneously. Herein, dual-emission fluorescent carbon dots (HA-CDs) were fabricated via a one-pot solvothermal method using spinach powder as carbon source and hyaluronic acid (HA) as targeting agent. The obtained HA-CDs exhibited outstanding optical properties, good targeted tumor and excellent photothermal conversion performance. Interestingly, HA-CDs can sensitively perceive the changes in polar environments attributed to the inherent ratiometric fluorescence characteristics, and combined with the intrinsic targeting tumor ability achieved tumor cell recognition. More importantly, the HA-CDs possess good photothermal conversion efficiency of 21.2 % to be beneficial for photothermal therapy of tumors. The survival rate of HeLa cells incubated with HA-CDs dramatically decreased to 14 % after 660 nm laser irradiation, revealing the significant tumor inhibition of HA-CDs in vitro. Notably, through individual intraperitoneal and intratumoral injection, it was found that HA-CDs demonstrated a similar tumor suppressed effect on 4T1 tumor-bearing mice exposed to laser irradiation, fully uncovering that HA-CDs can efficiently accumulate at tumor site by intraperitoneal injection. Besides, the histopathological analysis of major organs ex vivo revealed a good biosafety profile. Collectively, this strategy of designed HA-CDs provides a new multifunctional nanoplatform for potential clinical application.

Bifunctional Photothermal Evaporator Based on an MXene/Fe-MOF Collaborative Effect toward Efficient Solar Steam Generation and Simultaneous VOC Removal.

Solar-driven interfacial water evaporation has become one of the most promising approaches to effectively harvesting freshwater, yet the fabrication of high-performance and multifunctional solar interfacial evaporators (SIEs) still remains a huge challenge to date. In this study, a multifunctional MXene and Fe-MOF@cellulose acetate/polyvinylpyrrolidone (MXM@CP) SIE was prepared via a facile "electrospinning and suction filtration deposition" coupling strategy. Thanks to the incorporation of MXene, MXM@CP displayed excellent photothermal conversion performance. Together with the fast water transport channel provided by the porous cellulose acetate electrospinning substrate, a remarkable solar-driven water evaporation property was achieved for MXM@CP, showing a higher water evaporation rate of 1.1 kg m-2 h-1 under one sun irradiation. Moreover, the resultant composite film also exhibited excellent Fenton catalytic activity to effectively degrade volatile organic compounds (VOCs) due to the synergistic effect of the MXene and Fe-based MOF (Fe-MOF). Particularly, a relatively higher degradation rate of 82.8% was acquired for the resulting evaporator toward the benzene contaminant. These results provide new insights into the construction of high-performance and multifunctional SIEs toward clean freshwater collection from the VOC-contaminated water system.

Fabrication of Low-Cost Porous Carbon Polypropylene Composite Sheets with High Photothermal Conversion Performance for Solar Steam Generation.

The development of absorber materials with strong light absorption properties and low-cost fabrication processes is highly significant for the application of photothermal conversion technology. In this work, a mixed powder consisting of NaCl, polypropylene (PP), and scale-like carbon flakes was ultrasonically pressed into sheets, and the NaCl was then removed by salt dissolution to obtain porous carbon polypropylene composite sheets (P-CPCS). This process is simple, green, and suitable for the low-cost, large-area fabrication of P-CPCS. P-CPCS has a well-distributed porous structure containing internal and external connected water paths. Under the dual effects of the carbon flakes and porous structure, P-CPCS shows excellent photothermal conversion performance in a broad wavelength range. P-CPCS-40 achieves a high temperature of 128 °C and a rapid heating rate of 12.4 °C/s under laser irradiation (808 nm wavelength, 1.2 W/cm2 power). When utilized for solar steam generation under 1 sun irradiation, P-CPCS-40 achieves 98.2% evaporation efficiency and a 1.81 kg m-2 h-1 evaporation rate. This performance means that P-CPCS-40 outperforms most other previously reported absorbers in terms of evaporation efficiency. The combination of carbon flakes, which provide a photothermal effect, and a porous polymer structure, which provides light-capturing properties, opens up a new strategy for desalination, sewage treatment, and other related fields.

Tumor Microenvironment-Responsive Biodegradable Nanomedicine for Self-Enhanced Synergistic Chemo-, Photothermal, and Chemodynamic Therapy.

The nanoscale multidrug codelivery system for synergistic therapy is an effective strategy for tumor treatment. However, the low drug delivery efficiency and poor therapeutic effects limit its application. Here, based on the coordination effect of Artemisinin (Art), quercetin (Qc), and Fe3+, we had constructed a safe and efficient carrier-free hyaluronic acid (HA)-modified Art-Fe-Qc nanoparticles (AFQ@HA NPs) for enhanced chemotherapy/photothermal therapy (PTT)-chemodynamic therapy (CDT) synergistic therapy, which achieved an ultrahigh drug loading efficiency and a multifunction anticancer strategy. The results showed that high drug loading was achieved based on drug coordination self-assembly, with Art and Qc contents of 38.6 and 42.7%, respectively. At the same time, based on the Qc-Fe coordination molecular network, the system had excellent photothermal conversion performance with an efficiency of 57.3% and could effectively inhibit the expression of HSP70, achieving enhanced PTT. Further, under the stimulation of excessive H2O2 and glutathione (GSH) in the tumor microenvironment, the AFQ@HA NPs were continuously degraded, while releasing Art and Fe3+/Fe2+ to achieve iron ion-enhanced CDT. The results of in vitro and in vivo experiments showed that AFQ@HA NPs could achieve chemotherapy-PTT-CDT synergistic therapy in response to tumor microenvironment by passively targeting and actively targeting tumor cells with CD44, demonstrating its excellent targeted antitumor effects.

Nanofiber aerogel with layered array with structure coupled photothermal/magnetothermal effect for continuous seawater desalination

The solar evaporation is susceptible to intermittent solar irradiation as well as salt crystallization deposition on the surface severely limits the evaporation efficiency. In this work, subject to inspiration of the transpiration, groove array structure and antifouling performance of banana leaves, a multifunctional photothermal/ magnetothermal coupled three-dimensional(3D) aerogel evaporator with layer-by-layer array structure was prepared by blow-spun technology which can achieve mass produced. The unique super hydrophilic vertical array structure has multi-scale high-efficiency water transport channels and the SnSe-Fe3O4 evaporation layer realizes super hydrophobic self-cleaning and excellent photothermal and magnetothermal conversion performance, which can achieve all-weather seawater desalination. The vertical array structures facilitate the reflection and refraction of light and promote the seawater convection and salt crystals absorption coupling. It could improve the photothermal conversion efficiency and salt resistance of the evaporator. Which resulted in an evaporation rate of 2.53 kg m−2h−1 under 1 sun, with solar energy conversion efficiency of 105 % and the evaporation rate is about 4.54 kg m−2h−1 at a magnetic field. Furthermore, it could purify organic pollutants in industrial wastewater and use waste heat to generate electricity. This evaporator provides a new economical and environmentally friendly solution for seawater desalination and sewage treatment.

Fabrication of boron nitride/copper oxide@multi-walled carbon nanotubes composites for enhancing heat transfer and photothermal conversion of phase change materials

To realize the efficient storage and conversion of solar energy by phase change materials (PCMs), low photothermal conversion efficiency and poor heat transfer performance remain great challenges. Herein, polyethylene glycol (PEG)-based composite PCMs with excellent photothermal conversion performance and exceptional thermal management capability were obtained by using boron nitride/copper oxide@multi-walled carbon nanotubes (BN/CuO@MWCNTs) as the thermal conductive and photothermal conversion enhancement fillers. The results indicate that owing to the bridging effect, the introduction of CuO and MWCNTs on the BN surface can construct additional heat transfer paths, resulting in a high thermal conductivity of up to 2.35 W/(m·K) for the as-prepared PEG/BN/CuO@MWCNTs composite, which is about 9-folds enhancement than pristine PEG. Simultaneously, the supercooling degree of PEG in PEG/BN/CuO@MWCNTs is effectively suppressed due to the synergistic nucleation effect of BN, CuO and MWCNTs. Additionally, the PEG/BN/CuO@MWCNTs composites not only exhibit a high latent-heat capacity of 154.5 J/g and a high photothermal conversion efficiency of 92.2 %, but also show favorable shape stability and durable reliability. This work offers a workable solution for the synergistic enhancement of photothermal conversion and thermal management, which can effectively promote the practical application in solar energy conversion and storage.

Plant transpiration inspired biomass-derived solar evaporator for highly efficient solar vapor generation

The interface solar evaporation is an energy-saving and environmentally friendly method for seawater desalination and sewage purification. In this work, a biomimetic solar evaporator (ppy@AZL) inspired by plant transpiration was designed to achieve high efficient vapor generation. The ppy@AZL evaporator was made of zizania latifolia as raw material, has a cellulose skeleton with high water transport after alkalization and was decorated with photothermal polypyrrole to form bionic branches and leaves, and has excellent photothermal conversion performance. The evaporation performance and potential application of ppy@AZL evaporator in seawater desalination and sewage treatment were studied. The results indicated that the average evaporation rate of the ppy@AZL in simulated seawater (3.5 wt%) under the irradiation of one sun (1 kW m−2) was 2.239 kg m−2 h−1, and the photothermal conversion efficiency was 93.4 % in this work. In addition, the ppy@AZL evaporator has excellent evaporation rate of 2.668 kg m−2 h−1 in 9 h outdoor continuous evaporation experiment of simulated seawater (3.5 wt%), and can continuously and stably generate vapor. Therefore, this study provided a new solar evaporator with low-cost, simple preparation, better salt resistance, and high evaporation performance for seawater desalination and sewage treatment.

Silk Fabrics Modified with Photothermal Phase Change Microcapsules for Personal Thermal Management.

With the development of technology, personal heat management has become a focus of attention. Phase change fabrics, as intelligent materials, are expected to be widely used in multiple fields, bringing comfortable, intelligent and convenient living experience. In this study, miniature phase change microcapsules (MPCM) with n-octadecane as core and poly(methyl methacrylate) as shell were successfully prepared. Using the in-situ reduction property of polydopamine, gold nanoparticles were deposited on the surface of the microcapsules, which retained the heat storage function and imparted photothermal and antibacterial properties. The MPCM with photothermal conversion function was modified on the surface of silk fabric using aqueous polyurethane after verified by comprehensive material characterisation techniques. Under the near infrared light of 808 nm wavelength and 0.134 W/cm² irradiation intensity, the MPCM@PDA@Au modified silk fabrics showed excellent photothermal conversion performance, which could be increased from 25°C to 60°C in 50s. After the light source was cut off, the fabrics showed good heat release ability, with melting enthalpy and crystallisation enthalpy reaching 41.58 J/g and 43.3 J/g, respectively, which were not changed after repeated cycles. After the light source is cut off, the fabric has good heat release ability, and the enthalpy of melting and crystallisation reaches 41.58 J/g and 43.3 J/g, respectively, and the photothermal efficiency remains unchanged after many cycles of use, which proves that it has excellent durability and stability. The antimicrobial test shows that the fabric has significant antibacterial effect on Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). MPCM@PDA@Au silk fabrics bring new possibilities for the future of personal thermal management and antimicrobial protection in the field of medical health, outdoor sports and other areas of broad application prospects, heralding the birth of a series of innovative applications and solutions.

Insight into the photothermal boosted ofloxacin removal by magnetic CuFe2O4/pyrite waste catalyst: Mechanism, degradation pathways, and toxicity evaluation

The widespread distribution of antibiotics in natural waters has raised global concerns due to their potential threat to the aquatic environment. In this study, 40 %-CuFe2O4/pyrite waste composite material was constructed for the removal of ofloxacin (OFX) through activating H2O2 in photothermal Fenton processes. It had excellent photothermal conversion performance and could serve as a superior photothermal-Fenton catalyst. The removal efficiency of OFX was 96.13 % in the photothermal Fenton reaction, and the apparent first-order kinetics rate constant (k) was 4.33 and 12.15 times higher than in the traditional Fenton without light and 40 %-Fe/PW photothermal Fenton reaction. This could be attributed to the introduction of photothermal effect promoted collisions between substances, and expedited the reaction rate. The redox cycle of Fe(II)/Fe(III) and Cu(I)/Cu(II) in the Cu-Fe bimetal system also contributed to the removal of OFX. Besides, it exhibited excellent cycling stability, extensive adaptability for various pollutants and water properties. The order of contribution of active radicals to the removal of OFX was ∙ OH>h+ >∙O2-, and they attacked the active atoms of OFX molecule with high Fukui index. Hopefully, this study may encourage the utilization of the photothermal effect for contaminant removal and introduce a novel perspective for environmental remediation.

Ultrasensitive electrospinning fibrous strain sensor with synergistic conductive network for human motion monitoring and human-computer interaction

With the rapid development of wearable electronic skin technology, flexible strain sensors have shown great application prospects in the fields of human motion and physiological signal detection, medical diagnostics, and human-computer interaction owing to their outstanding sensing performance. This paper reports a strain sensor with synergistic conductive network, consisting of stable carbon nanotube dispersion (CNT) layer and brittle MXene layer by dip-coating and electrostatic self-assembly method, and breathable three-dimensional (3D) flexible substrate of thermoplastic polyurethane (TPU) fibrous membrane prepared through electrospinning technology. The MXene/CNT@PDA-TPU (MC@p-TPU) flexible strain sensor had excellent air permeability, wide operating range (0–450 %), high sensitivity (Gauge Factor, GFmax = 8089.7), ultra-low detection limit (0.05 %), rapid response and recovery times (40 ms/60 ms), and excellent cycle stability and durability (10,000 cycles). Given its superior strain sensing capabilities, this sensor can be applied in physiological signals detection, human motion pattern recognition, and driving exoskeleton robots. In addition, MC@p-TPU fibrous membrane also exhibited excellent photothermal conversion performance and can be used as a wearable photo-heater, which has far-reaching application potential in the photothermal therapy of human joint diseases.

Eco-friendly superhydrophobic sponges for efficient oil-water separation and resource recycling

Owing to the risk of oil spills in the water pollution and human health, it is urgent to exploit the efficient, simple and low-cost materials to treat oily wastewater. Inspired by the native super-wettability surface of lotus leaves, a green, multi-functionality, multi-response and recyclable superhydrophobic material has been established via an one-step dip-coating method based on waste polyurethane sponges (PU), which is expected to settle the treatment problem of oil/water mixture. And the coating system is mainly constituted by a mixture of silicon resin, nano-Fe3O4 and ultrafine expandable graphene (EG), which can act as lowing low surface energy and fabricating the hierarchical micro-/nano-scaled surface roughness. The water contact angle (WCA) of 156.2 ± 1.4° and water sliding angle (WSA) of 8.0 ± 0.5° have triggered a series of skills in water repellency, self-cleaning and anti-fouling. Most of all, the exceptional oil–water separation capabilities have been achieved that the sorption capacity, separation efficiency and flux for light oil can reach 33.2 g/g, 99.5 % and 31,611 L m-1h−1, respectively. Accorded with the intrinsic thermal harvesting ability of Fe3O4 and EG, the excellent photothermal conversion performance has been gained that the temperature of superhydrophobic sponges can reach 68.7 °C in 180 s when the irradiation intensity is 1.2 sunlight, endowing the potential sorption ability of high-viscosity crude oils. Most importantly, the various oil–water separation modes can be also realized that are composed of gravity-driven, magnetism-driven, vacuum-driven and photothermal-driven methods. Except that, the adequate flame retardancy, mechanical durability and chemical stability have been acquired that have raised the high-value-added utilization of modified sponges in fields of environment protection and functional materials.

NIR-responsive CN-Pt-GEM hydrogel induces necroptosis and immunotherapeutic responses prevent postoperative recurrence and wound infection in lung carcinoma

BackgroundCancer recurrence following surgical resection is a major cause of treatment failure. Finding effective methods to prevent postoperative recurrence and wound infection is an important component of successful surgery. With the development of new nanotechnology, more treatment options have been provided for postoperative adjuvant therapy. This study presents an innovative hydrogel system that stimulates tumoricidal immunity after surgical resection of non-small cell lung cancer (NSCLC) and prevents cancer relapse.ResultsThe hydrogel system is based on the excellent photothermal conversion performance of single-atom platinum (CN-Pt) along with the delivery and release of the chemotherapy drug, gemcitabine (GEM). The system is coated onto the wound surface after tumor removal with subsequent near-infrared (NIR) photothermal therapy, which efficiently induces necroptosis of residual cancer cells, amplifies the levels of damage-associated molecular patterns (DAMPs), and increases the number of M1 macrophages. The significantly higher levels of phagocytic macrophages enhance tumor immunogenicity and sensitize cancer cells to CD8 + T-cell immunity to control postoperative recurrence, which has been verified using an animal model of postoperative lung cancer recurrence. The CN-Pt-GEM-hydrogel with NIR can also inhibit postoperative wound infection.ConclusionsThese findings introduce an alternative strategy for supplementing antitumor immunity in patients undergoing resection of NSCLC tumors. The CN-Pt-GEM-hydrogel with the NIR system also exhibits good biosafety and may be adaptable for clinical application in relation to tumor resection surgery, wound tissue filling, infection prevention, and recurrence prevention.

Self-assembled Au-CQDs nanofluids with excellent solar absorption and medium–high temperature stability for solar energy harvesting

Nanofluids-based direct absorption solar collectors are promising candidates for medium–high-temperature solar energy harvesting. However, nanofluids’ complicated preparation process and undesirable high-temperature stability have hindered their practical applications. Herein, we propose a facile method for synthesizing gold/carbon quantum dots (Au-CQDs) nanofluids by directly carbonizing the base fluid and spontaneously assembling with Au nanoparticles (AuNPs) triggered by high temperatures. The results indicate that the self-assembled Au-CQDs nanofluids can maintain high stability at 110 °C for 100 h without precipitation and keep excellent photothermal conversion performance under 10 sun irradiation. The concentration and particle size of AuNPs are crucial factors affecting the self-assembly process. By modulating the microscopic morphologies of the self-assembled nanoparticles, the extinction coefficient of the prepared nanofluids is up to 88.7 % at a low loading of 30 ppm. The nanofluids can reach an equilibrium temperature of 50 °C under 1 sun irradiation, 10.4 °C higher than the base fluid due to the enhanced plasmonic effects and stability resulting from the CQDs dotted AuNPs. This work offers a new strategy to fabricate highly stable nanofluids with excellent light absorption properties for efficient solar thermal applications.

Multifunctional wood-derived cellulose/Ti3C2Tx composite films enhanced by densification strategy for electromagnetic shielding, Joule/solar heating, and thermal camouflage

In the era of increasing reliance on electronic devices, the development of flexible smart composite films that offer multifunctional capabilities such as electromagnetic shielding, sensing, infrared stealth, and autonomous heating is becoming increasingly significant. In this study, we fabricated polydopamine-modified cellulose scaffold/MXene composite films (PCM) using a densification strategy, resulting in films with a thickness of only 33 μm, outstanding tensile strength of 235.28 MPa, and excellent electromagnetic shielding effectiveness of 44.6 dB. The PCM also demonstrates remarkable electrothermal performance, reaching temperatures of up to 610 °C at 5 V, and exhibits excellent photo-thermal conversion performance, along with good cycling stability and tunability. Additionally, the PCM’s low infrared emissivity provides it with exceptional infrared stealth capabilities, effectively concealing a high surface temperature ranging from 250 °C to 25 °C. The PCM’s ability to detect human body movement and light-driven actuation for bionic motions underscores its flexibility and utility as a sensor. Therefore, this efficient and versatile approach provides a promising method for synthesizing multifunctional MXene-based composite films, achieving satisfactory mechanical properties, high electromagnetic interference shielding, and effective thermal management for wearable smart devices and military applications.

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

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

Zwitterion-Modified MXene Quantum Dot as a Nanocarrier for Traditional Chinese Medicine Sanguinarine Delivery and Its Application for Photothermal-Chemotherapy Synergistic Antibacterial and Wound Healing.

The nanomaterialization of traditional Chinese medicine (TCM) has aroused widespread interest among researchers. Sanguinarine (SAN) is a kind of TCM with good antibacterial properties, which has important applications in anti-infection of wounds. Additionally, the combination of photothermal therapy and chemotherapy can overcome bacterial resistance, further improving bactericidal and wound healing efficiency. In this paper, we prepared an antibacterial agent by loading SAN on the zwitterion-modified MXene quantum dot nanocarrier (SAN@AHEP@Ta4C3), realizing pH/NIR controlled drug release and photothermal/chemotherapy synergistic antibacterial and wound healing. The particle size of SAN@AHEP@Ta4C3 is about 120 nm, and it has a good water solubility and stability. In addition, it also has excellent photothermal conversion performance (η = 39.2%), which can effectively convert light energy into heat energy under near-infrared (NIR) laser irradiation, further promoting drug release and achieving bactericidal effects by synergistic chemotherapy and photothermal therapy. The in vitro and in vivo experiments show that SAN@AHEP@Ta4C3 exhibits an excellent antibacterial effect against Staphylococcus aureus and Escherichia coli, and it can effectively promote the wound healing of mice. Moreover, the SAN@AHEP@Ta4C3 also has good biocompatibility and has no side effects on normal tissue and organs. This work introduces a multifunctional antibacterial agent based on TCM and hot-spot material MXene, which will have considerable application prospects in biomedical fields.

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

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

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

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