Photothermal Conversion Properties Research Articles

Liquid exfoliation of molybdenum metallenes for non-inflammatory photothermal therapy of tumors.

Tissue damage and cell death occurring during photothermal therapy (PTT) for tumors can induce an inflammatory response that is detrimental to tumor therapy. Herein, ultrathin Mo metallene nanosheets with a thickness of <5 nm prepared by liquid phase exfoliation were explored as functional hyperthermia agents for non-inflammatory ablation of tumors. The obtained Mo metallene nanosheets exhibited good photothermal conversion properties and significant reactive oxygen species (ROS) scavenging ability, thus achieving superior cancer cell ablation and anti-inflammatory effects in vitro. For in vivo experiments, 4T1 tumors were ablated while the inflammation-related cytokine levels did not obviously increase, demonstrating that the inflammatory response induced by PTT was inhibited by the anti-inflammatory properties of Mo metallene nanosheets. Moreover, Mo metallene nanosheets depicted good dispersibility and biocompatibility, beneficial for biomedical applications. This work introduces Mo metallenes as promising hyperthermia agents for non-inflammatory PTT of tumors.

Metal-polyphenol coordination nanosheets with synergistic peroxidase-like and photothermal properties for efficient antibacterial treatment

Bacterial infections pose a serious threat to human health and socioeconomics worldwide. In the post-antibiotic era, the development of novel antimicrobial agents remains a challenge. Polyphenols are natural compounds with a variety of biological activities such as intrinsic antimicrobial activity and antioxidant properties. Metal-polyphenol obtained by chelation of polyphenol ligands with metal ions not only possesses efficient antimicrobial activity but also excellent biocompatibility, which has great potential for application in biomedical and food packaging fields. Herein, we developed metal-polyphenol coordination nanosheets named copper oxidized tannic acid quinone (CuTAQ) possessing efficient antibacterial and anti-biofilm effects, which was synthesized by a facile one-pot method. The synthesis was achieved by chelation of partially oxidized tannic acid (TA) with Cu2+ under mild conditions, which supports low-cost and large-scale production. It was demonstrated that CuTAQ exhibited high antibacterial activity via disrupting the integrity of bacterial cell membranes, inducing oxidative stress, and interfering with metabolism. In addition, CuTAQ exhibits excellent peroxidase catalytic activity and photothermal conversion properties, which play a significant role in enhancing its bactericidal and biofilm scavenging abilities. This study provides insights for rational design of innovative metal-polyphenol nanomaterials with efficient antimicrobial properties.

Comparative experimental study on photothermal conversion and shape memory properties of MF-based flexible composite phase change materials loaded with carbon nanotubes and polydopamine

Efficient use of solar energy can effectively alleviate the problem of energy shortages. Currently, extensive researches have been carried out on photothermal conversion materials. However, factors such as photothermal conversion and thermal conductivity limit the practical implementation of photothermal materials. In this research, a novel flexible composite phase change material (CPCM) with melamine foam (MF) as the supporting skeleton, carbon nanotube (MWCNT)/polydopamine (PDA) as the light-absorbing coating and polyethylene glycol (PEG) as the energy storage material was successfully prepared. The results show that the MF-based CPCMs have good shape stability with a leakage of only 0.9 %, and high phase change enthalpies, the melting enthalpy was above 172.0 J/g. In addition, the thermal conductivity was improved due to the introduction of light-absorbing coatings into the CPCMs. Compared with MF/PEG, MWCNT/MF/PEG, and PDA/MF/PEG, MWCNT/PDA/MF/PEG were improved by 35.21 %, 8.6 % and 29.46 %, respectively. Finally, the average charging efficiency of MWCNT/PDA/MF/PEG is 96.26 %, which is 62.33 % and 20.1 % higher than that of MWCNT/MF/PEG and PDA/MF/PEG respectively, indicating that MWCNT and PDA nanofillers played a synergistic role in enhancing the performance of CPCMs. This study provides new and innovative ways for the design of photothermal materials.

Ti3C2Tx MXene-assisted solar-driven CO2 adsorption and photothermal regeneration over mesoporous SiO2

Due to the high energy consumption associated with regenerating adsorbents with high carbon dioxide adsorption capacity, utilizing renewable solar energy as an alternative to traditional thermal energy for photothermally regenerating adsorbents is a feasible approach. In this research, a solar-induced regeneration technique has been formulated, employing fumed silica as the framework, MXene as the photothermal conversion component, and (3-aminopropyl)triethoxysilane (APTES) as the site for carbon dioxide adsorption. The findings suggest that incorporating MXene can substantially enhance the photoresponsive and photothermal conversion properties of aminosilica. Beneath an brightening concentrated of 1 kW·m−2, aminosilica@MXene(7 wt%) reaches a maximum temperature of 76.8 °C, compared to only 53.4 °C when using aminosilica alone. Notably, aminosilica@MXene (7 wt%) achieves complete desorption at an illumination intensity of 2 kW·m−2. Through multiple cycling tests, aminosilica@MXene (7 wt%) demonstrates outstanding recyclability. As a result, using solar energy to power the adsorbent photothermal regeneration turns into a useful strategy for lowering the energy required for regeneration.

Rich oxygen vacancies mediated metal-insulator transition materials toward ultrasensitive sensing and energy conversion

Regulating structural phase transitions of metal insulator transition (MIT) correlated materials is an ideal approach to modulate their properties. However, due to phase transition hysteresis, ultrasensitive electron transition is difficult to achieve. Here, we develop a convenient method via Fe ions surface doping-induced oxygen vacancies (OVs) at the Ti3O5 surface to enable ultrasensitive electronic transitions. The Fe doping promotes the formation of free electrons, which is attributed to the reduced bandwidth, making it relatively easy for valence band electrons to leap to the conduction band. The formation of OVs increase the electron concentration and enhance the electronic conductivity (2.49×10−4 S/cm) at low temperatures, resulting in an ultrasensitive sensing over a wide temperature range before metal insulator transition. This unique property facilitates its application in fire warning with ultrasensitive sensing (response time 0.63 s, and response temperature 150 °C) and good durability. Moreover, the as-obtained MIT correlated material with rich-OVs structure exhibits excellent oxygen sensing and photothermal conversion properties. These results offer a novel design for MIT correlated materials and provide an innovative insight for modulating their multifunctional properties.

Deep eutectic supramolecular polymer functionalized MXene for enhancing mechanical properties, photothermal conversion, and bacterial inactivation of cellulose textiles

Two-dimensional (2D) transition metal carbides (Ti3C2Tx MXene) have gained significant attention for their potential in constructing diverse functional materials, However, MXene is easily oxidized and weakly bound to the cellulose matrix, which pose challenges in developing MXene-decorated non-woven fabric with strong bonding and stable thermal management properties. Herein, we successfully prepared deep eutectic supramolecular polymer (DESP) functionalized MXene to address these issues. MXene can be wrapped with DESP to be insulated from water and protected from being oxidized. Subsequently, we achieved an efficient in-situ deposition of DESP-functionalized MXene onto fibers through a combination of dip coating and photopolymerization technique. The resulting nonwoven fabric (CNs-DESP@M) exhibited excellent photothermal conversion properties along with rapid thermal response and functional stability. Interestingly, the interface bonding between MXene and the fiber surface was significantly enhanced due to the abundant pyrogallol groups in DESP, resulting in the composite textile exhibiting commendable mechanical properties (2.68 MPa). Moreover, the as-prepared textile demonstrates outstanding bactericidal efficacy against both Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The multifunctional textile, created through a facile and efficient approach, demonstrates remarkable potential for applications in smart textiles, catering to the diverse needs of individuals in the future.

Versatile superhydrophobic magnetic biomass aerogel for oil/water separation and removal of multi-class emerging pollutants

Water resources contamination by both oil and microplastics (MPs) stands as a pressing environmental concern. To tackle this challenge, we have devised a superhydrophobic magnetic biomass aerogel, synthesized from PDMS-modified carbonized ZIF-67/chitosan (PDMS@CZIF-67/CS). This aerogel exhibits remarkable proficiency in effecting oil/water separation and adsorbing a wide range of emerging pollutants, owing to its inherent superhydrophobicity, stability, and self-cleaning capabilities. Furthermore, the aerogel demonstrates efficient absorption of viscous oils and facilitates self-driven oil absorption through the synergistic photothermal conversion and magnetic properties of CZIF-67, respectively. Following ten consecutive separation cycles, the aerogel consistently upholds its efficacy in oil/water separation, regardless of the employed method, be it gravity-driven or facilitated by a peristaltic pump. Notably, the PDMS@CZIF-67/CS aerogel manifests a high adsorption capacity for various emerging pollutants, specifically MPs, achieving an almost complete adsorption efficiency. This paper introduces an innovative, eco-friendly approach aimed at mitigating oil-contaminated wastewater and emerging pollutants, highlighting its potential for widespread application.

Optimizing cleanup of highly viscous oil spills: A biomass‐based aerogel with photothermal conversion and joule heating for a dual‐energy absorption device

AbstractThe frequent occurrences of offshore oil spills have led to severe environmental contamination and ecological threats. However, traditional recovery methods pose issues such as high‐energy consumption, low absorption efficiency and secondary pollution. This work prepared a hydrophobic aerogel (P‐GO@CNTs‐9/ATP/SA) using sodium alginate, attapulgite and graphene oxide surface‐modified carbon nanotubes with superior solar/Joule heating ability. The water contact angle of this aerogel is approximately 147.5°. Moreover, this aerogel demonstrates stable and efficient photothermal conversion properties, reaching a surface temperature of 82.3 °C under one solar illumination (1 kW/m2). Furthermore, when applying a voltage of 10 V, the surface temperature of the P‐GO@CNTs‐9/ATP/SA aerogel reaches 170.4 °C, assisting photothermal conversion to enhance the fluidity of viscous oil, thereby conserving energy. Finally, we present a continuous absorption device utilizing P‐GO@CNTs‐9/ATP/SA as the primary component, enabling automatic switching between photothermal and electrothermal modes for the comprehensive and continuous treatment of oil spills. Due to the unique design, environmental friendliness and ideal absorption capacity, this approach offers a novel choice for recovery of oil spills, which is expected to further promote principles of sustainable development.

Metal-polyphenol based phase change microcapsules for photothermal conversion and storage

In this paper, a novel phase change microcapsules (MPN@PA) with metal-polyphenol (MPN) as shell material and paraffin (PA) as core material were prepared by interfacial self-assembly method. It has low preparation cost and shows excellent photothermal conversion and heat storage properties. The highest encapsulation rate of MPN@PA without leakage is 59.58% when the shell-core ration is 1.0:1.5. The morphology of MPN@PA is quasi-spheroid with the size of about 10∼26 μm. FT-IR and XRD analysis results show that MPN and PA are combined by hydrogen bonding, and no new substance is formed. The enthalpy of phase transformation of MPN@PA (1.0:1.5) is 140.9 J/g. Moreover, MPN@PA has excellent thermal stability, thermal reliability, photothermal conversion and heat storage efficiency (71.47%–73.31%). The prepared novel photothermal transformation microcapsule is expected to be applied to the high-efficiency storage, management and utilization of solar energy.

Solar-driven, highly-efficient, and environmentally-friendly oil spill cleanup by a superelastic photothermal thermoplastic polyurethane monolith with aligned channels

Cleanup of crude oil spills is challenging due to its high viscosity. Reducing the viscosity of crude oil by elevating its temperature and thus promoting absorption is considered a promising and environmentally-friendly way to address this worldwide issue. Herein, we propose a photothermal superelastic thermoplastic polyurethane (TPU)-based monolith with aligned channels successively modified with MXene and polydimethysiloxane (PDMS) (P-MXene@TPU) for crude oil absorption and recovery. The well-oriented structures help reduce mass transfer hindrance and accelerate heat transfer, while MXene and PDMS endow the monolith with excellent photothermal conversion property and hydrophobicity, respectively. P-MXene@TPU monolith demonstrates superior oil absorption performance under solar irradiation as self-heating is realized to decrease the crude oil viscosity and promote its absorption rate. Particularly noteworthy is that P-MXene@TPU monolith can bear 300 compression cycles with a deformation of 9 % owing to the superelastic TPU skeleton and aligned channels. The stable compression performance and anti-fatigue property validate that the monolith is suitable for recovering crude oil by extrusion. Continuous crude oil recovery is achieved via a pumping device and solar irradiation (1.0 kW/m2) enhances the recovery rate by a factor of 18, as compared to the one without irradiation. Given the unique structural design and exceptional properties, this monolith provides a highly efficient approach for handing the crude oil spills.

Superhydrophobic Co-MOF-based sponge for efficient oil-water separation utilizing photothermal effect

Effectively addressing crude oil spills remains a global challenge due to its high viscosity and limited flow characteristics. In this study, we successfully prepared a modified sponge (PCP@MS) by embedding the photothermal material of Co-HHTP and coating the melamine sponge (MS) with low-surface-energy polydimethylsiloxane (PDMS). The PCP@MS exhibited outstanding hydrophobicity with WCA of 160.2° and high oil absorption capacity of 59–107 g/g. The PCP@MS showed high separation efficiency of 99.2% for various oil-water mixtures, along with notable self-cleaning properties and mechanical stability. The internal micro-nano hierarchical structure on the sponge surface significantly enhanced light absorption, synergizing with the photo-thermal conversion properties of Co-HHTP, enabled PCP@MS to achieve a surface temperature of 109.2 °C under 1.0 solar light within 300 s. With the aid of solar radiation, PCP@MS is able to heat up quickly and successfully lowering the viscosity of the surrounding crude oil, resulting in an oil recovery rate of 8.76 g/min. Density functional theory (DFT) calculation results revealed that Co-HHTP featured a zero-gap band structure, rendering advantageous electronic properties for full-wavelength light absorption. This in situ solar-heated absorbent design is poised to advance the practical application of viscous oil spill cleanup and recovery.

The regulation of CuSNPs' interface for further enhancing mechanical and photothermal conversion properties of chitosan/@CuSNPs hybrid fibers

Our previous study has demonstrated that the microstructure of copper sulfide nanoparticles (CuSNPs) can be controlled to enhance mechanical and photothermal conversion properties of chitosan (CS)/CuSNPs hybrid fibers. However, achieving optimal dispersion and compatibility of CuSNPs within a CS matrix remains a challenge, this study aims to improve dispersion and compatibility by modifying the CuSNPs' interface, thereby enhancing mechanical and photothermal conversion properties of hybrid fibers. The interfaces of @CuSNPs (CuS@Xylan NPs, CuS@SA NPs, and CuS@PEG NPs) contain hydroxyl groups, facilitating the hydrogen bonds formation with the CS matrix. The dispersibility is further enhanced by the synergistic effect of xylan and SA's anionic charges with cationic chitosan. Notably, the viscosity of the CS/@CuSNPs hybrid spinning solution is significantly enhanced, resulting in improved breaking strength for initial hybrid fibers. Specifically, the breaking strength of CS/CuS@Xylan NPs hybrid fibers reaches 1.4 cN/dtex, exhibiting a 42.86 % and 20.6 % increase over CS and CS/CuSNPs hybrid fibers. Simultaneously, the CS/CuS@Xylan NPs hybrid fibers exhibit exceptional photothermal conversion performance, surpassing that of CS fibers by 5.2 times and CS/CuSNPs hybrid fibers by 1.4 times. The regulation of interface modification is an efficient approach to enhance the tensile strength and photothermal conversion properties of CS/CuSNPs hybrid fibers.

Nano-Fe3O4/chitosan-based superhydrophobic coatings with magnetic oil-water separation and photothermal conversion properties

Superhydrophobic coatings are ideal for industrial applications involving oil spill cleaning, de-icing, anti-fouling, and anti-icing. The majority of current superhydrophobic coating preparation techniques have significant costs and pollute the environment, which are incompatible with the principles of sustainable green development. In this study, we produced a superhydrophobic coating based on the low-cost green material chitosan, Fe3O4 nanoparticles, and octadecylamine, which possesses photothermal characteristics and magnetic oil-water separation properties. Among these, octadecylamine supplied a lower surface energy and nano-Fe3O4 supplied the coating's surface roughness structure. Under simulated sunlight, the fabricated coatings produced a pronounced photothermal effect. The surface temperatures of the polyurethane sponge coating and the cotton fabric coating rose to 144.6 °C and 117.5 °C, respectively, after just 5 min. Furthermore, the coatings can be used for magnetically-driven oil-water separation with a certain degree of recyclability. The oil-water separation efficiency of the coating can reach 92% and above. More importantly, the coating also has excellent mechanical stability and self-cleaning properties. Therefore, this cheap and environmentally friendly nano-Fe3O4/chitosan-based superhydrophobic coating has great potential for application.

Single-Atom Cu Nanozyme-Loaded Bone Scaffolds for Ferroptosis-Synergized Mild Photothermal Therapy in Osteosarcoma Treatment.

The rapid multiplication of residual tumor cells and poor reconstruction quality of new bone are considered the major challenges in the postoperative treatment of osteosarcoma. It is a promising candidate for composite bone scaffold which combines photothermal therapy (PTT) and bone regeneration induction for the local treatment of osteosarcoma. However, it is inevitable to damage the normal tissues around the tumor due to the hyperthermia of PTT, while mild heat therapy shows a limited effect on antitumor treatment as the damage can be easily repaired by stress-induced heat shock proteins (HSP). This study reports a new type of single-atom Cu nanozyme-loaded bone scaffolds, which exhibit exceptional photothermal conversion properties as well as peroxidase and glutathione oxidase mimicking activities in vitro experiments. This leads to lipid peroxidation (LPO) and reactive oxygen species (ROS) upregulation, ultimately causing ferroptosis. The accumulation of LPO and ROS also contributes to HSP70 inactivation, maximizing PTT efficiency against tumors at an appropriate therapeutic temperature and minimizing the damage to surrounding normal tissues. Further, the bone scaffold promotes bone regeneration via a continuous release of bioactive ions (Ca2+ , P5+ , Si4+ , and Cu2+ ). The results of in vivo experiments reveal that scaffolds inhibit tumor growth and promote bone repair.

Microbubble oscillation on localized heat source affected by dissolved gases in water

Recently, we demonstrated that the local heating of degassed water can generate water vapor microbubbles and induce a rapid flow around the bubble. Although flow generation involves the self-excited oscillation of bubbles at a local heating point, the conditions under which the bubbles oscillate are not fully understood. In this study, the dependence of microbubble size and oscillation frequency on the concentration of non-condensable gases in water was investigated. A continuous-wave laser beam was focused on a β-FeSi2 thin film, and water was locally heated using the photothermal conversion properties of the film. The results showed that the lower the concentration of non-condensable gases dissolved in water, the smaller the bubble size and the higher the oscillation frequency. Furthermore, it was found that the bubbles oscillate when the amount of non-condensable gas absorbed by the bubbles, i.e., the bubble size, falls below a specific level. This study can provide a new understanding of the bubble oscillation mechanism and lead to the development of fluid control technology using bubbles.

Post-synthetic Rhodium (III) Complexes in Covalent Organic Frameworks for Photothermal Heterogeneous C-H Activation.

Although photocatalytic C-H activation has been realized by using heterogeneous catalysts, most of them require high-temperature conditions to provide the energy required for C-H bond breakage. The catalysts with photothermal conversion properties can catalyze this reaction efficiently at room temperature, but so far, these catalysts have been rarely developed. Here, we construct bifunctional catalysts Rh-COF-316 and -318 to combine photosensitive covalent organic frameworks (COFs) and transition-metal catalytic moiety using a post-synthetic approach. The Rh-COF enable the heterogeneous C-H activation reaction by photothermal conversion for the first time, and exhibit excellent yields (up to 98 %) and broad scope of substrates in [4+2] annulation at room temperature, while maintaining the high stability and recyclability. Significantly, this work is the highest yield reported so far in porous materials catalyzing C(sp2)-C(sp2) formation at room temperature. The excellent performances can be attributed to the COF-316, which enhances the photothermal effect (ΔT=50.9 °C), thus accelerating C-H bond activation and the exchange of catalyst with substrates.

Post‐synthetic Rhodium (III) Complexes in Covalent Organic Frameworks for Photothermal Heterogeneous C−H Activation

AbstractAlthough photocatalytic C−H activation has been realized by using heterogeneous catalysts, most of them require high‐temperature conditions to provide the energy required for C−H bond breakage. The catalysts with photothermal conversion properties can catalyze this reaction efficiently at room temperature, but so far, these catalysts have been rarely developed. Here, we construct bifunctional catalysts Rh‐COF‐316 and ‐318 to combine photosensitive covalent organic frameworks (COFs) and transition‐metal catalytic moiety using a post‐synthetic approach. The Rh‐COF enable the heterogeneous C−H activation reaction by photothermal conversion for the first time, and exhibit excellent yields (up to 98 %) and broad scope of substrates in [4+2] annulation at room temperature, while maintaining the high stability and recyclability. Significantly, this work is the highest yield reported so far in porous materials catalyzing C(sp2)−C(sp2) formation at room temperature. The excellent performances can be attributed to the COF‐316, which enhances the photothermal effect (ΔT=50.9 °C), thus accelerating C−H bond activation and the exchange of catalyst with substrates.

Chitosan-derived carbon aerogel modified with lignin carbon quantum dots for efficient solar evaporation

Solar-powered desalination technology offers outstanding benefits in providing clean, safe water and alleviating global freshwater shortages. However, the low evaporation rate, poor salt resistance and high cost limit the development of solar evaporators. Inspired by plant transpiration, a solar evaporator was fabricated from lignin carbon quantum dots (LCQDs) modified chitosan carbon aerogel (C-LCDCA). The introduced LCQDs and low carbonization temperature (280 °C) ensured hydrophilic properties while maintaining the three-dimensional porous structure, as well as improved light absorption and photothermal conversion properties. The evaporation rate of C-LCDCA under one sun was 1.71 kg m−2h−1. Interestingly, C-LCDCA promoted the local crystallization of salt crystals and realized the collection. The evaporation performance of the evaporator can be adapted to different evaporation situations by making simple layer adjustments. The optimal C-LCDCA evaporator (4-layer integrated) surpassed the limit of the interfacial evaporation system, with evaporation rate and efficiency up to 2.32 kg m−2h−1 and 113.9 % respectively under one sun, and with strong salt-rejecting (no obvious salt crystallization in 20 wt% brine for 8 h) and excellent self-cleaning ability (0.3 g NaCl re-dissolved back to 15 wt% brine in 15 min). With superior evaporation performance, the condensate obtained by the evaporator in simulated seawater evaporation experiments met the World Health Organization’s drinking water standards, and enabled effective treatment of industrial wastewater containing heavy metal ions (Cr3+, Fe3+, Pb2+, and Ni2+), nanoplastics (500 and 50 nm), and dyes (Rhodamine B, Methyl Orange, and Malachite green). These findings provide new ideas for the preparation of efficient, salt-rejecting, self-cleaning, and environmentally friendly solar evaporators and advance the practical application of sustainable water purification technologies.

Tannin-based modified graphene oxide anti-corrosion composite coating with favourable corrosion inhibition, self-healing and photothermal conversion properties

Inspired by the polyphenol hydroxyl structure of tannic, this work reports a graphene-based anti-corrosive composite coating that integrates inhibition, self-healing and photothermal conversion properties. Electrochemical tests in solution and scratch phases illustrate that the inhibition effect of modified particles provide passive healing. For intact coating, after 50 days of immersion, the G2T2F8/AR coating maintains the highest impedance modulus throughout the entire process (1.04×1010 Ω cm2). More importantly, the scratch coating can achieve active healing of photothermal conversion through NIR stimulation. The combination of exogenous and intrinsic healing mechanisms enables the coating to own excellent self-healing and anti-corrosion effects.

RHTC/HO-BNNS structure collaboratively improves thermal conductivity and photothermal conversion properties of phase change materials

The application of phase change materials (PCMs) to improve the efficiency of solar energy has been widely studied. However, most composite PCMs can only maintain high photothermal conversion performance in solid phase environment. To expand the application range of PCM in solar energy field, a flexible composite film which can stably exist in both solid and aqueous environments was prepared. Polyethylene glycol (PEG) as the temperature control core, hydroxyl boron nitride nanosheets (HO-BNNS) and carboxy-rich carbon (RHTC) as the thermally conductive filler and high photothermal converter, respectively, and polyvinylidene fluoride (PVDF) as the flexible supporting material. RHTC/HO-BNNS, as a key bridge, forms a thermal conductivity and photothermal conversion network in the composite film, making its photothermal conversion storage efficiency up to 92.1%, and its thermal conductivity 4 times higher than that of pure PEG. Together with the excellent mechanical strength (2.35 MPa), composite film can be operate at night solar evaporators. It can both improve the effective utilization of solar energy and accelerate the progress of seawater desalination, providing a new idea for expanding the application of PCM.