Photothermal Conversion Efficiency Research Articles

Radical‐Induced Photochromic Silver(I) Metal–Organic Frameworks: Alternative Topology, Dynamic Photoluminescence and Efficient Photothermal Conversion Modulated by Anionic Guests

AbstractPhotogenerated radicals are an indispensable member of the state‐of‐the‐art photochromic material family, as they can effectively modulate the photoluminescence and photothermal conversion performance of radical‐induced photochromic complexes. Herein, two novel radical‐induced photochromic metal–organic frameworks (MOFs), [Ag(TEPE)](AC) ⋅ 7/4H2O ⋅ 5/4EtOH (1) and [Ag(TEPE)](NC) ⋅ 3H2O ⋅ EtOH (2), are reported. Distinctly different topological networks can be obtained by judiciously introducing alternative π‐conjugated anionic guests, including a new topological structure (named as sfm) first reported in this work, describing as 4,4,4,4‐c net. EPR data and UV–Vis spectra prove the radical‐induced photochromic mechanism. Dynamic photochromism exhibits tunability in a wide CIE color space, with a linear segment from yellow to red for 1, while a curved coordinate line for 2, resulting in colorful emission from blue to orange. Moreover, photogenerated TEPE* radicals effectively activate the near‐infrared (NIR) photothermal conversion effect of MOFs. Under 1 W cm−2 808 nm laser irradiation, the surface temperatures of photoproducts 1* and 2* can reach ~160 °C and ~120 °C, respectively, with competitive NIR photothermal conversion efficiencies η=51.8 % (1*) and 36.2 % (2*). This work develops a feasible electrostatic compensation strategy to accurately introduce photoactive anionic guests into MOFs to construct multifunctional radical‐induced photothermal conversion materials with tunable photoluminescence behavior.

A dual-directional metamaterial perfect absorber base on Al2O3 etched cross cavity in the visible and near-infrared ranges

Due to their unique properties, metamaterial perfect absorbers have been widely used in such fields as solar energy absorption, seawater desalination, sensing and so on. Recently, ultra-wide band perfect absorbers and multi-narrow band perfect absorbers are studied and reported. However, there are a few researches on metamaterial perfect absorbers with both narrow-band and wide-band absorption properties. In this paper, we propose a dual-directional perfect absorber which can switch between wide band absorption and narrow band absorption. It consists of a multi-layer planar structure topped by a pattern layer being arranged periodically. In the wavelength range of 600 nm to 2000 nm, when the incident light is vertically incident from the upper surface of the structure, there will be three resonance absorption peaks, locating at 863 nm, 875 nm and 1135 nm, and the absorption rates will reach to 99.51 %, 99.61 % and 99.58 %, respectively. The analysis demonstrates that the structure has good sensing performance in the environment of different refractive index. When the incident light is incident from the lower surface of the structure, the absorber exhibits broadband absorption with an average absorption rate of 98.04 % (600 ∼ 2000 nm). When the temperature reaches 1000 K, the total photothermal conversion efficiency of the absorber can still reach more than 92 %. In addition, our research shows that the structure is independent of polarization. All these features promise for our proposed dual-function perfect absorber to realize diverse applications in the fields of sensing, detection, sunlight acquisition, optical conversion devices, and so on.

TME-Triggered Degradable Phototheranostic Nanoplatform for NIR-II Fluorescence Bioimaging-Guided Phototherapies and Immune Activation.

The low therapeutic efficacy and potential long-term toxicity of antitumor treatments seriously limit the clinical application of phototherapies. Herein, we develop a degradable phototheranostic nanoplatform for NIR-II fluorescence bioimaging-guided synergistic photothermal (PTT) and photodynamic therapies (PDT) and immune activation to inhibit tumor growth. The phototheranostic nanoplatform (CX@PSS) consists of multidisulfide-containing polyurethane loaded with a photosensitizer CX, which can be specifically degraded in the GSH overexpressed tumor microenvironment (TME) and exhibits good NIR-II fluorescence, photodynamic, and photothermal properties. Under 808 nm light irradiation, CX@PSS exhibits efficient photothermal conversion and ROS generation, which further induces immunogenic cell death (ICD), releasing tumor-associated antigens and activating the immune response. In vitro and in vivo studies confirm the potential of CX@PSS in NIR II FL imaging-guided tumor treatments by synergistic PTT, PDT, and immune activation. This work is expected to provide a new pathway for clinical applications of imaging-guided tumor diagnosis and treatments.

Multifunction integration within magnetic CNT-bridged MXene/CoNi based phase change materials

Developing advanced nanocomposite phase change materials (PCMs) integrating zero-energy thermal management, microwave absorption, photothermal therapy and electrical signal detection can promote the leapfrog development of flexible wearable electronic devices. For this goal, we propose a multidimensional collaborative strategy combining two-dimensional (2D) MXene nanosheets with metal-organic framework-derived one-dimensional (1D) carbon nanotubes (CNTs) and zero-dimensional (0D) metal nanoparticles. After encapsulating paraffin wax (PW) in three-dimensional (3D) networked multidimensional MXene/CoNi–C, the resulting composite PCMs exhibit excellent thermal energy storage capacity and long-term thermally reliable stability. Benefiting from the synergistically enhanced photothermal effects of CNTs, Co/Ni nanoparticles and MXene, PW@MXene/CoNi–C can capture photons efficiently and transfer phonons quickly, yielding an ultrahigh photothermal conversion and storage efficiency of 97.5%. Additionally, PW@MXene/CoNi–C composite PCMs exhibit high microwave absorption with a minimum reflection loss of −49.3 ​dB at 8.03 ​GHz in heat-related electronic application scenarios. More attractively, the corresponding flexible phase change film can simultaneously achieve thermal management and electromagnetic shielding of electronic devices, as well as photothermal therapy and electrical signal detection for individuals. This functional integration design provides an important reference for developing advanced flexible multifunctional wearable materials and devices.

Hydrogenated oxide material-based hyperthermia and radiotherapy: A new treatment option for esophageal squamous carcinoma.

e16127 Background: Radiotherapy (RT) is the mainstay of esophageal squamous carcinoma (ESCC) treatment, and hyperthemia could exert synergistic effects to refractory diseases. Hydrogenated oxide material (HMO) is a newly developed photothermal agent, featured by selectively targeting tumors, high photothermal conversion efficiency under 1064 nm near-infared (NIR) illumination and safe degradation. This study aims at investigating the combination effects of HMO-based hyperthermia and RT in ESCC. Methods: mEC25 murine ESCC cells were cultured and treated with RT alone (prescribed cumulative dose of 10Gy), HMO-based hyperthermia (incubated with 100ug/ml HMO for 20min and irradiated with 1064nm NIR continuously for 15min) or combination therapy (RT followed by HMO-based hyperthermia). FLIR-One was applied to monitor temperature alterations in HMO-based hyperthermia. Flow cytometry was performed to detect apoptosis rates 24h after treatment. Results: The temperature was increased by 21.3[19.8-23.7]℃ after NIR irradiation. The apoptosis rates were 19.4%[19.4%, 19.5%], 43.8%[43.6%, 44.0%] and 61.4%[58.5%, 61.8%] in RT alone, HMO-based hyperthermia and combination therapy group respectively. Considerably low apoptosis rates were observed in HMO-incubation and NIR-irradiation only groups, which was 6.2% and 6.6% respectively, similar to that of treatment-naive cells. Conclusions: The combination of HMO-based hyperthermia and RT provided a promising treatment modality for ESCC, while its effects in rodent models and potentials in clinical practice merit further investigations.

Harnessing bright upconversion luminescence from PEG-coated NaGdF4:Ho3+/Yb3+ nanoparticles for contrast enhancement in dual mode OCT imaging and optical temperature sensing

In this work, authors synthesized the Polyethylene Glycol (PEG) coated NaGdF4:Ho3+/Yb3+ nanoparticles using the thermal decomposition reaction route. Our primary objective was to comprehensively evaluate their suitability for augmenting image contrast, particularly within the intricate domain of Swept Source Optical Coherence Tomography (SSOCT) and photo-thermal Optical Coherence Tomography (PTOCT) imaging modalities. Our meticulous inquiry yielded the revelation of extraordinary upconversion emissions, which emanated from the distinct transitions of Ho3+ ions, most notably the 5F4(5S2)→ 5I8 and 5F5→ 5I8 transitions. These transitions manifested as strikingly vibrant green emissions, precisely at the 539 nm and 661 nm wavelengths. Furthermore, we investigated the underlying upconversion mechanism, delving deeply into the elucidation of decay times and the nanoparticles' ability to transform incident radiation into thermal energy. Impressively, these nanoparticles exhibited a noteworthy photo-thermal conversion efficiency, specifically measured at an impressive 47.4 % along with the bright green luminescence. Our study also extended to bio-compatibility, where we achieved highly encouraging outcomes. Following 24 h of incubation with HeLa cells treated with UCNP-PEG, we ascertained a compelling cell survival rate exceeding 80 %, underscoring the favorable biocompatibility of these nanoparticles. Moreover, these nanoparticles demonstrated a conspicuous thermal sensitivity, quantified at 5.1 × 10−3 K−1 at 380K, thus signaling their potential for precision temperature monitoring and could be applied at the cellular level.

A review of 3D monolithic carbon-based materials with a high photothermal conversion efficiency used for solar water vapor generation

A review of 3D monolithic carbon-based materials with a high photothermal conversion efficiency used for solar water vapor generation

Isoindigo nanoparticles for photoacoustic imaging-guided tumor photothermal therapy

The key factor in photothermal therapy lies in the selection of photothermal agents. Traditional photothermal agents generally have problems such as poor photothermal stability and low photothermal conversion efficiency. Herein, we have designed and synthesized an isoindigo (IID) dye. We used isoindigo as the molecular center and introduced common triphenylamine and methoxy groups as rotors. In order to improve the photothermal stability and tumor targeting ability, we encapsulated IID into nanoparticles. As a result, the nanoparticles exhibited high photothermal stability and photothermal conversion efficiency (67%) upon 635 nm laser irradiation. Thus, the nanoparticles demonstrated a significant inhibitory effect on live tumors in photothermal therapy guided by photoacoustic imaging and provided a viable strategy to overcome the treatment challenges.

Enhanced corrosion resistance and photothermal antibacterial properties of MAO/Fe/GO composite coating on Mg alloy

Fast degradation and postoperative bacterial infection are two main limitations for clinical application of Mg-based implants. Herein, we report a dual functional coating on micro-arc oxidation treated AZ31 Mg alloy (named MAO/Fe/GO) with the integration of graphene oxide (GO) and ferric oxyhydroxide (FeOOH). The photothermal conversion efficiency of MAO/Fe/GO composite coating is as high as 43.2%. Moreover, the MAO/Fe/GO composite coating exhibits enhanced corrosion resistance, antimicrobial activity under 808 nm irradiation, and good biocompatibility.

A multifunctional nanoplatform for dual-readout visual detection and real-time inactivation of Staphylococcus aureus with nanozymes and Au nanorods

Pathogenic bacteria pose a significant burden on global public health. To ensure food safety and prevent the spread of foodborne diseases, the multifunctional technical platforms for rapid detection and inactivation of pathogens are urgently needed. Herein, a new dual-readout detection and bacterial inactivation nanoplatform was constructed based on K10P2W18Fe4(H2O)2O68@polydopamine (P2W18Fe4@PDA) nanozymes and Au nanorods (AuNRs). The target bacteria such as Staphylococcus aureus (S. aureus) was firstly specifically isolated by the Fe3O4-Apt in complex sample matrices. Then, the isolated bacteria (Fe3O4-Apt-S. aureus) were strongly bound by the P2W18Fe4@PDA nanozymes with excellent peroxidase-like activity and highly efficient photothermal conversion. Accordingly, bacteria can be sensitively detected with monochrome signal catalyzed by the nanozyme (3, 3′, 5, 5′-tetramethylbenzidine (TMB) oxidation) and multicolor signal produced by TMB2+ etching AuNRs. With the assay, as low as 29 CFU/mL S. aureus could be distinguished. Meanwhile, over 99% S. aureus in the magnetic separation can be effectively inactivated by 808 nm Near-infrared (NIR) light within 10 min. Moreover, S. aureus was detected successfully in spiked milk with a recovery rate of 98.64%–109.04% using this method, indicated that the method held significant promise for applications in food analysis and control.

Enhanced Peroxymonosulfate activation via Bi 12 CoO 20 /rGO with Near‐Infrared Photothermal Response for Antibiotics Degradation

Against the backdrop of escalating antibiotic pollution, this study presents a novel approach to remediation using a photothermal heterogeneous Fenton‐like catalyst, Bi12CoO20/rGO, which efficiently activates peroxymonosulfate (PMS) under near‐infrared (NIR) light. This catalyst capitalize on the NIR absorption capabilities of Bi12CoO20 and the electron transfer properties of reduced graphene oxide (rGO). The restored sp2 structure of rGO serves as a conduit for electron transfer, crucial for the redox cycle of Co2+/Co3+ that facilitates PMS activation. Moreover, the incorporation of rGO significantly boosts the NIR absorption capacity of Bi12CoO20, thereby enhancing the photothermal conversion efficiency of the composite and further promoting PMS activation. This synergy enables efficient light‐to‐heat conversion and PMS activation, generating reactive oxygen species (ROS) essential for antibiotic degradation. Using levofloxacin (LVX) as a representative pollutant, the developed system achieves an impressive 99% degradation rate within just 30 min under Bi12CoO20/rGO + PMS + NIR conditions. Moreover, this approach demonstrates robust stability and adaptability across diverse water compositions and pH ranges. Its eco‐friendly nature and renewable characteristics position it as a promising solution for combating antibiotic pollution through photothermal Fenton‐like technology, thereby harnessing solar energy for environmental remediation and fostering sustainable water management practices.

Proton‐conducting hydrogel electrolytes with tight contact to binder‐free MXene electrodes for high‐performance thermally chargeable supercapacitor

AbstractThermally chargeable supercapacitors (TCSCs) have offered exceptional energy‐converting efficiency for absorbing human epidermal heat and generating and storing electrical energy, which then realize continuous power supply to electronic devices, such as sensors and wearable electronic products, in a wide range of practical significance. Here, we proposed a flexible TCSC by attaching binder‐free Ti3C2Tx MXene@PPy electrodes on both ends of the H3PO4@P(AM‐co‐AA‐co‐AYP K+) hydrogel electrolyte, which exhibits a large thermal power of 35.2 mV K−1 at 50% relative humidity and maximum figure of merit of 2.1. The high performances of the fabricated devices can be attributed to the tunable electrical, thermodynamic, thermoelectric, and mechanical properties of the hydrogel electrolyte by adjusting the acid content and the proportion of zwitterionic compound AYP K+ in the hydrogel, and the high photothermal conversion efficiency and electrochemical performance of the electrodes. Moreover, the stable and outstanding thermofvoltage output (∼200 mV) under different time scenarios of the TCSC makes it possible to drive a strain sensor, accomplishing the objectives of a human activity monitor.

Neutral Cyanine: Ultra-Stable NIR-II Merocyanines for Highly Efficient Bioimaging and Tumor-Targeted Phototheranostics.

Fluorescence imaging (FLI)-guided phototheranostics using emission from the second near-infrared (NIR-II) window show significant potential for cancer diagnosis and treatment. Clinical imaging-used polymethine ionic indocyanine green (ICG) dye is widely adopted for NIR fluorescence imaging-guided photothermal therapy (PTT) research due to its exceptional photophysical properties. However, ICG has limitations such as poor photostability, low photothermal conversion efficiency (PCE), short-wavelength emission peak, and liver-targeting issues, which restrict its wider use. In this study, two ionic ICG derivatives are transformed into neutral merocyanines (mCy) to achieve much-enhanced performance for NIR-II cancer phototheranostics. Initial designs of two ionic dyes show similar drawbacks as ICG in terms of poor photostability and low photothermal performance. One of the modified neutral molecules, mCy890, shows significantly improved stability, an emission peak over 1000nm, and a high photothermal PCE of 51%, all considerably outperform ICG. In vivo studies demonstrate that nanoparticles of the mCy890 can effectively accumulate at the tumor sites for cancer photothermal therapy guided by NIR-II fluorescence imaging. This research provides valuable insights into the development of neutral merocyanines for enhanced cancer phototheranostics.

Polyethylene glycol/melamine foam composite phase change materials modified by CdS/Ag exhibits high photothermal conversion performance

CdS has been shown to be an excellent photon trap with strong absorption of light at visible and near-infrared wavelengths. The use of CdS for phase change material (PCM) modification can significantly improve its photothermal conversion performance. However, due to the unique energy band structure of CdS, the difficulty in electron conduction leads to poor thermal conductivity. This problem can be improved by introducing high thermal conductivity nanometals for modification, however, the effective combination of CdS and nanometals has been challenging. In this study, a new preparation strategy is demonstrated, in which Ag nanoparticles (NPs) with similar lattice parameters and crystalline coordination to CdS is first introduced on the surface of carbonized melamine foam (CMF), followed by the introduction of CdS NPs. This similar structure helps to form a better interfacial bond between CdS and Ag. The resulting stabilized structure enables the composite phase change material (CPCM) to achieve 96.1 % PEG loading with an ultra-high photothermal conversion efficiency of 94.6 %, thermal conductivity of 0.61 W/m∙K, and excellent antimicrobial activity. This study provides valuable guidance for the engineering design of CPCM with high photothermal conversion performance and suggests its practical application value in seawater evaporation and thermal management of medical devices.

Self-assembled IR dye/mitoxantrone loaded Porphysomes nanosystem for enhanced combinatorial chemo-photothermal cancer therapy

Chemo-photothermal therapy (PTT) is an emerging non-invasive cancer treatment modality. Light-responsive porphysomes (DPP IR Mtx @Lipo NPs) nanosystems ablate breast cancer cells upon oxidative stress and hyperthermia. The unique self-assembled porphysomes were formed spherical shape in the size range of 150 ± 30 nm formed by the co-assembly of porphyrins along with IR 775 and chemotherapeutic drug, Mitoxantrone (Mtx), forming a camouflaged nanosystem (DPP IR Mtx @Lipo NPs, porphysomes). The advent of the prepared porphysomes aids in proper tuning of NIR absorbance improving singlet oxygen species generation among other anticancer drugs. The eminent release of DPP and adjuvant chemo-drug, Mitoxantrone from the self-assembled porphysomes is triggered by IR 775, a NIR photosensitizer upon laser irradiation. These multifunctional DPP IR Mtx @Lipo NPs have an efficient photothermal conversion efficiency of 65.8% as well as bioimaging properties. In-vitro studies in 2D and 3D models showed a significant cell death of 4T1 cells via the apoptotic pathway when irradiated with NIR laser, causing minimal damage to nearby healthy cells. DPP IR Mtx @Lipo NPs exhibited commingled PDT/PTT interdependent via NIR laser exposure, leading to mitochondrial disruption. Interestingly, the transient transfection using p53-GFP in cancer cells followed by DPP IR Mtx @Lipo NPs treatment causes rapid cell death. The activation of p53-dependent apoptosis pathways was vividly expressed, evidenced by the upregulation of Bax and increased pattern of Caspase-3 cleavage. This effect was pronounced upon transfection and induction with DPP IR Mtx @Lipo NPs, particularly in comparison to non-transfected malignant breast cancer 4T1 cells.

Europium-Based Coordination Polymer-Modified Vanadium Sulfide Nanocomposite with High Photothermal Conversion Efficiency as a Powerful Photothermal and Four-Mode Imaging Technique

Europium-Based Coordination Polymer-Modified Vanadium Sulfide Nanocomposite with High Photothermal Conversion Efficiency as a Powerful Photothermal and Four-Mode Imaging Technique

Bottom-up synthesis of nanoflowers for combined PTT/TDT/ST therapy of osteosarcoma

As a common malignant bone tumor in adolescents, osteosarcoma (OS) possesses a very poor prognosis and lacks effective treatments. In this study, we developed a multifunctional nanotherapeutic agent (WSe2/AIPH/GOx) that can combine photothermal therapy (PTT) /thermodynamic therapy (TDT) /starvation therapy (ST) against OS. The prepared WSe2/AIPH/GOx exhibited a high photothermal conversion efficiency of 37.3% under 808 nm near-infrared laser irradiation, which could effectively eliminate tumor cells. In addition, the local high temperature caused by photothermal heat induces the rapid release and decomposition of AIPH, generating oxygen-independent alkyl radicals that promote tumor cell death in the hypoxic microenvironment. More importantly, the introduction of GOx depletes glucose to starve tumor cells on the one hand, and on the other hand can indirectly increase the thermal sensitivity of cells. In vivo experiments have demonstrated that WSe2/AIPH/GOx can effectively inhibit tumor growth in mice due to the combined effects of multiple therapies. Overall, this work provides an effective strategy for potential osteosarcoma treatment based on combination therapies.

Photoacoustic Imaging-Guided Self-Adaptive Hyperthermia Supramolecular Cascade Nano-Reactor for Diabetic Periodontal Bone Regeneration.

Commencing with the breakdown of the diabetic osteoimmune microenvironment, multiple pathogenic factors, including hyperglycemia, inflammation, hypoxia, and deleterious cytokines, are conjointly involved in the progression of diabetic periodontal bone regeneration. Based on the challenge of periodontal bone regeneration treatment and the absence of real-time feedback of blood oxygen fluctuation in diabetes mellitus, a novel self-adaptive hyperthermia supramolecular cascade nano-reactor ACFDG is constructed via one-step supramolecular self-assembly strategy to address multiple factors in diabetic periodontal bone regeneration. Hyperthermia supramolecular ACFDG possesses high photothermal conversion efficiency (32.1%), and it can effectively inhibit the vicious cycle of ROS-inflammatory cascade through catalytic cascade reactions, up-regulate the expression of heat shock proteins (HSPs) under near-infrared (NIR) irradiation, which promotes periodontal bone regeneration. Remarkably, ACFDG can provide real-time non-invasive diagnosis of blood oxygen changes during periodontal bone regeneration through photoacoustic (PA) imaging, thus can timely monitor periodontal hypoxia status. In conclusion, this multifunctional supramolecular nano-reactor combined with PA imaging for real-time efficacy monitoring provides important insights into the biological mechanisms of diabetic periodontal bone regeneration and potential clinical theranostics.

Polymer foam fabricated via surfactant foaming method enables high-performance solar interfacial evaporation

Solar interfacial evaporation is considered as a low energy consumption, low cost, and sustainable desalination technology. However, its practical application is still limited by complex preparation processes and low photothermal conversion efficiency. In this work, we report novel polymer foam (Agar/SA/GO-Ag composite foam). It is prepared by simple and convenient surfactant foaming and in-situ reduction methods and consists of graphene oxide (GO) and silver nanoparticles (Ag NPs) (photothermal conversion medium) as well as Agar and sodium alginate (SA) (basic skeleton) for use in solar-powered interfacial evaporation systems. The prepared foam has excellent wettability and achieves 96.7% light absorption in the full spectrum range. A high evaporation rate of 2.55 kg·m−2·h−1 and a high evaporation efficiency of 97.3% were obtained under the conditions of simulated sunlight (1.0 kW·m−2). Moreover, the foam exhibits good reusability in a 10-cycle test without obvious attenuation in evaporation performance. Foam is used for seawater desalination and wastewater purification, and the treated water meets the water quality standards of the World Health Organization (WHO) and the United States Environmental Protection Agency (USEPA). In short, this work demonstrates a sustainable strategy for low-cost and efficient solar-powered clean water production.

Novel BODIPY-based nano-biomaterials with enhanced D-A-D structure for NIR-triggered photodynamic and photothermal therapy

Near‐infrared (NIR) responsive nanoparticles are an important platform for multimodal phototherapy. Importantly, the simultaneous NIR-triggered photodynamic (PDT) and photothermal (PTT) therapy is a powerful approach to increase the antitumor efficiency of phototherapic nanoparticles due to the synergistic effect. Herein, a boron dipyrromethene (BODIPY)-based amphiphilic dye with enhanced electron donor–acceptor-donor (D-A-D) structure (BDP-AP) was designed and synthesized, which could self-assemble into stable nanoparticles (BDP-AP NPs) for the synergistic NIR-triggered PDT/PTT therapy. BDP-AP NPs synchronously generated singlet oxygen (1O2) and achieved preeminent photothermal conversion efficiency (61.42%). The in vitro and in vivo experiments showed that BDP-AP NPs possessed negligible dark cytotoxicity and infusive anticancer performance. BDP-AP NPs provide valuable guidance for the construction of PDT/PTT-synergistic NIR nanoagents to improve the efficiency of photoinduced cancer therapy in the future.