Photothermal System Research Articles

Research on technical route and economic calculation of solar assisted carbon capture system

This paper takes a 600MW supercritical unit as the research object, and studies the technical route and economic situation of solar photothermal system as the heat source of reboiler of carbon capture system. Taking Monoethanolamine (MEA) as the research object to analyse its desorption energy consumption characteristics, the calculation results show that the carbon capture and regeneration energy consumption of the system is 3.90Gj/t CO2, calculated by the CO2 absorption rate of 85%. Three technical routes of solar assisted carbon capture systems are proposed, and the main thermal economic indexes of the two methods, such as unit coal consumption and thermal efficiency, using the fifth stage extraction steam as an independent heat source and cooperating with the solar photothermal system, are calculated and compared respectively. Based on this, the influence of investment cost and collector area on CO2 emission reduction cost and coal consumption is analysed. The results show that after adding the solar thermal system, the coal consumption of the unit is reduced by 2.5g/(kw) compared with the pure steam extraction heating unit and the thermal efficiency is increased by 0.9%. The CO2 emission reduction cost has a positive correlation trend with the investment cost, and the unit coal consumption has a negative correlation trend with the increase of the collector area.

Achieving structural white inspired by quasiordered microstructures in Morpho theseus

As one of the most fascinating phenomena, structural whiteness in natural organisms serves important functions in thermoregulation and mating. However, the architectures that cause visible broadband reflection are often in quasiordered distributions, which hinders systematic research on their color formation mechanisms. Here, through numerical analysis, the architectures in Morpho theseus scales are shown to be distributed in various tubular morphologies between tubular and gyroid structures. Then, the mechanism of structural white is discussed using the numerical model built with the combination of a periodic numerical framework and random elements. Thermodynamic experiments indicate that the white scales can efficiently help reduce the temperature of butterfly wings under a direct light beam. Our work provides a concise method for analyzing quasiordered structures. The methodology developed by this numerical model can facilitate a deep understanding of the performance improvement facilitated by these structural characteristics. Corresponding solutions can guide the design of nano-optical materials to achieve an efficient cooling, camouflage, and photothermal conversion system.

Inorganic Nanomaterials Used in Anti-Cancer Therapies:Further Developments

In this article, we provide an overview of the progress of scientists working to improve the quality of life of cancer patients. Among the known methods, cancer treatment methods focusing on the synergistic action of nanoparticles and nanocomposites have been proposed and described. The application of composite systems will allow precise delivery of therapeutic agents to cancer cells without systemic toxicity. The nanosystems described could be used as a high-efficiency photothermal therapy system by exploiting the properties of the individual nanoparticle components, including their magnetic, photothermal, complex, and bioactive properties. By combining the advantages of the individual components, it is possible to obtain a product that would be effective in cancer treatment. The use of nanomaterials to produce both drug carriers and those active substances with a direct anti-cancer effect has been extensively discussed. In this section, attention is paid to metallic nanoparticles, metal oxides, magnetic nanoparticles, and others. The use of complex compounds in biomedicine is also described. A group of compounds showing significant potential in anti-cancer therapies are natural compounds, which have also been discussed.

Establishment of a novel system for photothermal removal of ampicillin under near-infrared irradiation: Persulfate activation, mechanism, pathways and bio-toxicology

One of the most effective ways to address the problems of low solar spectrum utilization in photocatalysis and the high cost of persulfate activation technology is to create a cost-effective synergistic photothermal persulfate system. In this work, a brand-new composite catalyst called ZnFe2O4/Fe3O4@MWCNTs (ZFC) was developed to activate PDS (K2S2O8) from the aforementioned basis. ZFC's surface temperature could unbelievably reach 120.6 °C in 150 s together with the degrading synergistic system solution temperature could reach 48 °C under near-infrared light (NIR) in 30 min, thus accelerating the ZFC/PDS decolorization rate for reactive blue KN-R (150 mg/L) to 95% in 60 min. Furthermore, the ZFC's ferromagnetism bore it with good cycling performance, allowing it to maintain an 85% decolorization rate even after 5 cycles with OH·, SO4-·, 1O2, and O2–· dominating the degrading process. In the meantime, the DFT calculations of the kinetic constants for the entire process of S2O82- adsorption on Fe3O4 in dye degradation solution were in agreement with the outcomes of the experimental pseudo-first-order kinetic fitting. By analyzing the particular degradation route of ampicillin (50 mg/L) and the possible environmental impact of the intermediate using LC-MS and the toxicological analysis software (T.E.S.T.), respectively, it was shown that this system might function as an environmentally friendly method for removing antibiotics. This work may provide some productive research lines for the creation of a photothermal persulfate synergistic system and suggest fresh approaches to water treatment technology.

In-situ construction of Mn0.2Cd0.8S/NiB composite for highly efficient full spectrum-driven photocatalytic H2 evolution

Development of efficient, economical and stable photocatalysts that can maximize the utilization of ultraviolet (UV), visible (Vis) and near-infrared (NIR) light for photocatalytic H2 evolution remains a challenge. Herein, polyhedral Mn0.2Cd0.8S (MCS) modified with amorphous NiB nanoparticles was rationally constructed by in-situ synthesis method. Compared to MCS, the optimized MCS/NiB composite exhibited much superior activity with the H2 evolution rate of 21.6, 29.1, 35.4 and 45.6 mmol g–1 h–1 under Vis (420–780 nm), Vis-NIR (420–1100 nm), UV-Vis (350–780 nm) and UV-Vis-NIR (300–1100 nm) light irradiation, respectively. The enhanced activity was attributed firstly to high charge carrier separation efficiency and adequate active reaction sites due to the modification of NiB co-catalyst and secondly to the enhanced photothermal effect owing to the introduction of full spectrum-responsive NiB. This work provides a new perspective for designing photothermal effect-enhanced photocatalytic system.

Kerr effect on optical induced transparency and group delays in a photothermal cavity

The thermal-induced nonlinear effect in a micro-cavity with small mode volume is extremely important for studying the optical cavity’s physical properties. In this work, we discuss the Kerr effect acting on the photothermally induced transparency (PTIT) and group delays in a photothermal cavity. We analyze the optical bistability with the thermal and Kerr nonlinear effects in the photothermal system, which directly impacts the dynamical stability and the threshold for bistability, eventually leading to an increase in the number of photons in the steady state. Meanwhile, the Kerr nonlinear effect greatly modifies the Fano-like PTIT in the system with photothermal effect, and the window is effectively compensated to symmetrical PTIT by Kerr-induced cavity frequency redshift. A group delay and advance are observed in the phase of the transmitted probe field, which enables light to be stored in the milliseconds range. The results demonstrate the possibility of enhancing or steering the performance of PTIT and group delay in nonlinear optical cavities, and it will find some applications in optical sensing and communications.

Antibacterial, photothermal and stable Ag-titanium-oxo-clusters hydrogel designed for wound healing

Titanium-oxo-clusters (TOCs), due to its precise, tunable structure and rich properties, have been widely used in many fields. However, application of TOCs is greatly limited in biomedical area owing to the impact of its own performances, for example, unstable structure, lack of antibacterial and anti-inflammatory properties required as biomedical materials. In this work, we developed a novel stable, excellent antibacterial and anti-inflammatory properties Ag-Titanium-oxo-cluster (Ag-TOC, Ag9Ti4) with active site Ag and salicylic acid by one-step solvothermal method, through introducing silver and salicylic acid. Then, the Ag9Ti4 cluster was introduced into the dopamine-containing hydrogel system, the results in vitro indicated this Ag9Ti4 cluster hydrogel system possesses good antibacterial and photothermal properties. Moreover, the results in vivo indicated the Ag9Ti4 hydrogel system showed better anti-inflammatory and wound healing ability under NIR condition. Combined with its excellent properties, we believed that the construction of antibacterial, photothermal and stable Ag-TOC hydrogel system can provide a new strategy for the expanding biomedical applications of TOCs.

Heat transfer and mechanical characteristics of the absorber in solar photo-thermal power generation system

In order to solve the problems of thermal fatigue, high temperature gasification and low temperature solidification of the heat receiver, a numerical calculation model for the heat transfer function of the tower type solar thermal power gener?ation high temperature receiver is proposed. A perfect analysis method is used for the simulation, and a thermal simulation program for predicting the heat gain of the solar thermal energy tower is compiled. In this paper, considering the various field connection characteristics, numerical value and distribution of convective heat transfer coefficient of the heat absorption medium, the temperature of the outer wall of the heat pipe absorption, and the thermal image conversion work in a non-uniform heat flow boundary area of a model of heat receiver was studied. The experiments show that when the flow rate of molten salt in the tube increases from 1 m/s to 2 m/s, the heat collection efficiency of the heat collection increases rapid?ly, while the flow time is more 3 m/s, the heat collection efficiency increases more gradually. The efficiency of heat absorption of the heat receiver is in the middle of the heat receiver, which can achieve 88 of the thermal image conversion. In the same large enough value, the heat collected at the inlet and outlet of the heat sink is about 82. It is clear that the numerical simulation provides a reliable basis for the design engineering, and provide guidance for the design of a full control model of tower solar photovoltaic power generation.

Preparation and performance of a stimuli-responsive drug delivery system: novel light-triggered temperature-sensitive drug-loaded microcapsules.

Stimuli-responsive/smart drug delivery systems (DDSs), particularly those that use temperature as a stimuli-response factor to activate drug release, are the subject of recent research. A phase change material (PCM) is a popular thermally responsive material that can be used as a drug carrier and only when the system temperature is above the phase change point is the drug released following the phase change material changing from solid to liquid. In this study, a novel NIR light-triggered temperature-sensitive drug delivery system is developed for controllable release of acyclovir (ACV). For this purpose, a mixture of a phase change material (T38) and an ACV compound is first emulsified with copper oxide nanoparticles (CuO NPs) as a Pickering stabilizer and a photothermal conversion material, and then encapsulated with SiO2 to form a photothermal stimuli-responsive delivery system. This system shows a uniform spherical shape with a well-distinct core-shell structure, and is further experimentally proven to be able to controllably release drugs with solid-liquid transition of the phase change carrier upon temperature change. These results indicate that cumulative release of ACV can reach 51.2% at 40 °C within 20 hours, which is much higher than 27.3% release achieved below the melting point of T38. In addition, CuO NPs with excellent photothermal conversion ability endow the system with precisely controllable drug delivery via NIR light stimulation, where the cumulative drug release can reach 83.6% after 7 cycles of light stimulation, allowing controlled release at a specific time or location.

Prediction of structural mechanical properties of energy-saving materials for solar photovoltaic photo-thermal system based on deep learning

In order to study the annual operating efficiency of solar photovoltaic/photo-thermal collectors, this paper proposes a prediction of structural mechanical properties of energy-saving materials for solar photovoltaic photo-thermal systems based on deep learning. Based on the test data of a solar photovoltaic module, the performance of photovoltaic photo-thermal module is evaluated from the perspectives of the First law of thermodynamics, the Second law of thermodynamics, power generation efficiency and heat collection efficiency. The experimental results show that the working temperature difference increases from 6.8 K to 45.3 K, the normalized temperature difference increases from to, and the power generation efficiency decreases from 0.105 to 0.095 by 0.010, the percentage of change is 9.4%, the heat collection efficiency is reduced from 0.4534 to 0.2120 by 0.2414, and the reduction rate is 53%, compared with the generation efficiency and heat collection efficiency, the efficiency changes during the test period are relatively small. In conclusion for photovoltaic/photo-thermal components, environmental parameters have a greater impact on the heat collection efficiency.

Gold Nanorods and Polymer Micelles Mediated Dual TLR Stimulators Delivery System CPG@Au NRs/M-R848 Regulate Macrophages Reprogramming and DC Maturation for Enhanced Photothermal Immunotherapy of Melanoma.

Synergistic photothermal immunotherapy has emerged as a favorable therapeutic approach to fight cancer. However, design of an effective photothermal immunotherapy system to suppress tumor growth and simultaneously inhibit tumor metastases continues to be a challenge. Here a dual toll-like receptoragonists delivery system CPG@Au NRs/m-R848 for combined photothermal immunotherapy of melanoma is developed. CPG@Au NRs/m-R848 displays strong antitumor effects by promoting maturation of dendritic cells (DCs) and reprogramming of M2 macrophages into M1 phenotype. Moreover, immunogenic cell death (ICD) induced by photothermal ablation of Au NRs could synergistically produce in situ vaccination effect with CPG ODN and R848, generating systemic and lasting antitumor immunity. It is further proved that CPG@Au NRs/m-R848 treatment inhibits tumor growth in bilateral B16F10 tumors model by eliciting CD8+ T cell response. Overall, this work suggests that this strategy hold great potential in tumor immunotherapy by regulating tumor-associated macrophage polarization, triggering DCs maturation and inducing ICD.

NIR-responsive 5-Fluorouracil delivery using polydopamine coated polygonal CuS nanoplates for synergistic chemo-photothermal therapy on breast cancer

Herein, copper sulfide covellite nanoplates were developed by precipitating Cu2+ cations in an aqueous solution using H2S gas. The polygonal CuS nanoplates were further coated with polydopamine and chitosan for the development of a stimuli-responsive nanoplatform for cancer cell ablation. The intense absorption in the Near Infrared (NIR) region (700–1100 nm) has been fundamental for the application of the CuS & PDA nanoplates in photothermal therapy. Furthermore, 5-Fluorouracil was chosen as the model chemotherapeutic drug and encapsulated in the polydopamine layer to achieve synergistic chemo-photothermal therapy. To improve the biocompatibility, chitosan was introduced into the nanosystem and lastly folic acid was attached to the nanoplatform to target breast cancer cells so likely reducing damage to healthy tissues. The photothermal conversion efficiency of the nanoconjugate was examined using a NIR laser (808 nm). The in vitro cytotoxicity test and hemocompatibility tests of the nanoconjugate showed excellent biocompatibility and photothermal conversion efficiency under an 808 nm laser irradiation. Visualization of the nanoconjugate treated MCF-7 cells, using a fluorescence microscope displayed that the synthesized photothermal system is efficient in cancer therapy. In summary, the final conjugate CuS-5-FU-PDA@CS-FA with laser treatment shows cancer-killing properties by chemo-photothermal cancer ablation.

Near-Infrared Light-Responsive Size-Selective Lateral Flow Chip for Single-Cell Manipulation of Circulating Tumor Cells.

Accurately obtaining information on the heterogeneity of CTCs at the single-cell level is a very challenging task that may facilitate cancer pathogenesis research and personalized therapy. However, commonly used multicellular population capture and release assays tend to lose effective information on heterogeneity and cannot accurately assess molecular-level studies and drug resistance assessment of CTCs in different stages of tumor metastasis. Herein, we designed a near-infrared (NIR) light-responsive microfluidic chip for biocompatible single-cell manipulation and study the heterogeneity of CTCs by a combination of the lateral flow microarray (LFM) chip and photothermal response system. First, immunomagnetic labeling and a gradient magnetic field were combined to distribute CTCs in different regions of the chip according to the content of surface markers. Subsequently, the LFM chip achieves high single-cell capture efficiency and purity (even as low as 5 CTCs per milliliter of blood) under the influence of lateral fluid and magnetic fields. Due to the rapid dissolution of the gelatin capture structure at 37 °C and the photothermal properties of gold nanorods, the captured single CTC cell can be recovered in large quantities at physiological temperature or released individually at a specific point by NIR. The multifunctional NIR-responsive LFM chip demonstrates excellent performance in capture and site release of CTCs with high viability, which provides a robust and versatile means for CTCs heterogeneity study at the single-cell level.

Functionalized polydopamine nanospheres as in situ spray for photothermal image-guided tumor precise surgical resection

Surgical resection is a critical procedure for treatment of solid tumor, which commonly suffers from postoperative local recurrence due to the possibility of positive surgical margin. Although the widely used clinical imaging techniques (CT, MRI, PET, etc.) show beneficial effects in providing a macroscopic view of preoperative tumor position, they are still failing to provide intraoperative real-time imaging navigation during the surgery and need oral or intravenous injection contrast agents with risk of adverse effects. In this work, we present a nano-spray assisted photothermal imaging system for in vitro cells discrimination as well as in vivo visualization of tumor position and border that guides real-time precise tumor resection during surgery (even for tiny tumor less than 3 mm). Herein, the nano-spray were prepared by RGD peptide functionalized polydopamine (PDA-RGD) nanospheres with excellent photothermal conversion efficiency (54.27%), stability and reversibility, which target ανβ3 integrin overexpressed tumor cells. Such PDA-RGD serve as nanothermometers that convert and amplify biological signal to intuitive thermal image signal, depicting the tumor margin in situ. In comparison to conventional imaging techniques, our approach through topical spraying together with portable infrared camera has the characteristics of low cost, convenient, no radiation hazard, real-time intraoperative imaging-guidance and avoiding the adverse effects risk of oral or intravenous contrast agent. This technology provides a new universal tool for potentially assisting surgeons’ decision in real-time during surgery and aiding to improved outcome.

Sponge-Based Aerogels for Efficient Solar Steam Generation

As a new type of solar energy utilization, solar photothermal water evaporation system has the characteristics of high photothermal conversion efficiency and green environmental protection, which can be widely used in the field of seawater desalination and sewage treatment. The bagasse carbonized by high-temperature pyrolysis was used as the photo-absorption material, and the polyurethane sponge-based aerogel photo-thermal conversion material was prepared with the double-network composite aerogel constructed by chitosan and polyurethane sponge as the substrate. It has good evaporation stability and is suitable for portable evaporation equipment. Moreover, when the carbonization temperature of carbonized bagasse was 500 °C and the addition amount was 1%, the evaporation performance of aerogel was the best. In the wavelength range of 200~2500 nm, its absorption rate can reach 98.2%, and its evaporation rate can reach 2.04 kg m−2h−1 at 1 kW m−2. In addition, the aerosol has good stability in general seawater and alkaline sewage, and is an effective method for solving seawater and sewage.

Comment on "CO2 Footprint of Thermal Versus Photothermal CO2 Catalysis".

The previously published report by Wang et al. provides universal equations for evaluating the net CO2 emission via photothermal/thermal CO2 hydrogenation reactions in batch and flow reactors, respectively. However, it remains to be discussed whether the original feed amount or feed rate of H2 should be changed accordingly when the CO2 reduction rate is selected as the variable to investigate the net CO2 emission rate of the system. If not, the reaction would not be in accordance with the stoichiometric ratio, which is inconsistent with reality, bringing about the optimistic scenario in the assessment of CO2 footprint. This work has taken the potential relationship between the original feed amount or feed rate of H2 and CO2 conversion rate into account. The effects of CO2 conversion rate on the net CO2 emission rate in the photothermal catalytic system are re-examined, the obtained trends exhibit more challenging preconditions to achieve net-zero carbon emission than those in the work by Wang etal. The quantitative results indicate that green hydrogen source is indeed vital for carbon neutrality in photothermal CO2 catalysis. Here, the viewpoints will be worth considering and be seen as complementary to the proposed carbon emission assessment equations.

Narrow-band multi-component gas analysis based on photothermal spectroscopy and partial least squares regression method

In spectroscopic multi-component gas sensing, the crosstalk in the overlapping region of gas absorption spectra will affect the measurement accuracy. This paper reports a new multi-component gas analyzing method based on partial least squares regression (PLSR), which can retrieve target gas concentration and the composition and concentration of interfering gas from an overlapping narrow-band spectrum. Two overlapping absorption spectra (acetylene and ammonia) around 1530 nm are selected to simulate the absorption crosstalk phenomenon. We built a fiber-optic photothermal interferometry system to verify the method on two-component gases in the overlapping region. The training of the PLSR model was based on 63 sets of photothermal second-harmonic signals, which acquired from the gases composed by 100–700 ppm ammonia and 100–900 ppm acetylene. The prediction error of PLSR model achieved 3.84 % when tested by extra data.

Photothermal technique-enabled ambient production of microalgae biodiesel: Mechanism and life cycle assessment

Thermocatalytic (trans)esterification of oils/lipids to produce biodiesel is generally energy-consuming, reversible, and controlled by the equilibrium law. Herein, a light-induced photothermal process was illustrated to be highly efficient for biodiesel production (96.8 % yield) from microalgae lipids at room temperature enabled by a biomass-based SO3H-functionalized graphene-like heterogeneous catalyst (S-NGL-600), as optimized by response surface methodology. Infrared thermal imaging indicated that interfacial solar heating led to forming a local photothermal catalytic system, reaching 72.2 °C in 2 min. The local light heating was conducive to evaporation and removal of water from acid sites, resulting in local excess of microalgae lipids to facilitate the forward reaction. Notably, the photothermal catalyst was highly recyclable and exhibited a significantly higher conversion rate of microalgae lipids than industrially used catalyst H2SO4. Life cycle assessment suggested energy-saving advantage (0.87 MJ/MJ) and environmental protection (-89.42 CO2eq/MJ) of the photothermal-driven protocol for microalgae biodiesel production.

Biomass‐Inspired Solar Evaporator for Simultaneous Steam and Power Generation Enhanced by Thermal‐Electric Effect

Solar‐driven interfacial evaporation systems have been considered to achieve broad application prospects in the field of cogeneration of steam and electricity. However, the electricity generated is often independent of the photothermal system, hindering their integration. Compared with traditional materials such as metals and semiconductors, the application of biomass materials can solve the problems of high cost and environmental pollution in the expansion and relevance of interfacial evaporation technology. Herein, the solar evaporator composed of carbonized sphagnum palustre with cellulose fabric (CSPF) is fabricated for simultaneous steam production and power generation. Additionally, a device consisting of the CSPF and other accessories such as heating wires is designed to enhance steam production by self‐driven electrothermal heating. The self‐driven solar evaporator endows enhanced evaporation rates to 2.12 kg m−2 h−1 under electrothermal effect and the high electrical energy outputs of 520 mV. The solar evaporator has good salt tolerance and excellent cycle stability, maintaining a high evaporation rate in high‐salt solutions and after 24 cycles of testing. The outdoor evaporation tests reveal the encouraging performance of the steam and energy generators in real environment. Such superior performance of comprehensive device has great potential for integrated and sustainable application in cogeneration systems.

A flexible and highly efficient graphene-based photothermal evaporation device with independent water transport and photothermal absorption system

Solar interfacial evaporation is a new desalination technology, which has the advantages of low cost, low energy consumption, simple system and no pollution. New material development is crucial to improving the light absorption ability, photothermal conversion efficiency, and water evaporation. In this study, a separate photothermal evaporation device is proposed. The graphene oxide (GO) was combined with polyacrylonitrile (PAN) to form a composite (GO/PAN) fiber by wet spinning. GO/PAN fiber as a photothermal absorption system was further woven with cotton yarn to produce a flexible photothermal conversion device. When the device is put in fuchsin solution, it can absorb water within 20 s and be completely soaked in the solution after 25 s. When the device was irradiated by 1 standard sunlight, the water evaporation rate was 1.82 kg m−2 h−1. Under 5 or 10 standard sunlight, the water evaporation rate could reach 5.19 kg m−2 h−1 and 11.79 kg m−2 h−1, respectively. The graphene photothermal evaporation device of the invention adopts the method of interfacial evaporation here is easy to manufacture and has good flexibility. With the help of independent water transport and photothermal absorption system, the device can achieve high water absorption and photothermal properties, showing great potential for high-efficiency water desalination.