Irradiation Intensity Research Articles

Use of CdZnTe Quasi-Hemispherical Detectors under the Impact of Low Temperatures and High-Gamma Radiation Fluxes.

This article discusses the possibilities and limitations of CdZnTe (CZT) quasi-hemispherical detectors operating over a wide temperature range and at high-gamma radiation fluxes. The results of the negative influence of low- and high-operating temperatures, as well as high-radiation fluxes on spectrometric characteristics of CZT detectors and possible ways to eliminate performance deterioration, are presented. The impact of infrared (IR) illumination parameters, such as wavelength and irradiation intensity on the spectroscopy performance of detectors, was investigated. A correctly chosen IR illumination wavelength and intensity were shown to significantly improve the energy resolution of CZT quasi-hemispherical detectors, allowing their stable operation in high-gamma radiation fluxes and extend the operating temperature range toward low temperatures. The influences of bias voltage values and temperatures on the quasi-hemispherical CZT detectors' operating ability at high-gamma radiation fluxes were studied.

Full-Wood Utilization Strategy toward a Directional Luminescent Solar Concentrator.

Luminescent solar concentrators (LSCs) have proven to be highly effective in enhancing the conversion efficiency of photovoltaic (PV) cells. However, the traditional LSCs always suffer from self-absorption and escape the losses of luminescence. To these challenges, this study presents an ingenious all-wood-based LSC (W-LSC) with directional light-concentrating capabilities. By converting lignin into fluorescent carbon quantum dots (CQDs) and integrating them into transparent cellulose channels in delignified wood, we achieved efficient directional luminescence transmission in the W-LSC is achieved. The synthesized lignin-based CQDs (L-CQDs) exhibited a large Stokes shift (0.63 eV) and a bright yellow emission (540 nm). The prepared W-LSC possessed an external optical efficiency (ηopt) along the longitudinal (L) direction of 4.60% under a low irradiation intensity (40 mW·cm-2). Besides, contributed to the low thermal conductivity (0.300 W·m-1·K-1) of wood, the W-LSC maintained an ηopt of 4.03% at a temperature of 65 °C. Furthermore, the W-LSC demonstrated high tensile strength (424 MPa) and light transmission (85%). By leveraging the advantages of wood, this approach provides a different solution for enhancing solar energy utilization and advancing sustainable building.

Employing controlled periodic illumination in identifying limiting factors of heterogeneous catalytic processes: A case study of photocatalytic generation of H2O2 and H2

Semiconductor photocatalysis is a versatile process that has been utilised in a wide range of applications from water treatment to sustainable energy generation and storage. In a heterogeneous photocatalytic reaction, identifying the limiting factor in a reaction is crucial in optimising operating parameters such as catalyst loading or irradiation intensity. With the application of Controlled Periodic Illumination (CPI), it is possible to control the intensity of photons entering the system. In this paper, two processes were evaluated and monitored by employing CPI to identify limiting factors: photocatalytic generation of H2O2 and H2. The relationship between catalyst loading and light intensity on H2/H2O2 generation constant rate was explored using CPI. In photocatalytic generation of H2O2, two commercial catalysts, TiO2 and ZnO were used under identical experimental conditions and the limiting factors on them differed. The effect of CPI varied greatly between both catalysts with TiO2 demonstrating that up to 50% less light is required to achieve comparable H2O2 formation rates at lower catalyst loadings (0.1 g L−1). In contrast, for ZnO photocatalysis, the CPI experiments highlighted the impact of adsorbed O2 levels, catalyst loading, and light intensity on H2O2 yields. The H2O2 formation rate constant plateaued beyond a duty cycle of 0.6 regardless of the tested catalyst loading. For photocatalytic generation of H2 on Pt/TiO2 from glucose, the generation rate constant increased linearly at low duty cycles and plateaued with different catalyst loading, which helped to identify different limiting factors for each condition. Therefore, exploring H2O2 and H2 generation via CPI is reported for the first time and the results show the importance of monitoring the interdependency of photocatalytic parameters and prove the validity of CPI on determining the limiting factor.

Thermal damage analysis of sub-surface soft tissue sarcoma for indocyanine green mediated photothermal cancer therapy

Photothermal therapy is a minimal invasive technique to treat tumors situated near the skin or other light accessible organs. Here, a photothermal agent is delivered to tumor either intratumorally or intravenously and the tumor is irradiated with near infrared (NIR) radiation to generate heat for thermal damage of tumor. In this paper, thermal damage of soft tissue sarcoma, a type of sub-surface forearm tumor, is evaluated for photothermal therapy using numerical simulations. Indocyanine green (ICG) is used as photothermal agent and the effect of various spatial distributions and doses of ICG for sub surface tumors located at various depths (3–6 mm) were investigated. Further, numerical simulation is validated experimentally through tumor-tissue mimicking phantoms. Computations were performed in MATLAB software using Lattice Boltzmann method and validated through experiments using tumor-tissue mimicking phantoms. Results show that the thermal damage region (damage parameter (Ω) of magnitude 4.6) was enlarged on increasing the concentration of ICG while it got shrunk for the deeper tumors. Computations reveal that ICG concentration of 50 μg/mL is optimum, for intravenous distribution, for photothermal therapy with minimal damage to surrounding tissue. It is found that irradiation duration of more than 900 s is required to achieve the complete damage of tumor. For the case of deeper tumors, about 1200 s of exposure is required, at irradiation intensity of 0.25 W/cm2. This study provides a numerical approach to determine therapeutic parameters and demonstrates the thermal damage for subsurface tumors through ICG mediated photothermal therapy by proper selection of therapeutic parameters.

Improved spectral mismatch and performance of a phosphor-converted light-emitting diode solar simulator

<span lang="EN-US">A phosphor-converted light-emitting diode (LED) solar simulator is an illuminance device that produced irradiance intensity and spectral close to the sunlight. It is determined as spectral mismatch, non-uniformity of irradiance, and temporal instability. This paper has improved the LED solar simulator (LSS) system to have a spectral distribution consistent with the AM1.5G spectrum at 100%. It was developed as a new prototype to have the AAA class spectral characteristics, time instability, and inconsistency according to IEC 60904-9. The results showed that an optimal approach was to use phosphor-converted natural white LED (pc-nWLED), combining a monochromatic near-infrared (NIR) (730, 800, 850, 940, and 1,000 nm) as well as the proposed LSS system capable of generating 1,000 W/m<sup>2</sup> irradiation over the test plane of 125×125 mm and operated continuously in a constant temperature LED state for at least 2 hours, therefore suitable for demonstration of solar cell features under standard test condition (STC) in the laboratory.</span>

Pool-boiling enhancement on periodic micro/nano ripple-structured surfaces fabricated by femtosecond laser

A study was conducted on whether periodic micro/nano ripple structures generated on metal surfaces using femtosecond laser processing could improve pool boiling heat transfer. Depending on the laser irradiation conditions on the metal surface, a surface structure with different geometrical characteristics is created. Changes in sample surface morphology caused by the laser irradiation intensity are examined using scanning electron microscopy and confocal laser microscopy. Pool boiling tests are conducted to compare three laser irradiation conditions fabricated samples and the bare copper surface. The working fluid is deionized water. The pool boiling curves of each sample surface were compared with each other. Visualization of bubble nucleation is performed using a high-speed camera. The superheat, bubble departure diameter, and bubble growth period of each sample are measured and compared at the onset of nucleate boiling (ONB). The most efficient periodic micro/nano ripple-structured surface reduces the superheat at the ONB by 6.13 °C in comparison with that at the bare Cu surface. The enhanced surface structure reduced the bubble departure diameter and renewal period by 60.5% and 55.6% in comparison with that of the smooth surface. Further, the structured surface showed 178.5% enhancement in heat transfer coefficient and 39.1% in critical heat flux, respectively. Thus, the combination of increased nucleate site density, high nucleation site activation, and a wicking effect in the periodic micro/nano ripple structure significantly improves the pool boiling heat transfer.

Experimental performance of air-type BIPVT systems under different climate conditions

In this study, the thermal/electrical performance of an air-type BIPVT system was investigated under complex environmental conditions by constructing a movable experimental system using copper indium gallium selenide photovoltaic modules as photovoltaic units. Experimental studies were conducted in four regions with different latitudes (Sanya, Hulunbeier, Dongtai, and Beijing) to determine the effect of the quantitative relationships between the ventilation flow rate and climate conditions on the photothermal and photovoltaic performance of the system. Taking Sanya as an example, the results show that the thermal energy and power generation are both positively correlated with irradiation intensity, and that increasing the flow rate can effectively increase the thermal energy. By increasing the ventilation flow rate from 0.4 m/s to 2.2 m/s, the average thermal efficiency throughout the day could be increased from 23.0% to 51.8%, but the electrical efficiency only increased by approximately 3.5%. A comparison of the thermal/electrical performance in different geographic regions revealed that the thermal efficiency varies widely (by as much as 8%) at high flow rates, whereas the variation in relative power generation is small. The results can guide the design of air-type BIPVT systems.

Solar Photo-Voltaic and thermal (PVT) system facilitated with novel coaxial condensing heat pipe (CCHP): Thermo hydrodynamic modelling and parametric optimization for overall operation performance

Heat pipes offer tremendous potential for utilization in the energy and construction industries due to their excellent heat transmission efficiency. The current study involved the development of a theoretical model for thermal transport in a coaxial condensing heat pipe (CCHP) connected with solar photovoltaic and thermal (PVT) systems. Subsequently, parameter studies were conducted to analyze their impact on system performance, including irradiation intensity, surrounding temperature, inlet temperature, mass flow rate and PV coverage factor. In addition, temperature variation, thermal and electrical conversion capabilities of the CCHP/PVT system on typical days were discussed utilizing meteorological conditions in Wuhan city as inputs for the analysis. Our findings showed that the morning is when thermal efficiency is at its highest across the seasons, and it remained between 50% and 55%. Compared to natural cooling and conventional heat pipe cooling, the CCHP/PVT system reduced the temperature of the PV panels by approximately 30.3% and 16.3%, respectively. The proposed CCHP/PVT system has a respectively 14.4% and 5.2% enhancement in thermal and electrical efficiencies in comparison with those conventional heat pipes. Here, theoretical results agree well with former published ones, with average errors of no more than 10%. Our parametric investigations were then put into practice to assess the overall performance and to serve as a theoretical foundation for later development. It was really beneficial to boost the efficiency of solar energy utilization in the Yangtze River, China, where solar potentials were relatively poor than north western China.

Techno-economic analysis and optimization of green hydrogen production and liquefaction with metal hydride storage

A techno-economic analysis and three-objective optimization are reported for a system that uses a renewable energy source (RES) for hydrogen production and liquefaction in which all the produced hydrogen enters the liquefaction cycle. The system works in three phases; hydrogen liquefaction, hydrogen storage and fuel cell power generation. Every second, the mass of produced hydrogen from the electrolyzer is calculated and immediately injected into the liquefaction cycle. This happens for 3600 s during each hour and for 12 h during the day. To reduce the execution time and increase the accuracy, six different artificial neural network (ANN) models have been used, which are optimized using genetic algorithm (GA). Decision variables for optimization include solar irradiation intensity, ambient temperature, heat exchanger efficiency, and isothermal compressor output pressure. The objective functions are chosen to be total exergy efficiency, liquefaction efficiency, and total cost rate, and the optimal values of the objective functions are found to be 19.3%, 19.8%, and 10.6 $/hr, respectively. The objective functions are illustrated in terms of daily time, as well as decision variables. Also, the effect of liquefaction efficiency and specific work consumption on liquefaction cycle parameters and electrolyzer temperature have been investigated. The results show that in the range of compressor output pressure between 5 and 15 MPa, for every n % increase in heat exchanger efficiency, the liquefaction efficiency increases by (n/2) % and the amount of liquid hydrogen production at steady-state becomes 0.162 kg/h. It is also found that if the storage system is turned off and all the produced power is given to the liquefaction system, the mass of liquefied hydrogen will increase by 17% at the end of the day.

Effects of plasma treatment on germination and biochemical content of chicory (sonchus oleraceus l.)

An experiment was conducted to explore the changes of germination rate, protein and vitamin C content in the seeds and the chlorophyll content of the seedlings under different irradiation time and intensity. Experiments showed that plasma treatment of chicory seeds promoted the germination and biological content of bitter seeds in 100-300W, 5-15s, and the germination rate was relatively higher under 200W conditions, the content of vitamin C and protein in seeds was relatively higher under 300W conditions. Bangladesh J. Bot. 52(2): 445-450, 2023 (June) Special

Effects of plasma treatment on germination and biochemical content of chicory (sonchus oleraceus l.)

An experiment was conducted to explore the changes of germination rate, protein and vitamin C content in the seeds and the chlorophyll content of the seedlings under different irradiation time and intensity. Experiments showed that plasma treatment of chicory seeds promoted the germination and biological content of bitter seeds in 100-300W, 5-15s, and the germination rate was relatively higher under 200W conditions, the content of vitamin C and protein in seeds was relatively higher under 300W conditions. Bangladesh J. Bot. 52(2): 445-450, 2023 (June) Special

Fundamental understanding of irradiation intensity and other process parameters on photocatalytic degradation of phenol in hollow fiber mixed matrix membrane

Lack of comprehensive general theoretical model on photocatalytic mixed-matrix-membrane (PMMM) makes its practical application infeasible. The dynamic process involves bulk and porous fluid-flow; bulk convection–diffusion, interfacial adsorptive-reactive mass transport. All-inclusive first-principle based two-dimensional transient model with the continuity, momentum transport and convective-diffusive-adsorption-reaction equations are solved numerically. Experimental validation was taken up for phenol removal from synthetic solution using PMMM hollow fibres with titanium-di-oxide nanoparticle. The validated model were used to predict the performance at various light intensity (I) and feed concentrations (c0) in long-term successfully for three different cases of PMMMs. For the chosen case of PMMM, minimum I and maximum transmembrane pressure (TMP) with variable c0 for safe permeate were determined. The ‘safe operating conditions’ is the favourable operating conditions that generates permeate stream featuring a contaminant concentration under the safe discharge limit for a substantial period of time. For futuristic PMMM, a thorough parameter study was undertaken. The optimum TMP for minimum energy cost for scale-up were calculated interrelating with cross flow rates. Volume run-down was determined at safe operating conditions. This comprehensive theoretical framework can be implemented as groundwork to design present or futuristic hollow fiber PMMMs.

Understanding the Mechanism of Light-Induced Age-Related Decrease in Melanin Concentration in Retinal Pigment Epithelium Cells.

It is known that during the process of aging, there is a significant decrease in the number of melanosomes in the retinal pigment epithelium (RPE) cells in the human eye. Melanosomes act as screening pigments in RPE cells and are fundamentally important for protection against the free radicals generated by light. A loss or change in the quality of melanin in melanosomes can lead to the development of senile pathologies and aggravation in the development of various retinal diseases. We have previously shown that the interaction between melanin melanosomes and superoxide radicals results in oxidative degradation with the formation of water-soluble fluorescent products. In the present study, we show, using fluorescence analysis, HPLC, and mass spectrometry, that visible light irradiation on melanolipofuscin granules isolated from RPE cells in the human eye results in the formation of water-soluble fluorescent products from oxidative degradation of melanin, which was in contrast to lipofuscin granules and melanosomes irradiation. The formation of these products occurs as a result of the oxidative degradation of melanin by superoxide radicals, which are generated by the lipofuscin part of the melanolipofuscin granule. We identified these products both in the composition of melanolipofuscin granules irradiated with visible light and in the composition of melanosomes that were not irradiated but were, instead, oxidized by superoxide radicals. In the melanolipofuscin granules irradiated by visible light, ions that could be associated with melanin oxidative degradation products were identified by applying the principal component analysis of the time-of-flight secondary ion mass spectrometry (ToF-SIMS) data. Degradation of the intact melanosomes by visible light is also possible; however, this requires significantly higher irradiation intensities than for melanolipofuscin granules. It is concluded that the decrease in the concentration of melanin in RPE cells in the human eye with age is due to its oxidative degradation by reactive oxygen species generated by lipofuscin, as part of the melanolipofuscin granules, under the action of light.

Mesoporous carbon spheres modified polyurethane sponge/phase change material composites: Photothermal conversion, thermal storage and efficient recovery of high-viscosity crude oil

Efficient recovery of crude oil spills is still a great challenge for worldwide due to its high-viscosity and low-fluidity. Although the application of solar-heated absorbents in accelerating crude oil recovery has achieved significant progress, solar irradiation intensity is greatly dependent on time, location and weather conditions, which greatly restrict their practical application. In order to solve this problem, a novel phase change material (PCM)-included polyurethane (PU) sponge with simultaneous solar energy conversion and storage capacity was prepared and used for crude oil removal from spill. As the oil adsorption material matrix, the polyurethane (PU) sponge was combined with mesoporous carbon spheres (MCS) first and further encapsulated myristic acid (MA) as latent heat storage material to obtain PU/MCS/MA composite PCMs. The high latent heat value (129.27 J g−1), large porosity, excellent solar-thermal conversion and storage capacity make PU/MCS/MA show remarkable in-situ oil viscosity reduction and it can absorb about 1.08 g cm−3 of crude oil under sunlight. Importantly, due to the encapsulation of MA, PU/MCS/MA can achieve efficient thermal storage to reduce the viscosity of crude oil via releasing latent heat at special circumstances. This study provided a potential strategy for the efficient utilization of clean energy and crude oil spills pollution treatment.

Singlet oxygen-induced alteration of bacteria associated with phytodetritus: Effect of irradiance.

Contrasting irradiation of senescent cells of the diatom Thalassiosira sp. in association with the bacterium Pseudomonas stutzeri showed the effect of intensity of irradiance on the transfer of singlet oxygen (1 O2 ) to bacteria attached to phytoplanktonic cells. Under low irradiances, 1 O2 is produced slowly, favors the oxidation of algal unsaturated lipids (photodynamic effect), and limits 1 O2 transfer to attached bacteria. However, high irradiances induce a rapid and intense production of 1 O2 , which diffuses out of the chloroplasts and easily reaches the attached bacteria, where it efficiently oxidizes their unsaturated membrane components. Analysis of numerous sinking particle samples collected in different regions of the Canadian Arctic showed that the photooxidation state of attached bacteria increased from ice-covered areas to open water, in agreement with in vitro results. Photooxidation of bacteria appeared to be particularly intense in sea ice, where the sympagic algae-bacteria association is maintained at relatively high irradiances for long periods of time.

A calculation method for the view factor between a wall and other feature surfaces under the influence of spherical canopy

Radiation heat transfer is one of the main modes of heat exchange for building exterior walls. When a tree is added to the site, the view factor (VF) between the exterior wall and surrounding surfaces, such as walls and floors, is affected, thus significantly impacting the radiation heat transfer of the exterior wall. In order to quantitatively analyze the impact of trees with spherical canopy on the radiation heat transfer process of exterior walls, a method for calculating the VF between the exterior wall and adjacent surfaces using the optical projection simulation method was proposed. The VF between the wall surface and the adjacent surface, as well as the visibility between the wall and ground surfaces when obstructed by the spherical canopy, can be approximately calculated. Finally, the VFs calculated are used to establish the radiation heat equations according to network diagram for radiation heat transfer. By comparing theoretical values with the measured values of irradiation intensity and radiosity intensity, it was found that the error rate of the optical projection simulation method does not exceed 3%. This method can be used to further study the effects of factors such as canopy's diameter, wall-canopy distance, and planting orientation on the disturbance of radiation heat transfer of building exterior walls.

Interaction Study of Energetic Protons and Electrons with the Vacuum Ultra Violet Source used in the Complex Irradiation Facility

Context: One important factor to be considered for space missions is the radiation environment. It is composed of energetic particles, such as protons, electrons and ions, and electromagnetic radiation, photons ranging from Vacuum Ultra Violet (VUV) to Far Infrared (FIR). Each of these radiation sources have an unique energy spectrum that further depends on the location inside the solar system, e. g. Earth orbits or interplanetary space.For material qualification and material engineering, individual irradiation is considered and their effects are superimposed. However, effects occurring when two and more radiation types simultaneously are present have barely been investigated yet. Further complexity is added, when additional interactions take place due to laboratory hardware. Aims: This publication reports on the efforts made to analyse and measure the interaction of a VUV and corpuscular radiation sources. The aim is to quantify the deviations due to interactions and conclude consequences for the simultaneous operation of these radiation sources. Methods: In order to quantify the effects, the Complex Irradiation Facility (CIF), located at the DLR Bremen has been used. It connects proton and electron accelerators together with VUV and UV light sources to an ultra high vacuum chamber. The corpuscular and VUV radiation sources have been operated simultaneously. The reaction of the operation parameters, such as current measured with Faraday Cups (FC) has been tracked and post-processed. Results: It has been discovered, that protons considerably interact with the gas mixture used to operate the VUV source. This interaction decreases for higher beam intensities of the corpuscular irradiation. It was found, that this is likely due to protons ionizing gas atoms which are then measured by the FC as current. For electrons, this phenomena was not observed due to their smaller stopping power. The discovery restricts the acceleration factor of the CIF for proton together with VUV irradiation, but does not necessarily limit the range of application of the CIF depending on the requirements of the material and/or qualification test. Energy range of electrons stays unrestricted.

Modern DC–DC Power Converter Topologies and Hybrid Control Strategies for Maximum Power Output in Sustainable Nanogrids and Picogrids—A Comprehensive Survey

Sustainable energy exhibited immense growth in the last few years. As compared to other sustainable sources, solar power is proved to be the most feasible source due to some unanticipated characteristics, such as being clean, noiseless, ecofriendly, etc. The output from the solar power is entirely unpredictable since solar power generation is dependent on the intensity of solar irradiation and solar panel temperature. Further, these parameters are weather dependent and thus intermittent in nature. To conquer intermittency, power converters play an important role in solar power generation. Generally, photovoltaic systems will eventually suffer from a decrease in energy conversion efficiency along with improper stability and intermittent properties. As a result, the maximum power point tracking (MPPT) algorithm must be incorporated to cultivate maximum power from solar power. To make solar power generation reliable, a proper control technique must be added to the DC–DC power converter topologies. Furthermore, this study reviewed the progress of the maximum power point tracking algorithm and included an in-depth discussion on modern and both unidirectional and bidirectional DC–DC power converter topologies for harvesting electric power. Lastly, for the reliability and continuity of the power demand and to allow for distributed generation, this article also established the possibility of integrating solar PV systems into nanogrids and picogrids in a sustainable environment. The outcome of this comprehensive survey would be of strong interest to the researchers, technologists, and the industry in the relevant field to carry out future research.

Swirling jet impingements for thermal management of high concentrator solar cells using nanofluids

Large intensity of irradiance in high concentrator solar cells leads to extremely high temperatures causing an adverse effect on the performance of solar cells. Efficient cooling systems are crucial for the optimal performance of high concentrator cells, which are typically required to operate within a prescribed temperature range (⁓ 110 °C). The implementation of effective cooling strategies poses a significant challenge for High Concentrator Photovoltaic Thermal (HCPV/T) hybrid systems to ensure sustained performance and longevity of the modules. This study proposes a novel method for the thermal management of High Concentrator Solar Cells (HCSC) using swirling nanofluid jets impinging on a heat sink. The study applies RANS (Reynolds-Averaged Navier-Stokes) method with the SST k-ω turbulence model and energy equation to resolve a conjugate heat transfer analysis for three different flow ratios: Qr = 0, Qr = 0.5 and Qr = 1 and two water-based nanofluids: Al2O3-Water and CuO-Water. The numerical results demonstrate a significant decrease in cell temperatures, reaching as low as 71 °C. At a mass flow rate of 50 g/min, the use of Al2O3-Water nanofluid increases the overall electrical efficiency by a maximum of 39.43%. In contrast, a minimum electrical efficiency of 39% for CuO-Water nanofluid is obtained for a lower mass flow rate (25 g/min). Al2O3-Water nanofluid yielded a maximum PEC (Performance Evaluation Criteria) of 116%, while CuO-Water nanofluid yielded about 113%. In addition, an increase of the mass flow rate results in an improvement of temperature uniformity, as demonstrated by a reduction of temperature variation from 6.8 to 5.2. These results suggest that the use of nanofluids is promising. The proposed swirling jet impinging on a heat sink in combination with nanofluid provides an effective cooling technique for HCSC, thereby potentially contributing to the improvement of the cell's performance and longevity.

Light-driven photothermocatalytic performance of the Pt/Co3O4 catalyst for toluene oxidation

Light-driven photothermocatalytic oxidation is a promising method for the elimination of volatile organic compounds (VOCs). The Co3O4, 0.46 Pt/Co3O4 and 0.97 Pt/Co3O4 catalysts were fabricated via the simple molten salt and incipient wetness impregnation method. Compared with Co3O4 and 0.46 Pt/Co3O4, the 0.97 Pt/Co3O4 catalyst showed higher photothermocatalytic performance for toluene oxidation under simulated solar irradiation intensity of 900 ​mW ​cm−2, with the toluene conversion and CO2 yield being up to 98.3 % and 96.0 %, respectively. The better activity was ascribed to its outstanding strong light absorption and low temperature reducibility. Meanwhile, 0.97 Pt/Co3O4 also exhibited an excellent photothermocatalytic stability and H2O resistance. The Vis−IR light played a key role in the photothermocatalytic oxidation of toluene in the whole solar spectrum. This work benefited the synthesis of catalysts with good photothermocatalytic activity for environment friendly treatment of VOCs.