Simulated Solar Irradiation Research Articles

Synergistic Enhancement of Stability and Performance for Perovskite Solar Cells Using Fluorinated Benzoic Acids as Additives

The introduction of additives with specific functional groups is an important approach to extend the operational lifetime of perovskite solar cells (PSCs). Herein, the effect of the additives of benzoic acid (0F‐B), 4‐fluorobenzoic acid (1F‐B), and 2,3,4,5,6‐pentafluorobenzoic acid (5F‐B) on the performance and stability of MAPbI3‐based PSCs is systematically investigated. These additives can both chelate onto lead ions and form hydrogen bond with methyl ammonium ions. These combined interactions result in an increased activation energy for nucleation of perovskite crystals, thereby, increasing crystal size, reducing defect formation, improving electronic properties, as well as reducing ion migration. As a result, PSCs added with 5F‐B achieve the highest power conversion efficiency (PCE) of 20.50% with a narrow distribution compared to those PSC devices added with 1F‐B (19.25 %), 0F‐B (18.80 %), and pristine devices (18.53 %). Notably, 5F‐B‐added PSCs retain 80% of their initial PCE after ≈100‐day humidity test (at 25 °C and 50% relative humidity), 30‐day thermal stability test (at 85 °C in nitrogen environment), and 12‐day light illumination test (under continuous simulated solar radiation).

Magnetically separable Cu-Fe nanophotocatalyst with enhanced photocatalytic performance under visible-light irradiation: Optimizing the fuel type and heating approach in the synthesis process

This study aimed to examine the influence of fuel type and heating technique on the solution one-step solution combustion synthesis of CuFe2O4 spinel-type photocatalysts. The primary goal was to establish the best configuration of nanophotocatalysts with desirable characteristics, leading to improved photodegradation of dye pollutants when exposed to simulated solar radiation. Cu-spinel nanophotocatalysts were generated using a one-step combustion method involving three distinct fuels (urea, glycine, and citric acid) and two heating strategies (microwave and muffle furnace). The synthesized nanophotocatalysts were characterized through a range of tests, including XRD, FESEM, EDX, BET-BJH, FTIR, VSM, PL, DRS, and pHpzc analyses. During the simulated irradiation of sunlight, the efficacy of the Cu-spinel photocatalyst was evaluated using high-concentration Congo red, a widely used textile dye. Test results indicate that the Cu-spinel nanophotocatalyst formed utilizing glycine and microwave combustion displayed a desirable photocatalytic activity by degradation of 97 % of Congo red in 100 min. In addition, the photocatalytic efficiency of Congo red degradation was significantly enhanced compared to the other fuels and the conventional heating approach. Furthermore, CuFe(G-MW) demonstrated high stability throughout four cycles. Finally, a proposed mechanism for the degradation of Congo red using a CuFe(G-MW) nanophotocatalyst was presented.

Photodegradation of methylene blue dye using graphene oxide incorporated, post-transition metal doped zinc oxide thin films by spray pyrolysis

Photocatalytic activity of graphene oxide incorporated pure and metal doped zinc oxide thin films were studied against methylene blue dye under simulated solar irradiation. Thin films were deposited on a glass substrate using an automated spray pyrolysis technique at a temperature of 425 °C. Aluminium, gallium, and indium were the post-transition metals used for doping. Graphene oxide content in the precursor solution was fixed at 0.00375 g/l. The formation of the wurtzite structure of zinc oxide has been confirmed using structural analysis. The average crystallite size of all the thin film samples was found to be in the range of 45–55 nm. The morphology and elemental composition of the films were studied using scanning electron microscopy and energy-dispersive x-ray spectroscopy. The energy band gap of the material was determined from UV–vis-NIR spectroscopic measurements using Tauc’s plot and it is in the range of 3.25–3.28 eV. Photoluminescence spectra of the as-deposited films were recorded. Intensity of the near band emission at 395 nm was found to decrease upon metal doping, indicating a better photocatalytic property. All the films were used for heterogeneous photocatalysis and the indium doped zinc oxide thin film incorporated with graphene oxide was found to be a better catalyst with an efficiency of 94.9% for degrading methylene blue dye in 180 min.

TDA/rGO@WS with Joule heat and photothermal synergistic effect: A promising adsorption material for all–weather recovery of viscous oil spills at sea

Oil spills are a global environmental protection challenge, and traditional adsorption materials have poor effect on low temperature and high viscosity marine oil spills. This article reports composite adsorption materials TDA/rGO@WS for viscous oil spills: loaded with rGO/TDA coating on a commercial biomass wood pulp sponge (WS), achieving Joule heating, photothermal effect and hydrophobic modification. The results showed that the TDA/rGO@WS has good photothermal conversion ability and Joule heating ability, and the temperature increased to 83.7 °C and 148 °C, respectively, under simulated solar irradiation and additional voltage at room temperature. The efficiency of adsorption at a low temperature of 5 °C increased by 22.41% at 1 sun and by 51.53% at 10 V. Temperature effectively reduced the viscosity of the offshore oil spill and ensures the efficient adsorption of oil spills at low temperatures promoted. The TDA/rGO@WS also showed good hydrophobicity (WCA=129°), excellent efficiency of water–oil separation (99.53%) and good adsorption capacity (9.4–13.68 g/g) for marine fuel oils. TDA/rGO@WS effectively solves the problem of cleaning up high–viscosity oil spills from ships in winter and polar waters, and proposes a new strategy for all–weather efficient treatment of oil spills at sea.

Enhanced Anti/De-Icing Performance on Rough Surfaces Based on The Synergistic Effect of Fluorinated Resin and Embedded Graphene.

Icing negatively impacts various industrial sectors and daily life, often leading to severe safety problems and substantial economic losses. In this work, a fluorinated resin coating with embedded graphene nanoflakes is prepared using a spin-coating curing process. The results shows that the ice adhesion strength is reduced by ≈97.0% compared to the mirrored aluminum plate, and the icing time is delayed by a factor of 46.3 under simulated solar radiation power of 96mWcm-2 (1 sun) at an ambient temperature of -15°C. The superior anti/de-icing properties of the coating are mainly attributed to the synergistic effect of the fluorinated resin with a low surface energy, the rough structure of the sandblasted aluminum plate, which reduces the contact area, and the embedded graphene nanoflakes with a superior photothermal effect. Furthermore, the hydrogen bonding competition effect between the exposed-edge oxygen-containing functional groups of the embedded graphene nanoflakes and water molecules further improves the anti-icing properties. This work proposes a facile preparation method to prepare coatings with excellent anti/de-icing properties, offering significant potential for large-scale engineering applications.

Photoelectrocatalytic CO2 conversion over carbon @ silicon carbide composites

Artificial photosynthesis, which utilizes sunlight to produce value-added chemicals and fuels from CO2, is a promising strategy to storage fluctuating solar energy and to realize zero carbon cycle simultaneously. While selective C2+ production via CO2 photoelectrocatalytic conversion remains a challenge due to the sluggish C-C coupling kinetics over current artificial photosynthesis catalysts. Herein, we present a carbon @ silicon carbide (C@SiC) catalyst for ambient CO2 photoelectric reduction under simulated solar irradiation, giving a CO2 conversion rate of 487 μmol∙gcat−1∙h−1 with an ethanol selectivity of 87.8%. The optimal sp2/sp3 carbon ratio of carbon layer not only facilitates the photo-generated electrons transfer from SiC to carbon layer, but also favors the C-C coupling kinetics of key intermediates for efficient CO2 to ethanol conversion.

In-situ construction of Z-scheme 2D/2D g-C3N4/BiOBr heterojunction with enhanced photocatalytic CO2 reduction

A novel series of g-C3N4/BiOBr (CN/BOB) Z-scheme heterojunction catalysts with two-dimensional/two-dimensional (2D/2D) morphology were synthesized by an in-situ hydrolysis method for photocatalytic CO2 reduction. Without adding any sacrificial agents or co-catalysts, the optimal CN/BOB heterostructure exhibits a boosted CO generation rate of 20.1 μmol·g-1·h-1 under the simulated solar light irradiation, severally being 1.7 and 3.7 times that of pristine BiOBr and g-C3N4. The enhanced performance principally benefit from the 2D/2D microstructure and Z-scheme heterojunction of photocatalysts. The intimate contact of 2D/2D morphology signifies more transmission channels and shorter transfer interface distance of photogenerated charges. While relevant characterizations and first-principles calculations jointly demonstrate that the Z-scheme heterojunction could significantly accelerate the spatial separation and transfer of photo-induced carriers, and evidently promote the redox ability of photocatalysts. The research furnishes a novel strategy to construct a promising bismuth oxyhalide based heterojunction catalyst for the application of photocatalytic CO2 reduction.

ZnO-NRs embedded guar-gum derived CS@HNTs: A bifunctional catalyst for electrochemical detection and photocatalytic applications

Natural clay minerals and their nanocomposites are being increasingly studied for environmental remediation applications because of their abundance and unique surface properties. Halloysite nanotubes (HNTs) were modified with carbon spheres derived from guar gum through hydrothermal treatment, resulting in CS@HNTs. ZnO nanorods (ZnO-NRs) were synthesized via a sol-gel process and then loaded onto CS@HNTs, which enhanced their photocatalytic and electrochemical activities by widening their band structure and light absorption capabilities. The physicochemical and optoelectronic properties of the resulting CS@HNTs/ZnO-NRs nanocomposite was confirmed. The electrochemical detection of CPZ in the presence of CS@HNTs/ZnO/SPCE nanocomposite resulted in an excellent detection limit (LOD = 0.01 µM), sensitivity (1.917 µAµM–1 cm–2), and a wide linear range of detection (0.08–83.56 µM). Photocatalytic experiments were performed using the antibiotics tetracycline hydrochloride (TC) and CPZ under simulated solar irradiation. The degradation efficiency was 85.34 % and 83.84 %, respectively, due to the rapid charge carrier transport and reduced recombination. These findings demonstrate the excellent photocatalytic and electrocatalytic performance of the synthesized CS@HNTs/ZnO-NRs bifunctional catalyst.

Pesticide abatement using environmentally friendly nano zero valent particles as photo-Fenton catalyst

Nano-zero valent iron particles (NZVI) have been used for the pesticide pirimicarb degradation under simulated solar radiation. These particles have been synthesized by extracts from agro-industrial residues, namely vineyard and blueberry pruning, black tea and algae, so they can be labelled as “green-NZVI”. The physico-chemical properties of these green-NZVI were compared to those of NZVI synthesized with NaBH4. The usage of agro-industrial residues as reducing agent not only provided better performant NZVI but also evade the usage of harmful reagents. Indeed, this process is not only within circular economy, and environmentally friendly, but also defeats the degradation performance of the widely reported photo-Fenton process with Fe2+ catalyst. 96.5 % pirimicarb degradation was achieved under simulated solar radiation within 15 min with 0.08 mM H2O2 and 0.16 mM NZVI synthesized with black tea extract. Further, the developed process was optimized in terms of reagents concentration and natural antioxidant extract used for NZVI synthesis, which demonstrated a strong effect on pirimicarb degradation due to the differences on natural phenolic compounds present on them. The pirimicarb degradation pathway was analysed, confirming the successful pesticide degradation. In terms of H2O2 concentration, it can be reduced by its sequential addition in time. Under optimal conditions, even real effluents can be successfully degraded.

Upconversion Material-Plasmonic Metal-Semiconductor Ternary Heteronanostructures for Wide-Range Solar-to-Chemical Energy Conversion.

Harvesting full-spectrum solar energy is a critical issue for developing high-performance photocatalysts. Here, we report a hierarchical heteronanostructure consisting of upconverting, plasmonic, and semiconducting materials as a solar-to-chemical energy conversion platform that can exploit a wide range of sunlight (from ultraviolet (UV) to near-infrared). Lanthanide-doped NaYF4 nanorod-spherical Au nanocrystals-TiO2 ternary hybrid nanostructures with a well-controlled configuration and intimate contact between the constituent materials could be synthesized by a wet-chemical method. Notably, the prepared ternary hybrids exhibited high photocatalytic activity for the H2 evolution reaction under simulated solar and near-infrared light irradiation due to their broadband photoresponsivity and strong optical interaction between the constituents. Through systematic studies on the mechanism of energy transfer during the photocatalysis of the ternary hybrids, we revealed that upconverted photon energy from the upconversion domain transfers to the Au and TiO2 domains primarily through the Förster resonance energy transfer process, resulting in enhanced photocatalysis.

Fabrication of a novel MoB/BiOCl photocatalyst for losartan and Escherichia coli removal

In this work, various MoB/BiOCl (0.5–2.0% wt. MoB) photocatalysts were fabricated, characterized using X-ray diffraction, diffuse reflectance spectroscopy, scanning electron microscopy/energy dispersive spectrometer (SEM/EDS) and chronoamperometry, and their photocatalytic activity was assessed for the degradation of the persistent contaminant losartan (LOS) in aqueous solutions under simulated solar irradiation. The 0.5MoB/BiOCl catalyst exhibited the highest efficiency, achieving complete degradation of 500 μg/L LOS in less than 10 min. Interestingly, the 0.5MoB/BiOCl sample also showed remarkable efficiency under visible irradiation (>420 nm), achieving 80% removal in 30 min. The decomposition kinetics followed pseudo-first-order, while the efficiency significantly decreased under alkaline conditions. According to the scavenging experiments, both h+, O2•− and 1O2 participate in the decomposition of LOS, while the role of •OH is minor. A slight increase in degradation was observed in the presence of NaCl, and a small retardation occurred in the presence of humic acid. On the contrary, the presence of bicarbonates significantly delayed the reaction. Although significant inhibition was observed for secondary effluent, the system was capable of completely degrading LOS in less than 15 min when pH was adjusted to 3.8. The process demonstrated promising results for the simultaneous removal of E. coli and micropollutants, achieving complete LOS removal in 15 min and 99.999% inactivation of E. coli after 180 min.

Biomass Photothermal Hydrogel Based on Tea Leaves Residue for Cogeneration of Clean Water and Electricity

AbstractInterfacial solar‐driven evaporation has attracted much attention due to its high photothermal conversion efficiency. The core technology of photothermal conversion is photothermal materials, biomass photothermal materials are characterized by low cost, large specific surface area, environmental friendliness, and renewability. Discarded tea leaf residue (TLR) is harmful to the environment and has good recycling potential. In this work, a high‐performance, low‐cost, environmentally friendly solar steam generation material is fabricated by combining polyvinyl alcohol hydrogels and biomass photothermal material TLR. TheTLR hydrogel utilizes solar energy as a renewable energy source for desalination. Under 1.0 kW m−2 simulated solar irradiation, the evaporation rate is 1.35 kg m−2 h−1 and the evaporation efficiency is 93.35%. The waste heat generated during solar water evaporation can be effectively used for synergistic water‐electricity cogeneration, thus achieving an evaporation rate and voltage of 0.91 kg m−2 h−1 and 58.8 mV under 1.0 kW m−2 solar irradiation, respectively. The prepared hydrogel can also be used as a good organic dye adsorbent material, which has a broad application prospect in wastewater treatment. This method for preparing solar absorbers reduces manufacturing costs environmentally friendly and guides the potential practical application using discarded waste.

Innovative ternary bismuth oxychloride/bismuth oxide/carbon nanotubes induced excellent solar light-driven activity toward photomineralisation of diclofenac: Impact of metastable β-Bi2O3 inserted and electron-hole separation

Solar energy-utilizing photocatalysts for water purification remain essential for environmental sustainability. This report presents new concepts in bismuth oxychloride/oxide/carbon nanotubes. (BiOCl/Bi2O3/CNT) composites, synthesized through a chemical deposition method involving BiOCl in a carbon nanotube bath, followed by surface reduction/oxidation steps. The impact of nanotube ratio and calcination temperature were explored. Characterization involved ultraviolet–visible diffuse reflectance spectroscopy (UV–vis DRS), X-ray photoelectron spectroscopy (XPS), fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), elemental mapping, N2 adsorption/desorption analysis, and electrochemical impedance spectroscopy (EIS). XRD analysis revealed in-situ formation of α and β-Bi2O3 phases, rendering the composite more responsive to visible light at 200 °C. Carbon nanotubes reduced the band gap of ternary composites, yielding lower band gap energies in the visible range compared to BiOCl and Bi2O3. XPS analysis identified metallic Bi0 particles, enhancing electron mobility and charge separation. The synergy of BiOCl/Bi2O3/CNT-200 material significantly improved diclofenac degradation under solar simulator irradiation. Total organic carbon (TOC) analysis demonstrated 81 % mineralization with the BiOCl/Bi2O3/CNT-200 material. Active species trapping revealed the crucial roles of HO• radicals and h+ holes in pollutant degradation. The presence of the normally metastable β-Bi2O3 phase at 200 °C enhanced solar simulation efficiency, while carbon nanotubes acted as electron reservoirs, aided by Bi0 particles. The present study sets out an efficient composite synthesis approach for the photomineralization of complex pharmaceutical compounds.

Intermixing of MoS2 and WS2 photocatalysts toward methylene blue photodegradation.

Visible-light-driven photocatalysis using layered materials has garnered increasing attention regarding the degradation of organic dyes. Herein, transition-metal dichalcogenides MoS2 and WS2 prepared by chemical vapor deposition as well as their intermixing are evaluated for photodegradation (PD) of methylene blue under solar simulator irradiation. Our findings revealed that WS2 exhibited the highest PD efficiency of 67.6% and achieved an impressive PD rate constant of 6.1 × 10-3 min-1. Conversely, MoS2 displayed a somewhat lower PD performance of 43.5% but demonstrated remarkable stability. The intriguing result of this study relies on the synergetic effect observed when both MoS2 and WS2 are combined in a ratio of 20% of MoS2 and 80% of WS2. This precise blend resulted in an optimized PD efficiency and exceptional stability reaching 97% upon several cycles. This finding underscores the advantageous outcomes of intermixing WS2 and MoS2, shedding light on the development of an efficient and enduring photocatalyst for visible-light-driven photodegradation of methylene blue.

Selective photocatalytic C-C coupling of benzyl alcohol into hydrobenzoin using Pt-deposited CdS nanosheets passivated with cysteamine.

Achieving high selectivity towards hydrobenzoin (HB) from photocatalytic carbon-carbon (C-C) coupling reaction of benzyl alcohol (BzOH) remains a challenge due to side competing reactions and subsequent conversions of HB into its derivatives. In this study, we have developed a high-performance CdS-based photocatalyst for synthesizing HB with precisely controlled surface properties and structure, achieving high selectivity for HB synthesis. We employed strategies such as cysteamine passivation and Pt deposition to address issues related to photogenerated charge trapping and recombination, thereby enhancing the photocatalytic capability of CdS. With optimized Pt/CdS NSs as the photocatalyst, we investigated the impact of the Pt/CdS heterostructure on intermediate reactions, which in turn altered product selectivity. Specifically, excessive Pt suppresses the electron-induced benzaldehyde-to-intermediate reaction by consuming electrons for the competing hydrogen evolution reaction (HER), leading to high selectivity toward benzaldehyde. In contrast, bare CdS without Pt suffers from insufficient charge supply for BzOH conversion due to the charge recombination issue, which promotes the subsequent conversion of HB to its derivatives. Notably, when Pt is precisely loaded to avoid dominant HER competition, the overall reaction rate increases, maintaining high selectivity towards HB and ensuring faster conversion of BzOH to HB rather than subsequent conversions of HB into its derivatives, thereby maximizing the HB yield. Subsequently, we have developed a photocatalyst that achieves a 93.4% conversion of 0.24 mmol BzOH with 85.3% selectivity toward HB under solar simulator irradiation (AM 1.5G). This work is expected to offer instructive guidance on rationally designing the photocatalyst for efficient C-C coupling reactions.

Plasma-induced N doping and carbon vacancies in a self-supporting 3C-SiC photoanode for efficient photoelectrochemical water oxidation

We report that a plasma-induced self-supporting 3C-SiC photoanode with N doping and carbon vacancies demonstrates high photocurrent density and stability for photoelectrochemical water oxidation in alkaline solution under simulated solar irradiation.

A novel dual S-scheme Co9S8/MnCdS/Co3O4 heterojunction for photocatalytic hydrogen evolution under visible light irradiation.

Rational design and synthesis of a unique heterojunction photocatalyst structure is an important strategy to enhance its performance and structural stability. Herein, Co9S8/MnCdS/Co3O4 photocatalysts with double S-scheme heterojunctions were successfully prepared by coupling Co9S8 and Co3O4 sheet structures with n-type MnCdS nanoparticles through a simple solvothermal and mechanical mixing method. The construction of the dual S-scheme heterostructure offers the possibility to expand the light absorption range, extend the carrier lifetime and maximise the redox capacity. In addition, the mechanism of charge transfer and the reason for the improvement of photocatalytic activity were explored through photoelectrochemical characterization. The lamellar structures of Co9S8 and Co3O4 not only provide excellent dispersion and slow down the agglomeration of MnCdS nanoparticles, but also promote charge transfer, which improves the photocatalytic hydrogen production effect. Under simulated solar irradiation, the evolution rate of H2 after 5 h was as high as 46.44 μmol, which was 3.49 and 1.49 times higher than those of pristine MnCdS and MnCdS/Co3O4, respectively. Meanwhile, it has good stability under 20 h irradiation. This work demonstrates a novel idea for the rational design of double S-scheme photocatalysts with efficient space separation.

Efficiently Photocatalytic Activities of Novel Metal-free g-C3N4 Under Simulated Solar Irradiation: Removal Efficiency, Influence Factors, and Reaction Mechanism

Efficiently Photocatalytic Activities of Novel Metal-free g-C3N4 Under Simulated Solar Irradiation: Removal Efficiency, Influence Factors, and Reaction Mechanism

Photo-aging of brominated epoxy microplastics in water under simulated solar irradiation.

Microplastics have become an increasingly concerning pollutant in aquatic environments, and photodegradation is their main degradation pathway in water. Gaining insight into the transformation process of microplastics will enhance our understanding of their behavior and destiny in natural environments. This paper studied the aging process of BER microplastics in aquatic environments under simulated sunlight and investigated the changes in the physical and chemical properties of microplastics and the changes in the leachate. During the photodegradation process, BER-MPs underwent extensive oxidation and reduction in particle size, and the originally smooth surface developed numerous voids, accompanied by yellowing. Introduction of O atoms in the molecular chains increased their hydrophilicity, resulting in the polymer chains breaking away from the plastic particles and dissolving in water. Also, once BER was excited by light, environmentally persistent free radicals are produced on its surface. Moreover, the breaking of C-Br bonds occurred during the photodegradation process of BER-MPs, which suggested that tetrabromobisphenol A would be transformed during the photoaging process of BER even if it was covalently bound to BER.

TiO2 nanopowder and nanofilm catalysts in the disinfection and mineralization of S. aureus with solar-simulated radiation

TiO2 films photo-catalyze S. aureus rupture and mineralization of resulting organic materials.