Light-harvesting Capacity Research Articles

COF@CNT based fiber gable Roof-Shaped solar evaporators for efficient Salt-Rejecting desalination and agricultural applications

Covalent organic frameworks (COFs) hold promise for solar-driven steam generation (SSG) due to their structural richness and flexibility. However, the application of certain COFs is limited by their light-harvesting capacity and solar-thermal conversion efficiency due to energy loss from charge radiative relaxation. A donor–acceptor system (COF@CNT) exhibiting 97 % light absorption efficiency across 250–2500 nm was synthesized to address these issues. The synergistic effect of enhanced charge transfer and suppressed radiative relaxation in the COF@CNT material significantly improved its solar-thermal conversion efficiency, achieving a temperature increase of approximately 70 °C under 1 sun illumination. Furthermore, the scalable COF@CNT/PAN (CCP) fiber membrane, combined with a gable roof-shaped support referred to as MGR, achieved an evaporation rate of 1.78 kg m−2h−1 and an energy efficiency of 98 % in 10 wt% saline water. Facilitated by ultrafast water transport and Marangoni flow, the MGR evaporator effectively rejected salt and maintained stable performance over 14 days in 10 wt% salt solution, producing water that met the quality standards for plant growth. This study introduces an in situ chemical synthesis method for developing advanced photothermal evaporation materials, offering significant potential for efficient seawater desalination and self-sufficient marine aquaculture systems.

Self-enhanced photoelectrocatalytic removal of Ni-organic complex and Ni recovery by the in-situ forming anodic Ni deposit: P-n junction-driven photocatalytic oxidation and chemical oxidation

The aim of this study was to propose a novel strategy for self-enhanced Ni-organic complex decomplexation and simultaneous Ni recovery based on photoanodic Ni deposition using photoelectrocatalytic (PEC) system. Compared to the conventional PEC process, the deposition of Ni2+ on TiO2 nanorod arrays photoanode led to a 30 % increase in decomplexation efficiency for Ni-ethylenediaminetetraacetic acid (Ni-EDTA). The Ni-EDTA removal rate reached 81.0 ± 0.9 %, and the Ni recovery rate achieved 58.2 ± 0.1 % under a bicarbonate buffer condition at pH 8.5 and a current density of 0.5 mA/cm2. The anodic high-valent Ni deposit can mediate chemical oxidation of Ni-EDTA in the PEC process, which has significant potential for deep mineralization of Ni-EDTA. The formation of Ni-deposited TiO2 film significantly improved PEC activity of photoanode, as revealed by the facilitated interfacial charge transfer, suppressed charge recombination, and improved light harvesting capacity. Moreover, the photocatalytic film that exhibited p-n heterojunction characteristics associated with the accelerated electron-hole pair separation and downward shift in energy bands of TiO2, stimulated ‧OH generation during PEC process, playing a pivotal role in Ni-EDTA decomplexation. Our results highlight the potential of using anodic Ni deposition for the efficient PEC treatment of plating wastewater containing Ni-organic complex.

Highly Stable Near-Infrared II Luminescent Diradicaloids for Cancer Phototheranostics.

Near-infrared II (NIR-II) phototheranostic agents have become prominent agents for the early diagnosis and precise treatment of cancer. Organic open-shell diradicaloids with distinct structure and narrow band gap are promising candidates for phototherapeutic agents due to their strong spin-coupling effect and NIR light-harvesting capacity. However, achieving stable and efficient NIR-II luminescent diradicaloids is crucial yet rather challenging considering their high chemical reactivity and self-absorption. Herein, two highly stable NIR-II luminescent diradicaloids, 2PhNVDPP and PhNVDPP, were successfully fabricated by employing an acceptor planarization/π-conjugation extension and donor rotation strategy. After encapsulation into water-dispersible nanoparticles (NPs), 2PhNVDPP NPs exhibit NIR-II luminescence, high PCE of 53%, and improved photo/heat stability. In vivo experiments with 2PhNVDPP NPs demonstrated the clear visualization of blood vessels and tumors, as well as the successful NIR-II imaging-guided photothermal ablation of tumors. This study not only develops a pioneering stable diradicaloid phototherapeutic agent with NIR-II luminescence but also provides a unique perspective for the effectiveness of multimodal anticancer therapy.

Photothermal-assisted S-scheme heterojunction of NiPS3 nanosheets modified ZnIn2S4 microspheres for promoting photocatalytic hydrogen evolution

Exploring high-efficiency photocatalysts for solar hydrogen (H2) generation through water splitting is of great significance for addressing both energy shortage and environmental contamination. In this work, a facile self-assembly strategy was developed to couple NiPS3 nanosheets (NPS NSs) with ZnIn2S4 (ZIS) microspheres to synthesize NPS NSs/ZIS (NPS/ZIS) composites, featuring a characteristic of S-scheme charge transfer mechanism. The NPS/ZIS composites possess broad-spectrum light absorption property, improved photothermal effect and efficient charge transfer, showcasing exceptional solar-to-chemical energy conversion capability for visible-light-driven photocatalytic hydrogen evolution (PHE). The photothermal effect derived from NPS NSs loading can facilitate charge carrier transfer across the interfaces and surface reaction kinetics. By carefully adjusting the mass ratio of NPS NSs, the optimized 4-NPS/ZIS exhibits excellent stability and significantly improved PHE activity (1827.6 μmol⋅g−1⋅h−1) in water, which is 18.4 times higher than that of bare ZIS (99.4 μmol⋅g−1⋅h−1). Furthermore, the 4-NPS/ZIS also shows the high PHE efficiency of 312.2 μmol⋅g−1⋅h−1 in seawater. Diverse characterization results reveal that the remarkably enhanced PHE performance primarily arises from the synergistic effect of S-scheme heterostructure, heightened light harvesting capacity, and enhanced photothermal effect. On the basis of density functional theory (DFT) simulations and experimental verifications, a possible PHE mechanism via the S-scheme heterojunction with photothermal assistance in NPS/ZIS is proposed. This study serves as inspiration for the development of novel photothermal-assisted S-scheme photocatalysts, paving the way for efficient and sustainable green energy production.

Holobiont Traits Shape Climate Change Responses in Cryptic Coral Lineages.

As ocean warming threatens reefs worldwide, identifying corals with adaptations to higher temperatures is critical for conservation. Genetically distinct but morphologically similar (i.e. cryptic) coral populations can be specialized to extreme habitats and thrive under stressful conditions. These corals often associate with locally beneficial microbiota (Symbiodiniaceae photobionts and bacteria), obscuring the main drivers of thermal tolerance. Here, we leverage a holobiont (massive Porites) with high fidelity for C15 photobionts to investigate adaptive variation across classic ("typical" conditions) and extreme reefs characterized by higher temperatures and light attenuation. We uncovered three cryptic lineages that exhibit limited micro-morphological variation; one lineage dominated classic reefs (L1), one had more even distributions (L2), and a third was restricted to extreme reefs (L3). L1 and L2 were more closely related to populations ~4300 km away, suggesting that some lineages are widespread. All corals harbored Cladocopium C15 photobionts; L1 and L2 shared a photobiont pool that differed in composition between reef types, yet L3 mostly harbored unique photobiont strains not found in the other lineages. Assemblages of bacterial partners differed among reef types in lineage-specific ways, suggesting that lineages employ distinct microbiome regulation strategies. Analysis of light-harvesting capacity and thermal tolerance revealed adaptive variation underpinning survival in distinct habitats: L1 had the highest light absorption efficiency and lowest thermal tolerance, suggesting that it is a classic reef specialist. L3 had the lowest light absorption efficiency and the highest thermal tolerance, showing that it is an extreme reef specialist. L2 had intermediate light absorption efficiency and thermal tolerance, suggesting that is a generalist lineage. These findings reveal diverging holobiont strategies to cope with extreme conditions. Resolving coral lineages is key to understanding variation in thermal tolerance among coral populations, can strengthen our understanding of coral evolution and symbiosis, and support global conservation and restoration efforts.

Tandem dye-sensitized solar cells achieve 12.89% efficiency using novel organic sensitizers

This study presents a significant advancement in tandem dye-sensitized solar cells (T-DSSCs) through the strategic synthesis of novel triazatruxene (TAT) sensitizers MS-1 and MS-2. These organic sensitizers demonstrate exceptional light-harvesting capacity and overall performance, pushing the boundaries of power conversion efficiency (PCE) in DSSCs. The MS-1-based DSSCs achieved an impressive PCE of 12.81%, while MS-2 sensitizers reached a notable 10.92%. These efficiencies represent significant improvements over the conventional N719 dye (7.60%), demonstrating the potential of metal-free organic sensitizers in DSSC technology. The key to these noteworthy results lies in the molecular design of the organic sensitizers. The triazatruxene donor segment in the MS-1 and MS-2 dyes, featuring a rigid structure and efficient intramolecular charge transfer (ICT), proved to be a game-changer for photovoltaic properties. Building on these results, we explored an innovative parallel tandem cell (PT-DSSC) configuration. By connecting separate cells containing N719 and MS-1 sensitizers, we achieved a record efficiency of 12.89% with enhanced short-circuit current density (JSC) and open-circuit voltage (VOC)compared to single-dye cells. This study highlights the potential of molecular engineering in organic sensitizers and device optimization to enhance DSSC performance, paving the way for further advancements in solar cell technology.

Comparative Analysis of Pretreatment Methods for Fruit Waste Valorization in Euglena gracilis Cultivation: Impacts on Biomass, β-1,3-Glucan Production, and Photosynthetic Efficiency.

This study explored the sustainable valorization of fruit waste extracts from sugarcane bagasse (SB), banana peel (BP), and watermelon rind (WR) for Euglena gracilis biomass and β-1,3-glucan production. The extracts were prepared using water extraction (WE), high-temperature and pressure treatment (HTP), and dilute sulfuric acid treatment (DSA). The DSA-treated extracts consistently yielded the best results. E. gracilis cultured in SB-DSA showed the highest cell density with a 2.08-fold increase compared to the commercial HUT medium, followed by BP-DSA (1.35-fold) and WR-DSA (1.70-fold). Photosynthetic pigment production increased significantly, with chlorophyll a yield being highest in SB-DSA (1.90-fold increase). The chlorophyll a/b ratio and total carotenoid content also improved, indicating enhanced light-harvesting capacity and photoprotection. Photosynthetic efficiency, measured by chlorophyll fluorescence, notably improved. The maximum quantum yield of PSII (Fv/Fm) increased by up to 25.88% in SB-DSA, suggesting reduced stress and improved overall photosynthetic health. The potential photochemical efficiency (Fv/F0) showed even greater improvements: up to 40.53% in SB-DSA. Cell morphology analysis revealed larger cell aspect ratios, implying a more active cellular physiological state. β-1,3-glucan yield also increased by 23.99%, 12.92%, and 23.38% in SB-DSA, BP-DSA, and WR-DSA, respectively. This study demonstrates the potential of pretreated fruit waste as a cost-effective and sustainable medium for E. gracilis cultivation, offering the dual benefits of waste valorization and high-value compound production. These findings contribute to the development of more efficient biorefinery processes and align with the circular economy principles in food biotechnology.

Enhanced selective photocatalytic reduction and oxidation of perfluorooctanoic acid on Bi/Bi5O7I decorated with poly (triazine imide)

Perfluorooctanoic acid (PFOA) is detected widely in surface and groundwater globally. Its removal poses a significant challenge due to its high chemical stability. This study demonstrates efficient PFOA degradation using poly-triazine-imides-tailored defective Bi5O7I (PTI/BB). Under 300 W Xe irradiation, 1 µg·L−1 PFOA could be degraded to 9.86 ng·L−1 after 3 h in the presence of 0.5 g·L−1 25 % PTI/BB. The mechanism investigation reveals that the oxygen vacancy (OV) in partially reduced Bi/Bi5O7I (BB) generates impurity states, enhancing the light-harvesting capacity. Furthermore, forming a type Ⅱ heterojunction between conjugated PTI and BB facilitates the efficient separation of photogenerated carriers. The resulting photogenerated electrons (reduction) and holes (oxidation) drive hydrogenation reduction and oxidative decarboxylation of PFOA, respectively. This synergistic effect consequently achieves significant defluorination of PFOA. The proposed PFOA degradation pathway via the PTI/BB catalyst offers new insights into the catalyst design for photocatalytic degradation of per- and polyfluoroalkyl substances (PFAS).

Eradicating the Photogenerated Holes in a Photocatalyst-Microbe Hybrid System: A Review.

Finding advanced technologies to store solar energy in chemical bonds efficiently is of great significance for the sustainable development of our society. The recently reported photocatalyst-microbe hybrid (PMH) system couples photocatalysts intimately with microbes and endows heterotrophic microbes with light-harvesting capacity. Generally, when PMH systems are exposed to light, photocatalytic reactions occur on the surface of photocatalysts and the photogenerated electrons enter microbial cells to promote the generation of energy carriers (such as nicotinamide adenine dinucleotide phosphate hydrogen and adenosine triphosphate) and the following chemical synthesis. PMH system applications have expanded from synthesizing value-added products (chemicals, fuels, and polymers) to treating pollutants. However, the successful operation of the PMH system relies on the timely eradication of the photogenerated holes as they recombine with the photogenerated electrons and cause the photocorrosion of the photocatalyst. This review summarizes the strategies for scavenging the photogenerated holes in PMH systems and provides insight into the current gaps and outlooks for future opportunities in this field.

Z-scheme heterostructure of ZnO@NPC/Au/ZnIn2S4 for chemical replacement reaction-mediated signal-on photoelectrochemical assay of mercury ion

Herein, an advanced Zn-based metal organic framework (Zn-MOF) derived ZnO embedded in a nitrogen-doped porous carbon (ZnO@NPC) polyhedron/Au/ three-dimensional (3D) chrysanthemum-like ZnIn2S Z-scheme heterojunction was employed for the chemical replacement reaction-mediated signal-on photoelectrochemical (PEC) sensing detection of mercury ions (Hg2+). The p-type ZnO@NPC polyhedron was initially prepared by carbonising the zeolitic imidazolate framework (ZIF)-8 polyhedron, followed by modification with Au nanoparticles (NPs) via an in situ photocatalytic reduction method. Subsequently, the ZnO@NPC/Au polyhedron was combined with n-type 3D chrysanthemum-like ZnIn2S4 through physical adsorption, forming the ZnO@NPC polyhedron/Au/3D chrysanthemum-like ZnIn2S4 Z-scheme heterostructure. The newly constructed heterostructure exhibited strong visible light–harvesting capacity, and considerably improved photoelectric conversion efficiency. The 3D chrysanthemum-like ZnIn2S4 functioned not only as a photosensitiser but also as an Hg2+ recognition probe. Importantly, the PEC sensor exhibited a considerably increased photocurrent response to Hg2+. This is presumably because the introduction of Hg2+ triggered a selective Zn-to-Hg chemical replacement reaction, leading to the in-situ formation of a ZnO@NPC/Au/ZnIn2S4/HgS heterojunction, which further improved charge separation. Consequently, Hg2+ was sensitively detected with a wide linear range from 0.5 pM to 2 μM and a low detection limit of 0.07 pM. Furthermore, the proposed sensor was validated by detecting Hg2+ in food and aqueous environments, indicating its potential application in food safety and environmental monitoring.

NiO@GaN nanorods-based core-shell heterostructure for enhanced photoelectrochemical water splitting via efficient charge separation

Remarkable properties of III-V semiconductors, particularly GaN nanostructured based photoelectrodes offers a potential attention in the field of photoelectrochemical water splitting (PEC-WS) for clean and sustainable hydrogen production, due to its wide bandgap, magnificent optoelectrical properties. However, the presence of inevitable surface states in GaN nanorods (NRs) leads to low solar-to-hydrogen (STH) conversion efficiency with poor stability, thereby severely limiting their practical application in PEC-WS, which can be effectively alleviated by constructing a hybrid heterostructures. Herein, we present the development of interfacial engineering of a type-II core-shell heterostructure based on p-NiO nanoparticles (NPs) loaded on n-GaN NRs photoelectrodes for PEC-WS. We assessed the impact of the NiO NPs shell density on core GaN NRs, finding that the optimized NiO@GaN NRs photoelectrode achieved a photocurrent density (Jph) of 1.38 mA/cm² at 1.23 V versus RHE and an excellent applied bias photo-to-current conversion efficiency (ABPE) of ∼0.39 %, which was 3.8 (Jph) and 4.8 (ABPE)-fold times higher than the pristine GaN NRs photoanode under 1-Sun illumination. The type-II p-n heterojunction band alignment between core-shell NiO@GaN NRs photoelectrode effectively reduced the photogenerated carrier recombination rate through surface states passivation and boost the light absorption and harvesting capacity. This facilitates a significant charge separation and transfer at the photoanode/electrolyte interface leading to enhanced redox reactions, resulting in improved PEC-WS and STH performances. These findings offer a promising strategy to design and fabricate highly efficient III-V hybrid heterostructure photoelectrodes for futuristic PEC-WS-based green energy applications.

Spatially Separate Center-to-Surround Radiation Structure Induced Tandem Electron Transfer Effect for Stable and Enhanced Photocatalysis.

Spatially separate anchoring redox cocatalysts on the photocatalyst to shunt the charge migration paths is an effective route to regulate the charge flow. Differently, we herein introduce an artificially synthesized Sun-planet-like spatially separated center-to-surround radiation photosensitizer-cocatalyst structure to regulate electron flow in a tandem manner. A single Au sphere acts as the Sun/photosensitizer in the center, and small Pt particles scatter around as the planets/cocatalyst, both of which are fixed inside the MOF crystal. Such a structure can not only simultaneously increase the light harvesting capacity and electron migration kinetics but also optimize the electron transfer pathway to minimize the electron migration distance, so that the hot electrons generated by Au can be quickly transferred to Pt through MOF before annihilation, leading to a significant photoactivity promotion.

Multimodal integrated and broadband light-driven antibacterial cellulose fabric based on π-π coupling enhanced intermolecular FRET

Fabrication of antimicrobial photodynamic therapy (aPDT) materials based on organic photosensitizers has garnered considerable attention within functional textiles. However, the UV- or narrow-band absorption range of the photosensitizers results in poor photon utilization of the fabrics, limiting the photodynamic efficiency and wasting solar energy. In this study, a broadband light-driven antibacterial cellulose fabric (CF-ZnPc/NAD) was developed by loading carboxyl-modified zinc(II) phthalocyanine photosensitizer (CAZnPc) and cationic 1,8-naphthalimide fluorescent molecule (NAD) on the fabric via covalent binding and electrostatic adsorption assembly, facilitating the intermolecular π-π coupling and fluorescence resonance energy transfer (FRET) process. There is a 2.54-fold increase in photo-induced ROS generation capacity of CF-ZnPc/NAD via the FRET process compared to that of CF-ZnPc, and it also exhibited a strong photothermal effect (PTT), wherein the temperature of the fabric increased from 24.5 to 53.5 °C within 80 s of illumination (λ > 400 nm, 75 mW/cm2). CF-ZnPc/NAD exhibited strong light-harvesting capacity and a combination of aPDT and PTT, achieving excellent antibacterial performance against Staphylococcus aureus (Gram-positive, S. aureus) and Escherichia coli (Gram-negative, E.coli) with 99.99 % bacterial reduction under 90 min of illumination (λ > 400 nm, 10 ± 1 mW/cm2). This study demonstrates a novel and facile strategy for successfully fabricating high-performance antibacterial cellulose fabrics with potential biomedical prospects.

Copper benzene-1,3,5-tricarboxylate based metal organic framework (MOF) derived CuO/TiO2 nanofibers and their use as visible light active photocatalyst for the hydrogen production

Photocatalytic hydrogen generation through water splitting offers a sustainable and renewable approach to producing green and clean hydrogen fuel. However, it is crucial to explore low-cost semiconductor photocatalysts that can effectively capture a broad range of solar radiation. The present study aims to develop photocatalytic CuO/TiO2 nanofibers (NFs) with homogeneity of copper with titanium in the heterostructures through the metal–organic framework (MOF) assisted strategy via the electrospinning and subsequent calcination approach. The new methodology enables the fabrication of CuO-modified TiO2 NFs based on HKUST-1 (copper benzene-1,3,5-tricarboxylate, Hong Kong University of Science and Technology-1) as Cu-MOF varying the amounts of HKUST-1. Ultraviolet–visible light diffuses reflectance spectroscopy (DRS), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), photoluminescence spectroscopy (PL), X-ray photoemission spectroscopy (XPS) and Raman spectroscopy are employed to assess the structural and morphological characteristics of the prepared NFs. The characterization revealed that the CuO-TiO2 NFs heterostructure was uniform. The bandgaps of the CuO-TiO2 NFs ranged from 3.08 to 2.83 eV based on the Kubelka–Munk function, which is considerable for improving the light-harvesting capacity. The photocurrent technique is used to confirm efficiency in charge separation and transfer, as well as a longer lifetime of photo-generated charge carriers effect in photocatalytic activity. In addition, density functional theory calculations were performed to analyze the impact of CuO on the geometric, electronic structure and photocatalytic properties of TiO2. The CuO/TiO2 photocatalyst containing 1.5 mol% of CuO exhibited the highest photocatalytic activity. The hydrogen production rate was exceptional at 45.6 mmol·g−1·h−1, which was a remarkable 400 times higher than that achieved with pure TiO2 nanofibers. Owing to the one-dimensionality of nanostructures, the prepared CuO-based TiO2 NFs had high recyclability without lessening the efficiencies of photocatalytic activity.

Ozone Priming Enhanced Low Temperature Tolerance of Wheat (Triticum Aestivum L.) based on Physiological, Biochemical and Transcriptional Analyses.

Low temperature significantly inhibits plant growth in wheat (Triticum aestivum L.), prompting the exploration of effective strategies to mitigate low temperature stress. Several priming methods enhance low temperature stress tolerance; however, the role of ozone priming remains unclear in wheat. Here we found ozone priming alleviated low temperature stress in wheat. Transcriptome analysis showed that ozone priming positively modulated the 'photosynthesis-antenna proteins' pathway in wheat under low temperature. This was confirmed by the results of ozone-primed plants, which had higher trapped energy flux and electron transport flux per reaction, and less damage to chloroplasts than non-primed plants under low temperature. Ozone priming also mitigated the overstimulation of glutathione metabolism and induced the accumulation of total ascorbic acid and glutathione, as well as maintaining redox homeostasis in wheat under low temperature. Moreover, gene expressions and enzyme activities in glycolysis pathways were upregulated in ozone priming compared with non-priming after the low temperature stress. Furthermore, exogenous antibiotics significantly increased low temperature tolerance, which further proved that the inhibition of ribosome biogenesis by ozone priming was involved in low temperature tolerance in wheat. In conclusion, ozone priming enhanced wheat's low temperature tolerance through promoting light-harvesting capacity, redox homeostasis and carbohydrate metabolism, as well as inhibiting ribosome biogenesis.

Application of multilevel immobilized carbon nanotube/sulfur doped carbon nitride composite photocatalytic coating for Cr6+(aq.) reduction

The difficulty in immobilizing carbon nitride (GCN), and the decrease in sorption capacity and photocatalytic performance after immobilization process have become two major bottlenecks limiting the practical application of carbon nitride in photocatalysis field. Herein, sulfur doped carbon nitride and carbon nanotube composite photocatalysts (CNT/SCN) with high sorption, light harvesting capacity, and reduction efficiency was synthesized by two-step solvothermal method. Furthermore, CNT/SCN composite photocatalytic coating with porous three-dimensional surface morphology was prepared using double liquid phase high speeding spray-deposition method. The coverage rate of CNT/SCN coating was calculated to be 55 %, which was 1.57 times higher than that of GCN coating. The introduction of carbon nanotube (CNT) significantly improved the sorption capacity of photocatalytic coating for hexavalent chromium (Cr6+(aq.)). The reduction efficiency of the composite coating towards Cr6+(aq.) under flowing water conditions was further investigated. The CNT/SCN coating exhibited a high removal efficiency of 84.7 % for Cr6+(aq.) (500 mL, 10 mgL−1) within 8 h, which was 29 times than that of GCN coating. The reduction efficiency of CNT/SCN photocatalytic coating remained above 75 % after three cycles of testing. This research provides theoretical basis and data support for the immobilization application of photocatalysts.

A novel Z-scheme SnS/NiAl-LDH/g-C3N4 heterojunction for piezo-photocatalytic degradation of tetracycline: Performance and mechanism

The construction of a heterojunction piezo-photocatalyst is one of the most effective strategies to accelerate charge transfer and improve catalytic performance. A novel ternary heterojunction was synthesized by introducing SnS nanoparticles (NPs) onto the surface of a NiAl-LDH/g-C3N4 (LDH/CN) nanosheets via a facile hydrothermal method. The separation and transfer paths of carriers was studied for the piezo-photocatalytic degradation of tetracycline (TC), a common antibiotic, under ultrasonic and visible light irradiation. The SnS/LDH/CN piezo-photocatalyst generated a built-in electric field by the piezoelectric effect, which was beneficial for the separation of electron-hole pairs. Furthermore, the Z-scheme heterojunction endowed with a larger surface area, abundant active sites, and improved light-harvesting capacity further improved piezo-photocatalytic performance for TC. In particular, a CLS-30 (30 wt% of SnS on LDH/CN) heterojunction exhibited the highest degradation efficiency with 98.5 % removal of TC (20 mg/L) in 60 min, which was higher than that of ultrasonic vibration (38.2 %) and visible light illumination (79.4 %). TC degradation efficiency remained at almost 90 % after 4 consecutive cycles. This work provides a novel viewpoint for designing high-performance and stable heterojunction piezo-photocatalysts for energy limited wastewater remediation applications.

High-efficiency ultra-thin GaAs solar cells based on ITO/Ag/ITO transparent electrodes and photonic crystals

Ultrathin photovoltaic technology has great potential to improve efficiency and reduce costs. However, achieving optical thickness requires an effective light capture strategy. In this study, for GaAs thin film solar cells with an active layer thickness of 500 nm, we adopt a combination strategy of front-end ITO/Ag/ITO transparent electrodes and back-end photonic crystals (PC). By employing the finite difference time domain (FDTD) simulation, we verify that ITO/Ag/ITO transparent electrodes and AlGaAs PC can effectively enhance the light-harvesting capacity of cells. The proposed cell structure has a spectral absorption rate (SAR) of 0.9781 in the visible wavelength range. To further optimize the photovoltaic performance parameters, we optimize the doping concentration of the pn junction in the cell. Finally, the short circuit current density Jsc, open circuit voltage Voc, fill factor (FF) and photoelectric conversion efficiency (PCE) of GaAs thin film solar cells are successfully increased to 31.10mAcm−2, 1.28V, 88.18% and 35.12%, respectively. This provides crucial experimental validation and theoretical guidance for advancing ultra-thin photovoltaic technology.

In situ fabrication of 2D Ti3C2/1T&2H-MoS2/TiO2 photocatalyst for sulfamethazine degradation

Sunlight-driven photocatalysis is a very appealing approach for solving the current energy crisis because it will not cause secondary pollution. Titanium dioxide (TiO2) has attracted much attention in the field of photocatalysis due to its simple preparation, environmental friendliness and easy modification. However, reducing the band gap and expanding the light absorption range to reduce the carrier recombination rate of TiO2 is still a huge challenge. Herein, we report a two-dimensional (2D) Ti3C2/1 T&2 H-MoS2/TiO2 photocatalyst obtained by in situ growth of a 1 T&2 H-MoS2/TiO2 Z-scheme heterojunction on a highly conductive Ti3C2 MXene surface. The spectral response range of the resulting Ti3C2/1 T&2 H-MoS2/TiO2 (Ti3C2:1 T&2 H-MoS2:TiO2= 1:10:10) photocatalyst was broadened to 696 nm and the band gap was reduced to 1.83 eV, which was responsible for the strong light-harvesting capacity and improved charge separation. The activity of the Ti3C2/1 T&2 H-MoS2/TiO2 photocatalyst was evaluated by photocatalytic degradation of sulfamethazine (SMZ). The degradation rate of SMZ reached 99.8 % after 90 min of illumination. These results demonstrate that the combination of Ti3C2 MXene and heterojunction is a feasible strategy to enhance the light-harvesting capacity and charge transport in photocatalytic reaction.

Modification of CdZnS nanoparticles on nanoporous FeVO4 photoanode to improve photoelectrochemical performance

Photoelectrochemical (PEC) performance of semiconductor photoanode can be significantly improved by regulating the energy band alignment to promote carrier separation. This study demonstrates the first application of CdZnS (CZS) nanoparticles to modify FeVO4 (FVO) nanostructure phoyoanode for PEC water splitting. The constructed FVO/CZS photoanode exhibits significantly enhanced PEC performance with a zero-bias solar-driven photocurrent density of 1.00 mA/cm2, which is 11 times and 4.5 times that of unmodified FVO and CZS, respectively. The Tests of the optical absorption and electrochemical spectroscopy demonstrate that the modification of CZS nanoparticles not only improves the light harvesting ability of the FVO/CZS heterojunction nanostructures in the wavelength of 300–500 nm but also establishes a type II band alignment between the interface of FVO and CZS that is conducive to the transport and separation of the charge carriers and prolongs charge lifetime. Consequently, synergistic actions of the improved light harvesting capacity, effective charge transport and separation and the prolonged carrier lifespan enable the designed and fabricated FVO/CZS heterojunction photoanode to get substantially augmented PEC water splitting performance. This work supplies an innovative guidance for designing FVO-based photoanodes to improve photoelectric conversion behavior from the perspective of interface engineering.