Search Results (2,407)

Organic pollutants in industrial wastewater present a severe threat to both the environment and human health. Photocatalytic technology, recognized for its eco-friendliness and high efficiency, has become a leading approach for degrading such pollutants. In this work, BiOCl nanosheets were first synthesized using a hydrothermal method. Subsequently, an anion exchange reaction with TAA in an oil bath generated a Bi₂S₃ intermediate layer on the BiOCl surface, followed by the in situ growth of ZIS nanostructures, successfully constructing a BiOCl@Bi₂S₃@ZIS double Z-scheme heterojunction. By adjusting the amount of BiOCl, the interface contact and dispersion of the heterojunction were optimized. Characterization results demonstrate that the BiOCl@ZIS-25 heterojunction possesses the highest specific surface area (103.5 m²·g⁻¹) and the most efficient charge separation. Under visible light irradiation, it achieved 97.88% degradation of methylene blue within 20 min, with a reaction rate constant 8 and 4 times higher than those of pure BiOCl and ZIS, respectively. Mechanistic investigations indicate that Bi₂S₃ interlayer acts as an electron-transfer bridge between BiOCl and ZIS, establishing a double Z-scheme charge transfer pathway that significantly enhanced the separation and utilization efficiency of photogenerated charge carriers. This study offers valuable insights for designing highly efficient and stable photocatalytic composite materials. Full article

The design of solar cells with a bulk heterojunction is one of the most promising areas in renewable energy sources. Acceptor dopants with suitable physical characteristics are desirable components for ternary organic solar cells with cascade charge transfer. In this Short Note, 2-(4H-indeno[2,1-d][1,2,3]thiadiazol-4-ylidene)-1H-indene-1,3(2H)-dione was prepared by thionation of [1,2′-biindenylidene]-1′,3,3′(2H)-trione with Lawesson’s reagent in refluxing benzene. The structure of newly synthesized compound was strictly confirmed by spectral methods. The obtained optical and electrochemical properties make this compound a promising candidate for use in ternary organic solar cells. Full article

The electrocatalytic reduction of CO₂ into value-added chemicals offers a promising route to mitigate greenhouse gas emissions, yet the uncontrollable structural reconstruction and surface rearrangement of electrocatalysts during operation often lead to severe activity degradation. Herein, we reveal that Bi₂O₂SO₄ (BSO) undergoes an irreversible phase transformation into Bi₂O₂CO₃ (BCO) nanosheets accompanied by the partial reduction of Bi³⁺ to metallic Bi⁰ under cathodic potentials. A series of BCO/BSO heterojunction catalysts with tunable compositions are synthesized via a mild in situ ion-exchange method. To circumvent the detrimental effects of this dynamic reconstruction, we devise a pre-activation strategy that deliberately completes the structural evolution prior to electrocatalysis. The optimized 20%-BCO/BSO heterojunction achieves a remarkable Faradaic efficiency of 98.4% for formate production in a flow cell at elevated potentials, with >95% FE_(HCOOH) over a wide potential window (−0.8 to −1.7 V vs. RHE). In situ infrared spectroscopy elucidates that the reconstructed interface can promote CO₂ adsorption, stabilize the *OCHO intermediate, and facilitate HCOOH desorption. This work provides experimental evidence of the reconstruction behaviour of bismuth-based catalysts and offers a rational design method for constructing structurally stable heterojunction electrocatalysts. Full article

SrTiO₃/Nb₂O₅ composite materials with 1 and 10 wt.% Nb₂O₅ were prepared by a sol–gel route and characterized by XRD, Raman spectroscopy, SEM, BET, UV-Vis DRS, photoluminescence, and dielectric spectroscopy. The photocatalytic activity was evaluated via degradation of rhodamine B and tetracycline under UV and visible light. The addition of Nb₂O₅ resulted in a significant reduction in specific surface area (from 22.7 to 3.1 m²/g), a narrowing of the optical band gap (from 3.22 to 2.49 eV), and a decrease in photoluminescence intensity. Despite these changes, the photocatalytic performance decreased with increasing Nb₂O₅ content. For rhodamine B degradation, the UV rate constant fell from 0.0136 min⁻¹ for pristine SrTiO₃ to 0.0035 min⁻¹ for SrTiO₃/10% Nb₂O₅. The lower activity is mainly ascribed to the loss of active sites, surface carbonate formation, and enhanced non-radiative recombination at interface defects, which suppress charge transfer to the surface. The results demonstrate that careful control of the composite microstructure is essential for achieving efficient photocatalysis, even when heterojunction formation is thermodynamically favorable. Full article

Photocatalytic antibacterial coatings have emerged as a promising antibiotic-free strategy for combating healthcare-associated infections, biofilm formation, marine biofouling, and environmental microbial contamination. Unlike conventional antimicrobial approaches, photocatalytic systems continuously generate reactive oxygen species (ROS) under light irradiation, enabling broad-spectrum antimicrobial activity while minimizing the risk of antimicrobial resistance. This review systematically summarizes the fundamental mechanisms underlying photocatalytic antibacterial activity, including photogenerated charge-carrier dynamics, ROS generation pathways, and microbial inactivation processes. We further highlight recent advances in photocatalyst design, spanning conventional semiconductor photocatalysts, heterojunction engineering, cocatalyst modification, and two-dimensional material-assisted strategies for enhanced photocatalytic performance. Crucially, particular emphasis is placed on coating architectures and interfacial regulation, including encompassing fabrication methodologies, coating–substrate adhesion, internal heterointerface design, and coating–microorganism interactions, which dictate long-term durability and antibacterial efficacy. Finally, we explore the diverse applications of these coatings in medical devices, environmental remediation, and marine antifouling, while identifying current bottlenecks and future research trajectories toward developing durable, highly efficient, and clinically translatable antimicrobial surface technologies. Full article

Implantable neural probes that can simultaneously possess biocompatibility, electrochemical stability, and high signal fidelity are the core devices in neuroelectrophysiological research. In this article, AlGaN/GaN heterojunction field-effect transistors are used instead of traditional metal microelectrodes to prepare brain nerve probes. By photoelectrochemical etching and optimization of sensing area size, the probes have the maximum transconductance value, i.e., the highest sensitivity, under no gate control. After digital filtering processing, the neural probe achieved a signal-to-noise ratio of 8.04 dB on biological analog signals as low as 50 µV, confirming its ability to detect microvolt-level signals. The ex vivo recording of the bullfrog sciatic nerve further validated its biosensing performance, demonstrating the selective capture of composite action potentials from active neural tissue. Full article

Photocatalytic fuel cells (PFCs) integrate photocatalysis with fuel cell technology to enable simultaneous wastewater treatment and energy recovery. This review examines recent advances in PFC cathode materials, focusing on design strategies, reduction mechanisms, and applications. The cathode governs electron transfer and interfacial reactions, including oxygen reduction (4e⁻ or 2e⁻ pathways), direct pollutant electroreduction, and oxidant activation for radical generation. Cathodic materials including transition metal oxides/sulfides, carbon-based materials, metal–organic frameworks and their derivatives, are systematically summarized, evaluating their respective activities, stabilities and costs. Rational design via heterojunction engineering, defect modulation, and composite construction enables tunable reaction pathways and enhanced performance. Furthermore, representative applications are reviewed, with particular attention to the effective degradation of organic pollutants, and reduction of heavy metals and radionuclides in PFCs. Future efforts should prioritize long-term stability, scalable fabrication, and multi-functional cathode integration. Full article

Effective terahertz (THz) modulation remains a critical challenge for advancing THz technology. Recently, two-dimensional (2D) materials integrated with high-resistance silicon (Si) have emerged as promising heterojunction platforms for THz control. In this paper, we experimentally demonstrate an all-optically controlled THz modulator based on a large-area WSe₂/Si heterojunction, fabricated by magnetron sputtering of tungsten on Si followed by vacuum selenization. The device exhibits broadband modulation across 0.1–1.1 THz, achieving a modulation depth of 72% at a pump power of 1500 mW/cm², significantly higher than that of bare Si or pristine WSe₂ films. Moreover, we systematically analyze the underlying mechanism responsible for this enhanced performance. This study presents an effective and scalable strategy for THz modulation using 2D material/Si heterojunctions. Full article

Developing efficient photoelectrocatalysts is crucial for advancing sustainable energy solutions to generate green hydrogen, particularly in photoelectrochemical water splitting. This study addresses these limitations by synthesizing and characterizing WO₃/(W)BiVO₄ heterojunctions incorporated with graphitic carbon nitride (C₃N₄). Our approach combines a microwave-assisted synthesis for heterojunction formation with the direct polymerization of C₃N₄, aiming to enhance the charge separation and light absorption. Structural and morphological analyses confirmed the presence of well-defined heterojunctions with homogeneous element distributions, while spectroscopic studies demonstrated enhanced visible light absorption. Our results show the potential of WO₃/(W)BiVO₄/C₃N₄ systems as durable and efficient photoanodes. The further optimization of polymerization conditions and band alignment strategies may unlock greater efficiency, paving the way for more effective solar-driven hydrogen production. Full article

Room-temperature sodium–sulfur batteries have broad prospects, but Na₂S cathodes suffer from poor electrochemical performance and insufficient air stability. By introducing Na₂SeO₃ as a precursor, a Na₂Se/Na₂S@CNF composite cathode is prepared. TEM reveals continuous heterojunction interfaces. Electrochemical performance is significantly enhanced: the initial charge capacity reaches 664 mAh g⁻¹, and the reversible capacities at 0.2, 0.5, 1, 2, 3, and 5 C rates are 774, 722, 636, 574, 494, and 396 mAh g⁻¹ respectively, with a reversible capacity of 600 mAh g⁻¹ after 300 cycles at 1 C. Full article

The global demand for hydrogen peroxide (H₂O₂) continues to increase, and photocatalytic H₂O₂ production is regarded as a promising alternative technology due to its mild, safe, and environmentally friendly characteristics. ZnIn₂S₄ has demonstrated promising application potential in photocatalytic H₂O₂ production owing to its unique two-dimensional layered structure and broad spectral response. However, its performance is severely limited by rapid charge recombination and sluggish charge migration. To address this challenge, a ZnIn₂S₄/C₃N₄ S-scheme heterojunction was successfully constructed via a simple oil-bath method by assembling ZnIn₂S₄ nanoflowers on C₃N₄ nanosheets. Systematic structural characterizations and performance evaluations demonstrate that the construction of the S-scheme heterojunction effectively promotes the spatial separation and surface migration of photogenerated charge carriers, thereby significantly enhancing photocatalytic activity. Under optimal conditions, the ZIS/CN-10 sample (C₃N₄ to ZnIn₂S₄ mass ratio of 10%) achieves the highest photocatalytic H₂O₂ production rate of 825.8 μmol g⁻¹ h⁻¹. This work provides new insights and theoretical guidance for the rational design of efficient and stable ZnIn₂S₄-based photocatalysts. Full article

Metal/semiconductor heterojunctions for hot carrier photodetection have garnered significant attention. However, enhancing the quantum efficiency remains a critical challenge. Introducing lattice strain into metallic materials offers a viable approach to enhance the performance of TiN/TiO₂ hot electron photodetectors by effectively modulating their electronic structure. Herein, we investigate how strain influences the electronic structure of TiN and consequently affects the generation, transport, and injection processes of hot carriers using first-principles calculations. Subsequently, we evaluate the injection efficiency and responsivity of the TiN/TiO₂ photodetector through Monte Carlo simulations. We find that compressive strain renders the energy bands more delocalized and reduces the density of states DOS, leading to diminished hot electron generation, especially in the high-energy region above the Schottky barrier. This reduction suppresses electron–electron scattering, thereby increasing the hot electron lifetime and mean free path. Consequently, the hot electron injection efficiency is enhanced, ultimately improving the responsivity of TiN/TiO₂ photodetector by a factor of 1.3–2.4 over the incident photon energy range of 0.1–3 eV. Full article

As the most critical component of organic solar cells (OSCs), the morphology of the active layer directly dictates the photovoltaic performance of the devices. Recent studies have demonstrated that tailoring the active layer morphology using solid additives is a facile and effective strategy to boost the performance of OSCs. Herein, we design and synthesize a novel solid additive, 5-bromobenzo[b]thiophene (5-BrBT), by introducing a bromine substituent onto the common benzothiophene unit. It is found that 5-BrBT optimizes the active layer formation process by effectively prolonging the nucleation time, which facilitates more controllable molecular nucleation and subsequent crystal growth during the pre-aggregation stage, leading to a more ideal donor-acceptor phase distribution. Furthermore, the binary PM6:L8-BO organic solar cells, fabricated with the incorporation of 5-BrBT, exhibit superior charge transport properties and exciton-generation efficiency, along with significantly suppressed charge recombination behaviors. Consequently, the 5-BrBT-treated binary PM6:L8-BO-based OSCs achieve an outstanding power conversion efficiency (PCE) of up to 19.44%, accompanied by simultaneous enhancements in short-circuit current density (J_SC) and fill factor (FF). This work provides a promising optimization strategy for achieving ideal nucleation behaviors during the bulk-heterojunction (BHJ) film processing via solid additives, which is expected to promote the development of more efficient OSCs. Full article

The research on semiconductor electrocatalysts has developed into an active field of study in the past decade. By constructing heterojunctions, one may efficiently overcome the limitations of semiconductors’ broad band gaps and low conductivity. This work uses a single-step hydrothermal approach to load nitrogen-doped carbon quantum dots onto TiO₂ nanoparticles, resulting in an excellent N−CQDs/TiO₂ catalyst with an Ohmic contact effect for better NORR electrocatalytic performance under ambient circumstances. The ammonia production rate is 4242.24 μg·h⁻¹·mg⁻¹ at an applied potential of −0.90 V vs. RHE (in a 0.10 M K₂SO₄ electrolyte), and the Faradaic efficiency is 88.02%. When compared to the unmodified TiO₂ catalytic performance, the ammonia generation rate doubles, and the Faradaic efficiency increases by 42.90%. A detailed investigation of the microstructure, charge transfer, NO adsorption, and reaction pathways of N−CQDs/TiO₂ was performed using density functional theory (DFT) computations. According to the theoretical results, nitrogen doping creates an uneven charge distribution on carbon quantum dots, enhancing NO adsorption by N−CQDs. The Ohmic contact between N−CQDs and TiO₂ facilitates charge transfer. The ICOHP value is more negative during NO adsorption on N-doped carbon quantum dots, decreasing the N=O interaction and boosting the NORR, according to crystal orbital Hamilton population (COHP) research. We have established the excellent performance and catalytic mechanism of the N−CQDs/TiO₂ catalyst based on these discoveries, giving strong theoretical and experimental evidence for the creation of effective catalysts for nitrogen oxide reduction processes. Full article

A series of donor–acceptor π-conjugated polymers based on Difluorophenazine acceptor and benzodithiophene donor units with different substituents, hydrogen (H), chlorine (Cl), fluorine (F), and sulfur (S), was designed and synthesized to investigate how donor-side substituent modification influences optoelectronic properties. The substituent variation systematically modulated the optical band gaps (1.72–1.82 eV) and HOMO energy levels (−5.42 to −5.58 eV). When applied in bulk heterojunction solar cells with the Y6 acceptor, these polymers delivered power conversion efficiencies ranging from 3.85% to 7.79%. The fluorinated polymer P(BDTTF-TffPzT) exhibited the best performance, with J_sc = 19.65 mA cm⁻², V_oc = 0.825 V, and FF = 0.481. These findings establish that donor-side substituent engineering is an effective molecular design strategy for tuning optoelectronic properties and device performance in phenazine-based polymer systems. Full article