- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
ZnO/CdS/PbS nanotube arrays with multi-heterojunctions for efficient visible-light-driven photoelectrochemical hydrogen evolution
摘要： High performance, low cost and sustainable photocatalytic evolution of hydrogen is a promising energy supply alternative for modern society to resolve the depletion crisis of fossil fuel. The design of multi-heterojunction visible-light photocatalysts combined with electrochemical means is considered one of the most attractive options in recent years. In this work, a photoanode composed of top-opened ZnO/CdS/PbS nanotube arrays (ZnO/CdS/PbS ONTs) with multi-heterojunctions was synthesized via a three-step process, i.e. hydrothermal treatment, chemical bath deposition and successive ionic layer adsorption reaction (SILAR). This as-prepared photoanode exhibited remarkable photoelectrochemical activity under visible light irradiation. The photocurrent density and photoelectrochemical hydrogen evolution efficiency of the optimized ZnO/CdS/PbS ONTs reached up to 14.2 mA cm-2 and 5.5 mL cm-2 h-1 at 0.0 V vs. Ag/AgCl, respectively. The efficiency was 3.1 times that of top-closed ZnO/CdS nanotubes (1.8 mL cm-2 h-1). The experimental results suggest that the high photoelectrochemical activity can be ascribed to the inherent advantages of the structural and successive energy level relays design: on the one hand, the top-opened nanotube structure significantly enlarges surface area of the nanostructure, which facilitates efficient light absorption and rapid mass transport; on the other hand, the well-matched band energy edge of the multi-heterojunction interfaces literally build efficient electron highways to deliver electrons to reaction sites and reduce the recombination of photogenerated charge carriers.
关键词： CdS,visible light,multi-heterojunction,ZnO,photoelectrochemical hydrogen evolution,PbS
更新于2025-09-23 15:22:29
-
2D-Porphrinic Covalent Organic Framework-Based Aptasensor with Enhanced Photoelectrochemical Response for the Detection of C-Reactive Protein
摘要： In this study, a novel photoelectrochemical (PEC) aptasensor based on two-dimensional (2D) porphyrinic covalent organic frameworks (p-COFs) for the label-free detection of C-reactive protein (CRP) is presented. The obtained p-COFs possess high conductivity and an improved stability due to strong and rigid covalent linkages. The introduction of p-COFs hinder the recombination of electrons and holes, decreasing their band gap (Eg), thereby which improved the photocurrent conversion efficiency. Compared with pure porphyrin, p-COFs exhibited enhanced photocurrent intensity. An amplified photocurrent conversion efficiency and enhanced photocurrent results from H2O2, which act as active molecules and electron donors. As an unprecedented application of COFs in PEC bioanalysis, the detection of CRP with a PEC aptasensor is presented. The assembly of a CRP aptamer on the surface of Ag nanoparticles hinders the electron transfer, resulting in the decrease of the photocurrent response. This PEC aptasensor exhibits good analytical performances such as a rapid response, high stability, wide linear range and excellent selectivity, making COFs promising candidates for PEC bioanalysis.
关键词： C-reactive protein,Porphyrinic covalent organic framework,High photocurrent conversion efficiency,Photoelectrochemical aptasensor,Enhanced photocurrent
更新于2025-09-23 15:22:29
-
A promising CuOx/WO3 p-n heterojunction thin-film photocathode fabricated by magnetron reactive sputtering
摘要： A CuOx/WO3 thin-film based on p-n heterojunction proposed as a highly performance and stable photocathode. The CuOx/WO3 thin-film was deposited by magnetron reactive sputtering layer by layer, followed with slow rate annealing in O2 ambient. This is an excellent method for high-quality and uniform composite thin-film deposition with large areas at a high growth rate. The optimized CuOx/WO3 thin-film photocathode after slow rate annealing at 500 °C in O2 provides an obviously enhanced photoinduced current density of -3.8 mA cm-2 at a bias potential of -0.5 V (vs. Ag/AgCl), which value is 1.5 times higher than that of bared CuOx thin-film. This highly enhanced photoelectrochemical performance is attributed to p-n heterojunction, which accelerates the photogenerated electrons and holes transfer to n-WO3 and p-CuOx, thereby accelerate the separation of photogenerated carries. In addition, WO3 layer covered on the surface of CuOx thin film can improve the stability of Cu2O in electrolytes.
关键词： p-n heterojunction,Tungsten oxide,Photoelectrochemical,Copper oxide,Magnetron reactive sputtering
更新于2025-09-23 15:22:29
-
Layered Double Hydroxides Decorated Graphic Carbon Nitride Film as Efficient Photoanodes for Photoelectrochemical Water Splitting
摘要： In the present work, we investigate the graphic carbon nitride (g-CN) film as photoanode to catalyze the photoelectrochemical (PEC) water oxidation and study the influence of NiCo layered double hydroxides (NiCo-LDH) layer on the performance. The g-CN film with good quality and intimate contact with substrate was in-situ prepared via solvothermal process and subsequent calcination. NiCo-LDH is further decorated on the g-CN film through cathodic electrochemical deposition to work as co-catalyst. The g-CN/NiCo-LDH composite with optimized NiCo-LDH loading amount exhibits a photocurrent of 11.8 μA cm-2 at 0.6 V vs. SCE, which is 2.8 times of bare g-CN. Characterizations and performance tests demonstrate that NiCo-LDH promoted reaction kinetics and charge separation. The results provide an effective strategy to improve the photoelectrochemical water oxidation performance of g-CN through NiCo-LDH co-catalyst. This work to investigate the photoelectrochemical water oxidation is of great significance toward explore the overall water splitting on the g-CN film.
关键词： Layered double hydroxides,Solvothermal process,Photoelectrochemical water oxidation,Co-catalyst,Graphitic carbon nitride
更新于2025-09-23 15:22:29
-
Multifunctional monoclinic VO2 nanorod thin films for enhanced energy applications: Photoelectrochemical water splitting and supercapacitor
摘要： Monoclinic VO2 nanorod thin films were deposited on indium?tin-oxide-coated glass substrates using radio-frequency reactive magnetron sputtering at a substrate temperature of 300 °C and various O2 flow rates. The thin films were characterized via standard analysis techniques. The VO2 thin films exhibited a highly crystalline monoclinic phase with an indirect band gap of ~1.73 eV. At optimized O2 flow rate (4 sccm), the thin films was observed nanorod structures, exhibited a remarkable photocurrent of ~0.08 mA cm?2 during photoelectrochemical water splitting in the visible region. Electrochemical performance tests of the nanorod films revealed a specific capacitance of ~486 mF cm?2 at a scan rate of 10 mVs?1. In addition, amperometric I–t curves showed that VO2 thin film electrodes were highly stable during the photo-oxidation process. The nanorod films also exhibited a good specific capacitance of ~120 mF cm?2 after 5000 cycles at a scan rate of 100 mVs?1. The photocurrents during photoelectrochemical water splitting and the specific capacitance of VO2 thin films deposited at O2 flow rates of 2 and 6 sccm were 0.06 and 0.07 mA cm?2 and 398 and 37 mF cm?2, respectively. The films deposited under Ar at 8 sccm and O2 at 4 sccm showed the highest photoelectrochemical water splitting performance and specific capacitance, owing mainly to their nanorod-like morphology.
关键词： Supercapacitor,Partial pressure,Reactive sputtering,Photoelectrochemical water splitting,VO2,Monoclinic
更新于2025-09-23 15:22:29
-
Evidencing enhanced charge-transfer with superior Photocatalytic degradation and Photoelectrochemical water splitting in Mg modified few-layered SnS2
摘要： Recently there has been immense interest in the exploration of richly available two-dimensional non-toxic layered material such as tin disulfide (SnS2) for potential employment in energy and environmental needs. In this regard, we report on the synthesis of few-layered Sn1?xMgxS2 nanosheets through a facile one-step hydrothermal route to address all such functions concerning photocatalysis and photoelectrochemical conversion. The crystalline order and structure of processed layered Sn1?xMgxS2 were initially found to exhibit a strong influence on their physicochemical properties. Their optical properties attest the Mg doping in SnS2 to benefit us with enhanced visible-light absorption via red-shift in their absorption edge. In the photoluminescence spectrum the emissions observed along visible and red region signifies the association of Mg related trap states in Sn1?xMgxS2. Next, the photocurrent and electrochemical impedance spectroscopic results revealed the Mg doping to promote the effective charge transfer process (which was beneficial to enhance their photocatalytic activity). Consequently, the layered Sn0.98Mg0.02S2 made photoanodes displayed 1.7 fold higher photocurrent density under simulated solar radiation with respect to their undoped counterpart. Furthermore, the layered Sn0.98Mg0.02S2 nanosheets exhibits enhanced visible light decomposition of organic dye while compared with pristine SnS2 nanosheets. The value of rate constants obtained for the Sn0.98Mg0.02S2 nanosheets was found to be 1.4 times higher than that of pristine SnS2. Finally, the results obtained through the present study projects the huge potential of layered Sn0.98Mg0.02S2 nanosheets for future multifunctional applications.
关键词： SnS2,Magnesium,Nanosheets,Photocatalysis,Few-layered,Photoelectrochemical water splitting
更新于2025-09-23 15:22:29
-
Organic-inorganic hybrid perovskite – TiO2 nanorod arrays for efficient and stable photoelectrochemical hydrogen evolution from HI splitting
摘要： Solar-driven photoelectrochemical (PEC) hydrogen production offers a promising solution to simultaneously tackle the global energy crisis and the environmental pollution. Herein, we report a PEC cell of organic-inorganic hybrid perovskite (methylammonium lead iodide, MAPbI3)-TiO2 nanorod array (TNAs) for efficient and stable hydrogen evolution in aqueous hydrogen iodide (HI) solution. The built-in electric field created across the MAPbI3-TiO2 junction is able to efficiently separate the electron-hole pairs photogenerated in MAPbI3 with electrons quickly injected from MAPbI3 to TiO2, which are then transported along the one-dimensional TiO2 nanorod channels to the counter electrode to reduce proton to evolve hydrogen. The optimized MAPbI3-TNA PEC cell exhibits a high photocurrent density of 1.75 mA cm-2 at 0.14 V (vs. Ag/AgCl) under AM 1.5G illumination, which is able to stably produce molecular hydrogen at a rate of 33.3 mmol cm-2 h-1 for more than 8 h.
关键词： Perovskite,Nanorod arrays,Hydrogen evolution,Heterojunction,Photoelectrochemical
更新于2025-09-23 15:22:29
-
Multi-layered WO3 nano-platelets for efficient photoelectrochemical water splitting: the role of the annealing ramp
摘要： Multi-layered WO3 nano-square platelets films were successfully grown on transparent TCO substrates by spray-coating of WO3 nanoparticles aqueous suspension prepared by the sol-gel method. This work assesses the influence of two annealing schemes in the photo-response of WO3 photoelectrodes with different film thicknesses. The photoelectrochemical characterization reveals that the slow-heating ramp produces a photoelectrode with an improved photocurrent density of 1.6 mA·cm-2 at 1.23 V vs RHE. Comparing photoelectrodes with the same film thickness, the slow-heating ramp yield higher photocurrent densities; 80 % more than the conventional fast-heating ramp. The effect of the annealing ramp on the morphology and crystalline-phase structure of WO3 photoelectrodes is correlated with the photocurrent density. The slow-heating ramp annealing unveils film morphology with both, higher porosity degree and higher nano-square platelets dimensions. DRX structural analyses disclose that the films grow in monoclinic crystalline phase with a textural preferential direction [002], often related to improved photocurrent performances. The crystallite sizes and lattice microstrain are estimated using a simple X-ray diffraction broadening method, the Williamson-Hall analysis. A quantified correlation between the WO3 lattice defects, intergrains strain and performance is performed. The proposed deposition method paves the way for producing efficient and scalable photoelectrodes of WO3 for photoelectrochemical water splitting by using low-cost and simple manufacturing processes.
关键词： annealing ramp,X-ray peak broadening,tungsten trioxide,nano-platelets,photoelectrochemical cells,photoelectrodes
更新于2025-09-23 15:22:29
-
Nanostructuring Strategies To Increase the Photoelectrochemical Water Splitting Activity of Silicon Photocathodes
摘要： Photoelectrochemical water splitting is a promising route for sustainable hydrogen production. Herein, we demonstrate a photoelectrode motif that enables a nanostructured large-surface area electrocatalyst without requiring a nanostructured semiconductor surface with the goal of promoting electrocatalysis while minimizing surface recombination. We compare the photoelectrochemical H2 evolution activity of two silicon photocathode nanostructuring strategies: (1) direct nanostructuring of the silicon surface and (2) incorporation of nanostructured zinc oxide to increase the electrocatalyst surface area on planar silicon. We observed that silicon photocathodes that utilized nanostructured ZnO supports outperformed nanostructured silicon electrodes by ～50 mV at open circuit under 1 sun illumination and demonstrated comparable electrocatalytic activity.
关键词： photocathodes,silicon nanowires,hydrogen evolution,molybdenum disulfide,zinc oxide nanowires,photoelectrochemical water splitting
更新于2025-09-23 15:22:29
-
Mechanisim investigation on the enhanced and selective photoelectrochemical oxidation of atrazine on molecular imprinted mesoporous TiO2
摘要： In this work, enhanced and selective photoelectrochemical (PEC) oxidation of atrazine was realized on molecular imprinted mesoporous TiO2 (MI-meso-TiO2). The investigation revealed that, for one hand, the surface MI sites could function as surface defects for accelerating the separation of photogenerated holes and electrons, leading to enhanced generation of hydroxyl radicals. For the other hand, the MI sites showed enhanced binding affinity toward atrazine, resulted from the formation of multiple hydrogen bonds and halogen bonds etc., which was testified by in situ ATR-FTIR spectra. It led to the enhanced adsorption and improved local concentration of atrazine on the electrode surface. Both the two factors contributed to the improved PEC oxidation activity for atrazine on MI-meso-TiO2 compared with that on meso-TiO2. Moreover, the high binding affinity between MI sites and atrazine resulted in the selective recognition ability toward atrazine in the presence of the coexisting pollutants, so that selective PEC oxidation of atrazine in complex polluted water samples was successfully achieved on MI-meso-TiO2 with the apparent rate constant of 0.25 h-1, whereas that on meso-TiO2 was only 0.08 h-1. This work provided something new for explaining the selective and enhanced PEC performance on molecular imprinting catalyst.
关键词： mesoporous TiO2,molecular imprint,selective photoelectrochemical oxidation,atrazine
更新于2025-09-23 15:22:29