- 标题
- 摘要
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- 实验方案
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Diversity of TiO <sub/>2</sub> : Controlling the Molecular and Electronic Structure of Atomic-Layer-Deposited Black TiO <sub/>2</sub>
摘要： Visually black, electrically leaky, amorphous titania (am-TiO2) thin films were grown by atomic layer deposition (ALD) for photocatalytic applications. Broad spectral absorbance in the visible range and exceptional conductivity are attributed to trapped Ti3+ in the film. Oxidation of Ti3+ upon heat treatment leads to a drop in conductivity, a color change from black to white and crystallization of am-TiO2. ALD grown black TiO2, without any heat treatment, is subject to dissolution in alkaline photoelectrochemical conditions. The best photocatalytic activity for solar water splitting is obtained for completely crystalline white TiO2.
关键词： atomic layer deposition,photocatalysis,titanium dioxide,protecting overlayers,crystallization,oxide defects,water splitting
更新于2025-09-23 15:23:52
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Scaling up electrodes for photoelectrochemical water splitting: fabrication process and performance of 40 cm2 LaTiO2N photoanodes
摘要： A scalable process for particle-based photoanodes is developed. The electrodes are versatilely made of photocatalytically active semiconductor particles, here LaTiO2N, and optionally coated with co-catalysts and protecting components, all immobilized on a conducting substrate. The involved fabrication steps are restricted to scalable processes like electrophoretic deposition, annealing in air and dip coating. Special care is taken to ensure charge transport in between particles and to the substrate by adding conducting connectors. Adapting the fabrication steps, the geometrical electrode dimension is increased from the size of a typical lab electrode of 1 cm2 to 40 cm2. The quality of the scale up process is characterized by comparing the photoanodes in terms of thickness, light absorption properties and morphology. For several compositions, the electrochemical performance of both electrode sizes is assessed by measuring photocurrents and Faraday efficiencies. The comparison revealed a complex upscaling behavior and showed that photoelectrode size affected performance already on the 0.1 m scale.
关键词： photoelectrodes,energy conversion,LaTiO2N,electrode size,water splitting
更新于2025-09-23 15:22:29
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The cost-effective deposition of ultra-thin titanium(IV) oxide passivating layers for improving photoelectrochemical activity of SnS electrodes
摘要： The structures of tin monosulfide (SnS) with the surface modified by ultrathin titanium(IV) oxide layers for potential photoinduced water splitting were successfully fabricated. SnS thin films were deposited onto glass/Mo substrates using high vacuum evaporation (HVE) method, and then a simple and cost-effective deposition-annealing cycling process was used to prepare titanium(IV) oxide passivated SnS structures. The resulting compositional properties were studied using X-ray diffractometry (XRD), Raman spectroscopy, high resolution scanning electron microscopy (SEM) and energy-dispersive X-ray analysis (EDX). The effects of titanium(IV) oxide layers on the photo-electrochemical (PEC) activity of fabricated p-type SnS thin-film electrodes were examined in this study. The SnS layers passivated with titanium(IV) oxide exhibited reducing the SnS-electrolyte interface resistance, increasing the photocurrent and improving the efficiency of PEC cells as deleterious reactions are inhibited. The various electrochemical methods such as current-voltage measurements, cyclic voltammetry, and electrochemical impedance spectroscopy were used to characterise and analyse SnS structures modified by titanium(IV) oxide.
关键词： Photocathode,Solar energy,Tin sulfide,Titanium dioxide,Water splitting
更新于2025-09-23 15:22:29
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Reaction Packaging CoSe <sub/>2</sub> Nanoparticles in N-Doped Carbon Polyhedra with Bifunctionality for Overall Water Splitting
摘要： Water electrolysis is a promising approach for green and large-scale hydrogen production; however, there are still challenges for developing efficient and stable bi-functional electrocatalysts towards the hydrogen and oxygen evolution reactions. Herein, zeolitic imidazolate framework-67 (ZIF67) was used as the precursor for the construction of CoSe2 nanoparticles trapped in N-doped carbon polyhedra (NC). Among as-obtained CoSe2-NC hybrid, highly active CoSe2 nanoparticles in sizes of 10-20 nm are encapsulated in N-doped few-layer carbon shell, avoiding their easy aggregations of CoSe2 nanoparticles as well as enhancing the long-term stability. The unique nanostructured CoSe2-NC hybrid with a hierarchical porosity and 3D conductive framework thus fully exerts outstanding bi-functional catalytic activity of CoSe2 centers. As a result, the CoSe2-NC hybrid as bi-functional catalysts for overall water splitting delivers a high current density of 50 mA cm-2 with applied voltage of ~1.73 V in alkaline electrolyte, with a promising stability over 50000 s.
关键词： selenide reaction,ZIF67,bifunctional electrocatalyst,overall water splitting,carbon polyhedra
更新于2025-09-23 15:22:29
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Photocatalytic Overall Water Splitting on RuO <sub/>2</sub> -loaded Sm <sup>3+</sup> -doped CeO <sub/>2</sub> with Heterogenous Doping Structure
摘要： Photocatalytic overall water splitting into hydrogen and oxygen on RuO2-loaded Sm3+-doped CeO2 was examined. Pure CeO2 showed a negligible small activity, however Sm3+ doped CeO2 with heterogeneous doping structure synthesized by solid state reaction exhibited an efficient activity. Whereas, Sm3+-doped CeO2 with homogeneous doping structure showed little activity when prepared by co-precipitation method. In this study, relation between photocatalytic activity and surface doping structure was investigated.
关键词： Heterogeneous doping structure,Semiconductor photocatalyst,Overall water splitting
更新于2025-09-23 15:22:29
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A Photoresponsive Rutile TiO <sub/>2</sub> Heterojunction with Enhanced Electron-Hole Separation for High-Performance Hydrogen Evolution
摘要： Rutile titanium dioxide (TiO2) is a promising photocatalyst due to its high thermodynamic stability and few intragrain defects. However, it has not yet achieved photocatalytic activity comparable to that of anatase TiO2 owing to its higher recombination rate of electron–hole pairs. To effectively separate the electron–hole pairs in rutile TiO2, a facet heterojunction (FH) structure to prolong the lifetime of the photogenerated electrons is proposed. Ultrathin TiO2 nanosheets with different facets are coated in situ onto TiO2 nanorod (NR) substrates, where FHs are built among the nanosheets as well as between the nanosheets and NR substrates. The as-prepared rutile TiO2, with an FH structure (FH-TiO2), serves as an effective photocatalyst for water splitting. More than 45 and 18 times higher photogenerated current density and H2 production rate, respectively, are obtained compared to those of pure rutile TiO2 NRs. Moreover, FH-TiO2 delivers a 0.566 mmol g?1 h?1 H2 production rate even in pure water. This study offers important insights into the rational design of rutile TiO2 structures for highly efficient photocatalytic reactions.
关键词： charge separation,rutile TiO2,facet heterojunction,water splitting
更新于2025-09-23 15:22:29
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The role of synthesis conditions for structural defects and lattice strain in β-TaON and their effect on photo- and photoelectrocatalysis
摘要： The importance of the synthesis conditions on the structural and photocatalytic properties of tantalum oxide nitride was investigated by comparing two variants of phase-pure β-TaON obtained from application of two different synthesis routes, leading to one unstrained and one heavily anisotropically microstrained β-TaON as shown by XRD-based Rietveld refinement. HRTEM images reveal the origin of the strain to be lattice defects such as stacking faults. The strained β-TaON was found to be the clearly less active semiconductor in photochemical and photoelectrochemical water oxidation. The lattice defects are assumed to act as charge carrier traps hindering the photo-generated holes to be displaced to the reaction sites at the surface.
关键词： tantalum oxide nitride,photocatalysis,photoelectrochemistry,water splitting,structural defects
更新于2025-09-23 15:22:29
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Ni doped noble-metal-free CdZnNiS photocatalyst for high-efficient photocatalytic hydrogen evolution reduction by visible light driving
摘要： In this paper, we report a method that the transition element nickel is doped into the interstitial position of CdZnS (CZS) nanoparticles for their photocatalytic hydrogen evolution activity boosting. It is demonstrated that CdZnNiS nanocrystalline materials (with 0.5 wt% of Ni) could achieve the highest photocatalytic H2-evolution activity of 25.4 mmol·g?1·h?1 in sulfide and sulfite solution under visible light which value is 1.16 times higher than that of Pt modified CdZnS particles (with 3 wt% of Pt). This work evidences the possibility of substitution of noble metal cocatalyst by adding a suitable inexpensive Ni to achieve high-efficient visible light driven water splitting hydrogen production.
关键词： Semiconductors,CdZnNiS nanocrystalline materials,Noble-metal-free cocatalyst,Gap doping,Nanocomposites,Water splitting
更新于2025-09-23 15:22:29
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Network Structured CuWO4/BiVO4/Co-Pi Nanocomposite for Solar Water Splitting
摘要： A network structured CuWO4/BiVO4 nanocomposite with a high specific surface area was prepared from CuWO4 nanoflake (NF) arrays via a method that combined drop-casting and thermal annealing. The obtained CuWO4/BiVO4 exhibited high catalytic activity toward photoelectrochemical (PEC) water oxidation. When cobalt phosphate (Co-Pi) was coupled with CuWO4/BiVO4, the activity of the resulting CuWO4/BiVO4/Co-Pi composite for the oxygen evolution reaction (OER) was further improved. The photocurrent density (Jph) for OER on CuWO4/BiVO4/Co-Pi is among the highest reported on a CuWO4-based photoanode in a neutral solution. The high activity for the PEC OER was attributed to the high specific surface area of the composite, the formation of a CuWO4/BiVO4 heterojunction that accelerated electron–hole separation, and the coupling of the Co-Pi co-catalyst with CuWO4/BiVO4, which improved the charge transfer rate across composite/solution interface.
关键词： copper tungstate,cobalt phosphate,oxygen evolution reaction,bismuth vanadate,photoelectrochemical water splitting
更新于2025-09-23 15:22:29
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Nanoporous water oxidation electrodes with a low loading of laser-deposited Ru/C exhibit enhanced corrosion stability
摘要： For the oxidation of water to dioxygen, oxide-covered ruthenium metal is known as the most efficient catalyst, however, with limited stability. Herein, we present a strategy for incorporating a Ru/C composite onto a novel nanoporous electrode surface with low noble metal loading and improved stability. The Ru/C is coated on the pore walls of anodic alumina templates in a one-step laser-induced deposition method from Ru3(CO)12 solutions. Scanning electron microscopy proves the presence of a continuous Ru/C layer along the inner pore walls. The amorphous material consists of metallic Ru incorporated in a carbonaceous C matrix as shown by X-ray diffraction combined with Raman and X-ray photoelectron spectroscopies. These porous electrodes reveal enhanced stability during water oxidation as compared to planar samples at pH 4. Finally, their electrocatalytic performance depends on the geometric parameters and is optimized with 13 μm pore length, which yields 2.6 mA cm?2, or 49 A g?1, at η = 0.20 V.
关键词： ruthenium catalyst,nanostructures,water splitting,electrochemistry,noble metals
更新于2025-09-23 15:22:29