Electronic Structure Engineering of Carbon Nitride Materials by Using Polycyclic Aromatic Hydrocarbons

The design of charge separation sites under illumination in semiconductors is a standing challenge for their utilization as photo(electro)catalysts. Here, the synthesis of modified carbon nitride materials (CNs) with donor–acceptor (D–A) domains, with altering electronic structure, is reported. To do so, new monomers based on polycyclic aromatic hydrocarbons (PAH)-substituted 1,3,5-triazine were designed, which were then embedded within cyanuric acid–melamine supramolecular assemblies to form CN precursors. The conjugation degree of PAHs was systematically changed, from single benzene ring up to pyrene unit, elucidating the role of the conjugation degree on the morphology, structure and electronic properties as well as photo(electro)catalytic activity. The careful design of the D–A sites results in excellent photocatalytic activity as well as long-term stability for the hydrogen evolution reaction. Moreover, PAH–CNs films exhibit enhanced charge separation, optical absorption, electrochemical surface area and electronic conductivity, leading to an outstanding photoelectrochemical (PEC) activity compared to pristine CN.     

高温水中添加微量Zn（2＋）对Inconel600合金氧化膜半导体性质的影响

核电站采用Zn2＋注入技术减少一回路镍基材料的应力腐蚀和辐射污染.向高温水中添加微量Zn2＋制备Inconel600合金表面氧化膜,用光电化学响应技术和容抗测量技术研究Zn2＋对氧化膜半导体性质的影响.光电化学响应结果表明,氧化膜中不同氧化相的特征带隙宽度分别为Fe2O3 2.2 eV,Cr2O3 3.5 eV,Fex...     

Fabrication of NiO photoelectrodes by aerosol‐assisted chemical vapour deposition (AACVD)

Nanostructured nickel oxide (NiO) photoelectrodes were fabricated with controlled morphology and texture using single‐step aerosol‐assisted chemical vapour deposition (AACVD). The durable one‐step film fabrication process resulted in highly crystalline columnar structure. Texture controlled films were also fabricated from granular to crystalline columnar morphology by controlling the deposition temperature. The thin film electrodes are highly reproducible and possess an optical bandgap of ～3.7 eV and exhibit cathodic photocurrent. (© 2014 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)     

Extended light absorption and enhanced photoelectrochemical activity of palladium‐decorated hematite nanotubes prepared by photodeposition method

Palladium particles were deposited on hematite nanotube surfaces via a facile photodeposition method. Anodization method was then used for direct vertical growth of hematite nanotube arrays (HNTs) on a pretreated iron substrate. Field emission scanning electron microscopy, X‐ray diffraction, diffraction reflection spectroscopy and X‐ray photoelectron spectroscopy analyses were then used to carry out morphological and structural investigations. Compared with the bare HNTs, Pd‐decorated hematite films (Pd/HNTs) exhibit intense visible light absorption and show a red shift of the band edge. Pd/HNTs are more photoelectrochemically active than the non‐decorated films, according to chronoamperometry measurements. Thus, a promising methodology has been developed for the design of a simple and effective photoelectrode for application in photoelectrochemical water splitting systems.     

Improving the stability of photosystem I–based bioelectrodes for solar energy conversion

Isolated photosystem I (PSI) has been integrated into numerous technologies for solar energy conversion. Interest in PSI is a consequence of its high internal quantum efficiency, thermal stability, ease of extraction, and adaptability. While there has been success in improving performance to elevate PSI biohybrid technologies toward a practical realm, the stability of PSI bioelectrodes is also of critical importance. Commercial solar energy conversion technologies are expected to achieve lifetimes of the order of ten years; however, many research-scale PSI bioelectrodes have only been tested for tens of days. Key areas affecting PSI bioelectrode stability include the effects of reactive oxygen species, immobilization strategies, and the environment within solid-state PSI biohybrid photovoltaics. At the current state, further investigation of long-term stability is necessary in enabling the development of PSI bioelectrodes for both photoelectrochemical cells and solid-state biohybrid photovoltaics.     

Poly(ethylene oxide-co-epichlorohydrin)/NaI: a promising polymer electrolyte for photoelectrochemical cells

We have investigated the thermal and ionic conductivity properties of the elastomer poly(ethylene oxide-co-epichlorohydrin) filled with NaI and I₂. The reason for using this composition is its potential application as electrolyte in photoelectrochemical cells. This copolymer was characterized as a function of NaI concentration, temperature and relative humidity. According to the data obtained, the Na⁺ ion interacts with the ethylene oxide repeating units by means of Lewis type acid–base interactions. The empirical Vogel–Tamman–Fulcher equation was used to model the conductivity and temperature relationships, indicating that the conduction occurs in the amorphous phase of the copolymer. The sample with 9.0% (w/w) of NaI presents a conductivity of 1.5×10⁻⁵ S cm⁻¹ in a dry atmosphere (30°C, [H₂O]<1 ppm) and 2.0×10⁻⁴ S cm⁻¹ at 86% relative humidity (22°C).     

激光扫描光电化学显微技术及其应用进展

综述了激光扫描光电化学显微技术及其在研究金属氢化膜、半导体电极表面修饰、光电化学腐蚀和光电活性物质电沉积过程的应用。     

二氧化钛纳米膜电极的形貌和光电化学性质

采用两种不同粒度的国产TiO2纳米材料和进口TiO2P25粉末,以涂覆法分别在导电玻璃基底上制备出TiO2纳米膜电极.通过循环伏安、瞬态光电流时间谱,结合SEM、DRS、XRD等实验手段,分析比较了三种TiO2膜电极的形貌和光电化学性质,探讨了提高和改善电极性能的途径.