New photocatalysts: Dispersed semiconductor materials with microheterojunctions

We have obtained new semiconductor materials with microheterojunctions by substitution of surface cadmium ions in CdS by Cu(I), Cu(II), and Bi(III) ions. We have shown that the photocatalytic activity of their dispersions in the reaction of evolution of H₂ from alcohol-water mixtures is considerably higher than in the original cadmium sulfide.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 29, No. 3, pp. 270–274, May–June, 1993.We would like to acknowledge Academician V. D. Pokhodenko of the Academy of Sciences of Ukraine for drawing our attention to the prospects for investigation of complex photocatalytic systems based on semiconductors with different types of conductivity.     

Crystal facet engineering of semiconductor photocatalysts: motivations, advances and unique properties

Crystal facet engineering of semiconductors has become an important strategy for fine-tuning the physicochemical properties and thus optimizing the reactivity and selectivity of photocatalysts. In this review, we present the basic strategies for crystal facet engineering of photocatalysts and describe the recent advances in synthesizing faceted photocatalysts, in particular TiO(2) crystals. The unique properties of faceted photocatalysts are discussed in relation to anisotropic corrosion, interaction dependence of adsorbates, photocatalytic selectivity, photo-reduction and oxidation sites, and photocatalytic reaction order. Ideas for future research on crystal facet engineering for improving the performance of photocatalysts are also proposed.     

半导体/石墨烯复合光催化剂的制备及应用

首先分析了石墨烯和半导体光催化剂的特点,以及二者复合后可能具有的优越性质,接着介绍了石墨烯和半导体复合光催化剂的制备方法,归纳了石墨烯增强半导体光催化的机理,然后阐述了复合光催化剂在降解有机污染物、光催化分解水产氢、光催化还原CO2制有机燃料和光催化灭菌四个典型的应用,最后对半导体/石墨烯复合光催化剂未来的发展趋势提出了展望.     

石墨烯基无机纳米复合材料*

石墨烯(graphene)是近年被发现和合成的一种新型二维平面纳米碳质材料。由于其新奇的物理和化学性质,石墨烯已经成为了备受瞩目的科学新星,是纳米材料领域的一大研究热点。在石墨烯的研究中,基于石墨烯的无机纳米复合材料是石墨烯迈向实际应用的一个重要方向。本文在简要介绍石墨烯的结构、性质和制备方法的基础上,重点就近年来以石墨烯为基体的无机物（主要包括金属和半导体）纳米复合材料的合成和应用作一述评,并对石墨烯基无机纳米复合材料的研究和发展方向作了展望。     

Graphene-based electrochemical supercapacitors

Graphenes prepared by three different methods have been investigated as electrode materials in electrochemical supercapacitors. The samples prepared by exfoliation of graphitic oxide and by the transformation of nanodiamond exhibit high specific capacitance in aq. H₂SO₄, the value reaching up to 117 F/g. By using an ionic liquid, the operating voltage has been extended to 3·5 V (instead of 1 V in the case of aq. H₂SO₄), the specific capacitance and energy density being 75 F/g and 31·9 Wh kg⁻¹ respectively. This value of the energy density is one of the highest values reported to date. The performance characteristics of the graphenes which are directly related to the quality, in terms of the number of layers and the surface area, are superior to that of single-walled and multi-walled carbon nanotubes.     

Graphene-based hemostatic sponge

Graphene-based sponge is a novel hemostatic material prepared by chemical cross-link of graphene oxide. It has a fast fluid absorption capacity to quickly absorb blood from wounds, activate clotting pathways, and achieve rapid hemostasis. In addition, graphene-based sponge is also a good platform carrier.It can be prepared by organic cross-linking, compounding with inorganic clay, and adding bioactive factors to enhance coagulation stimulation. By these methods, the hemostatic performance of the...     

仿鲍鱼壳石墨烯多功能纳米复合材料

石墨烯具有力学性能高、电导率优异等特点,然而单层石墨烯纳米片在组装成为宏观纳米复合材料的过程中,往往会出现片层团聚、界面作用弱、无规取向等问题,导致宏观石墨烯纳米复合材料性能远低于单片石墨烯。因此,如何将微观石墨烯纳米片层的高性能在宏观纳米复合材料中体现出来,是目前研究的热点和难点。本专论结合目前石墨烯纳米复合材料的研究现状,简要讨论了受天然鲍鱼壳的“砖-泥”结构的启发,仿生构筑高性能石墨烯纳米复合材料的最新研究进展。并对本课题组在仿鲍鱼壳石墨烯多功能纳米复合材料领域近年来的工作进行介绍,包括石墨烯纤维、薄膜和块材等多种宏观石墨烯纳米复合材料,系统总结构筑仿鲍鱼壳结构和反鲍鱼壳结构两种策略,在一定程度上解决了石墨烯在组装过程中的科学问题。同时,详细阐述了仿鲍鱼壳石墨烯多功能纳米复合材料的增强增韧机制和功能化策略,分析了今后研究工作中可能遇到的问题,并展望了未来的发展趋势。     

A short review on recent progress of Bi/semiconductor photocatalysts: The role of Bi metal

Bi/semiconductor photocatalysts have extensively been applied in the production of hydrogen, CO₂ reduction and environmental remediation in recent years. This short review summarizes the role of Bi metal as a plasma photocatalyst and cocatalyst. As a cocatalyst, Bi metal can be electron/hole trappers, charge transfer mediators, or oxygen vacancy coordinators. In addition, the preparation methods of the Bi/semiconductor photocatalysts are also reviewed. Challenges and future research directions related to Bi/semiconductor photocatalysts are discussed and summarized, including the use of advanced characterization techniques to refine the reaction mechanism, the difficulties of preparing Bi single atom catalyst, and the improvement of the reduction ability of Bi-based photocatalysts. This review helps understand the reaction mechanisms of the composite photocatalytic systems containing Bi metal and proposes new perspectives for designing the photocatalysts which can control air pollution via a reductive process.     

基于石墨烯的光学生物传感器的研究进展

近年来,随着石墨烯研究热潮的兴起,将石墨烯用于生物及化学检测的工作也日益增多.本文着重介绍了基于石墨烯及氧化石墨烯(GO)的光学生物传感器,特别是基于石墨烯的荧光共振能量转移(FRET)传感器以及比色法传感器的设计思想和传感特性.     

Zeolite-based photocatalysts

The compartmentalised intracrystalline void space of zeolites are specially suited to incorporate and organise photoactive guests that can be used as photocatalysts. The rigid micropores allow assembly of multicomponent systems comprising of antenna and relays reminiscent of natural photosynthetic centers. Besides inorganic metal oxide clusters, zeolites as host are particularly attractive to construct organic photocatalysts since the guest becomes significantly stabilized by incorporation. This review gives special emphasis to the commercial and potential application of photocatalysts.     

Selective CO2 conversion to formate conjugated with H2O oxidation utilizing semiconductor/complex hybrid photocatalysts

Photoelectrochemical reduction of CO(2) to HCOO(-) (formate) over p-type InP/Ru complex polymer hybrid photocatalyst was highly enhanced by introducing an anchoring complex into the polymer. By functionally combining the hybrid photocatalyst with TiO(2) for water oxidation, selective photoreduction of CO(2) to HCOO(-) was achieved in aqueous media, in which H(2)O was used as both an electron donor and a proton source. The so-called Z-scheme (or two-step photoexcitation) system operated with no external electrical bias. The selectivity for HCOO(-) production was >70%, and the conversion efficiency of solar energy to chemical energy was 0.03-0.04%.     

石墨烯基催化剂的设计合成与电催化应用

为了解决能源匮乏和环境污染的问题,研究人员正致力于寻找清洁可持续的新能源。 其中,氧气还原、氧气析出、析氢反应等是紧密联系新型清洁能源获取和存贮的重要电化学反应。 为了提高其能量转化效率,电催化剂(如碳载铂Pt/C)被广泛地用于降低其反应活化能、提高能量转化效率。 近年来,石墨烯作为一种具有高比表面积和优异导电性的二维碳材料受到了广泛关注。 通过表面杂原子掺杂、缺陷调控和引入催化活性组分等方式,获得了催化性能与贵金属催化剂相媲美,且低价格和高稳定性的非贵金属石墨烯基催化材料。 针对氧气还原、氧气析出和析氢反应在燃料电池、金属-空气电池和电催化水分解中的应用,本文概括综述了通过表/界面结构性质调控提高石墨烯电催化性能和稳定性,获得具有双功能或复合催化性能的石墨烯基催化剂的最新研究进展。 最后总结和展望了亟待解决的问题及未来的发展趋势。     

石墨烯基海绵在止血领域的研究进展

石墨烯基海绵是一类新型的外伤止血材料, 由二维纳米片层构筑形成, 具有多级孔道结构、 快速液体吸收能力及易于表面功能化等特性, 可作为平台式载体实现多功能复合, 在外伤止血领域表现出良好的应用前景. 本文对石墨烯基海绵的外伤止血应用与机制研究进行了综述, 并对其发展前景进行了展望.     

Graphene-based materials for polymer solar cells

Due to the remarkable electronic, optical, thermal, and mechanical properties, graphene-based materials have shown great potential in a wide range of technique applications. Particularly, the high transparency, conductivity, flexibility, and abundance make graphene materials highly attractive for polymer solar cells (PSCs). Graphene-based materials have been regarded as one promising candidate used in various parts in PSCs not only as electrodes, but also as interfacial layers and active layers with an aim to boost the power conversion efficiency of the devices. In this review, we summarize the recent progress about the design and synthesis of graphene-based materials for efficient PSCs along with the related challenges and future perspectives.     

Graphene-based field effect transistors as biosensors

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Laponite-supported titania photocatalysts

This study builds on previous results published on the synthesis and characterization of laponite-supported titania photocatalysts. Titania nanocrystals are prepared prior to addition to the clay dispersion, by a sol-gel synthesis incorporating a microwave hydrothermal step. In addition to previously examinations with XRD, TEM, and FT-IR, the samples are further characterized with SEM, 29Si NMR, and BET N2 sorption to gain additional insight into the effect of TiO2 concentration and surface area on the photoactivity of the samples.     

Solar hydrogen production. Significant effect of Na2CO3 addition on water splitting using simple oxide semiconductor photocatalysts

Recent progress in photocatalytic decomposition of water to H₂ and O₂ using simple oxide semiconductor catalysts has been reviewed. Addition of Na₂CO₃ to Pt/TiO₂ suspension in water enhanced the stoichiometric decomposition significantly. This Na₂CO₃ addition method has been proved to be very useful to accelerate water splitting over various kinds of oxide semiconductor photocatalysts. The role of CO₃ ^2? anion on the acceleration of water splitting was clarified. Finally, it was firstly demonstrated in the world that water was decomposed efficiently and stoichiometrically to H₂ and O₂ using a 3 wt% NiOx/TiO₂ photocatalyst under real solar light irradiation in Tsukuba, Japan by this Na₂CO₃ addition method.