Photoelectrochemical Reduction of CO2 over Graphene-Based Composites: Basic Principle, Recent Progress, and Future Perspective

面对日益严重的化石能源消耗和温室效应问题,二氧化碳还原正成为一个重要的全球性研究课题,其通过消耗二氧化碳来生成可用于能源供应的产物。光电催化技术; 同时利用光能和外部电压,是一种用于二氧化碳还原的可行且有效的途径。因为石墨烯具有增强二氧化碳吸附和促进光生电子转移的特性能够提升石墨烯基复合电极; 的性能,所以引入石墨烯用于调优光电催化二氧化碳还原体系已经引起了广泛关注。本篇综述详细陈述了石墨烯基复合材料应用于光电二氧化碳还原的基本原理,电; 极制备方法以及目前的研究进展。我们也对这个蓬勃发展的领域未来可能会遇到的机遇和挑战进行了展望,同时提出了潜在可行的革新策略用于提升光电二氧化碳还; 原方面的研究。In response to aggravated fossil resources consuming and greenhouse effect, CO2 reduction has become a globally important scientific issue because this method can be used to produce value-added feedstock for application in alternative energy supply. Photoelectrocatalysis, achieved by combining optical energy and external electrical bias, is a feasible and promising system for CO2 reduction. In particular, applying graphene in tuning photoelectrochemical CO2 reduction has aroused considerable attention because graphene is advantageous for enhancing CO2 adsorption, facilitating electrons transfer, and thus optimizing the performance of graphene-based composite electrodes. In this review, we elaborate the fundamental principle, basic preparation methods, and recent progress in developing a variety of graphene-based composite electrodes for photoelectrochemical reduction of CO2 into solar fuels and chemicals. We also present a perspective on the opportunities and challenges for future research in this booming area and highlight the potential evolution strategies for advancing the research on photoelectrochemical CO2 reduction.National Natural Science Foundation of China [U1463204, 20903023,; 21173045]; Award Program for Minjiang Scholar Professorship; Natural; Science Foundation of Fujian Province [2012J06003, 2017J07002];; Independent Research Project of State Key Laboratory of Photocatalysis; on Energy and Environment [2014A05]; first Program of Fujian Province; for Top Creative Young Talents; Open Research Project of State Key; Laboratory of Physical Chemistry of Solid Surfaces of Xiamen University; [201519]; Program for Returned High-Level Overseas Chinese Scholars of; Fujian provinc

ULK1/2所构成的信号节点除控制细胞自噬外还控制葡萄糖代谢通路

文章简介在细胞感受到环境中营养物质和生长因子的提供量发生改变后,代谢通路的重编程对于维持此时胞内的稳态是非常重要的过程。ULK1和ULK2是传递外界应激信号至自噬发生的重要整合因子。本项研究发现,在缺少氨基酸和生长因子时,ULK1/2能直接磷酸化多个糖酵解相关的酶,包括己糖激酶(HK)、国家自然科学基金重点项目；国家科技部(973课题)；国家基础科学人才培养基金等的经费支持

Two dimensional inorganic electride-promoted electron transfer efficiency in transfer hydrogenation of alkynes and alkenes

A simple and highly efficient transfer hydrogenation of alkynes and alkenes by using a two-dimensional electride, dicalcium nitride ([Ca2N](+).e(-)), as an electron transfer agent is disclosed. Excellent yields in the transformation are attributed to the remarkable electron transfer efficiency in the electride-mediated reactions. It is clarified that an effective discharge of electrons from the [Ca2N](+).e(-) electride in alcoholic solvents is achieved by the decomposition of the electride via alcoholysis and the generation of ammonia and Ca((OPr)-Pr-i)(2). We found that the choice of solvent was crucial for enhancing the electron transfer efficiency, and a maximum efficiency of 80% was achieved by using a DMF mixed isopropanol co-solvent system. This is the highest value reported to date among single electron transfer agents in the reduction of C-C multiple bonds. The observed reactivity and efficiency establish that electrides with a high density of anionic electrons can readily participate in the reduction of organic functional groups117181sciescopu

The scalable pinacol coupling reaction utilizing the inorganic electride [Ca2N](+)center dot e(-) as an electron donor

The scalable pinacol coupling reaction is realized utilizing the inorganic electride [Ca2N]+·e- as an electron donor in organic solvents. The bond cleavages of the [Ca2N] + layers by methanol play a vital role in transferring anionic electrons to electrophilic aldehydes, accompanying the formation of Ca(OMe) 2 and ammonia. © The Royal Society of Chemistry 2014.114161sciescopu

Dramatically Enhanced Stability of Silver Passivated Dicalcium Nitride Electride: Ag-Ca2N

Electrides have received considerable attention due to their exotic properties. However, the high reactivity with oxygen and moisture immediately decomposed electrides in an ambient air environment. Here we passivated dicalcium nitride electride (Ca2N:e-) with silver via a wet chemical approach (Ag-Ca2N), significantly enhancing stability up to 17 min at room temperature in an ambient air environment. The Ca2N:e- was employed as a reducing agent due to the low work function (2.6 eV), high mobility, and high electron concentration facilitating electron transfer to Ag+ ion in an aprotic cosolvent. Moreover, the noble metal surface passivation (thickness: 55 nm) was achieved with negligible increase in work function of Ag-Ca2N (2.78 eV). The optimized molar ratio of AgNO3/Ca2N:e- was 0.5. The enhanced stability of Ag-Ca2N in organic reaction medium enabled successful aldol condensation reaction outside the glovebox, with a high ��,��-unsaturated ketone yield of 75.4%, without involving environmentally harmful strong acid or base. The enhanced stability and low work function may realize practical economic applications of Ag-Ca2N. © 2018 American Chemical Societ

Birch Reduction of Aromatic Compounds by Inorganic Electride [Ca2N]+•e– in an Alcoholic Solvent: An Analogue of Solvated Electrons

Birch reduction of aromatic systems by solvated electrons in alkali metal-ammonia solutions is widely recognized as a key reaction that functionalizes highly stable pi-conjugated organic systems. In spite of recent advances in Birch reduction with regard to reducing agent and reaction conditions, there remains an ongoing challenge to develop a simple and efficient Birch reaction under mild conditions. Here, we demonstrate that the inorganic electride [Ca2N](+center dot)e(-) promotes the Birch reduction of polycyclic aromatic hydrocarbons (PAHs) and naphthalene under alcoholic solvent in the vicinity of room temperature as a solid-type analogy to solvated electrons in alkali metal ammonia solutions. The anionic electrons from electride [Ca2N](+center dot)e(-) are transferred to PAHs and naphthalene via alcoholysis in a polar cosolvent medium. It is noteworthy that a high conversion yield to the hydrogenated products is ascribed to the extremely high electron transfer efficiency of 98%. This simple protocol utilizing an inorganic electride offers a direct and practical strategy for the reduction of aromatic compounds and provides an outstanding reducing agent for synthetic chemistry © 2018 American Chemical Societ

Hydrotrifluoromethylation and iodotrifluoromethylation of alkenes and alkynes using an inorganic electride as a radical generator

The trifluoromethyl (CF3) group is a staple synthon that can alter the physical and chemical properties of organic molecules. Despite recent advances in trifluoromethylation methods, the development of a general synthetic methodology for efficient and selective trifluoromethylation remains an ongoing challenge motivated by a steadily increasing demand from the pharmaceutical, agrochemical and materials science industries. In this article, we describe a simple, efficient and environmentally benign strategy for the hydrotrifluoromethylation of unactivated alkenes and alkynes through a radical-mediated reaction using an inorganic electride, [Ca2N]þ e, as the electron source. In the transformation, anionic electrons are transferred from [Ca2N]þ e electrides to the trifluoromethylating reagent CF3I to initiate radical-mediated trifluoromethylation. The role of ethanol is pivotal in the transformation, acting as the solvent, an electron-releasing promoter and a hydrogen atom source. In addition, iodotrifluoromethylation of alkynes proceeds selectively upon the control of electride amount.129351sciescopu

Evidence for Anionic Excess Electrons in a Quasi-Two-Dimensional Ca2N Electride by Angle-Resolved Photoemission Spectroscopy

Angle-resolved photoemission spectroscopy (ARPES) study of a layered electride Ca2N was carried out to reveal its quasi-two-dimensional electronic structure. The band dispersions and the Fermi-surface map are consistent with the density functional theory results except for a chemical potential shift that may originate from the high reactivity of surface excess electrons. Thus, the existence of anionic excess electrons in the interlayer region of Ca2N is strongly supported by ARPES. © 2016 American Chemical Society113141sciescopu

Chemoselective Hydrodehalogenation of Organic Halides Utilizing Two-Dimensional Anionic Electrons of Inorganic Electride [Ca₂N]⁺·e^–

Halogenated organic compounds are important anthropogenic chemicals widely used in chemical industry, biology, and pharmacology; however, the persistence and inertness of organic halides cause human health problems and considerable environmental pollution. Thus, the elimination or replacement of halogen atoms with organic halides has been considered a central task in synthetic chemistry. In dehalogenation reactions, the consecutive single-electron transfer from reducing agents generates the radical and corresponding carbanion and thus removes the halogen atom as the leaving group. Herein, we report a new strategy for an efficient chemoselective hydrodehalogenation through the formation of stable carbanion intermediates, which are simply achieved by using highly mobile two-dimensional electrons of inorganic electride [Ca₂N]⁺·e^– with effective electron transfer ability. The consecutive single-electron transfer from inorganic electride [Ca₂N]⁺·e^– stabilized free carbanions, which is a key step in achieving the selective reaction. Furthermore, a determinant more important than leaving group ability is the stability control of free carbanions according to the s character determined by the backbone structure. We anticipate that this approach may provide new insight into selective chemical formation, including hydrodehalogenation