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In situ optical spectroscopic understanding of electrochemical passivation mechanism on sol–gel processed WO_(3) photoanodes

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Journal of Energy Chemistry 2022年第8期31卷 20-28,I0002页

作者： Jianyong Feng Xin Zhao Bowei Zhang Zhong Chen zhaosheng li Yizhong Huang Collaborative Innovation Center of Advanced Microstructures National Laboratory of Solid State MicrostructuresCollege of Engineering and Applied SciencesNanjing UniversityNanjing 210093JiangsuChina School of Materials Science and Engineering Nanyang Technological UniversitySingapore 639798Singapore

A prevailing understanding on electrochemical activation of photoelectrodes is that electrochemical treatment leads to increased charge carrier densities thereby improved photoelectrode performances.Contrary to this understanding,in this study enhanced photoactivity of WO_(3) photoanode upon electrochemical treatment is ascribed to an extraordinary mechanism of surface trap passivation.The associated mechanism is analyzed by in situ optical spectroscopy,using which the optical property changes of WO_(3) electrode during electrochemical treatment are monitored.The results suggest surface W^(5+)species,the origin of surface traps on WO_(3) photoanodes,are converted to W^(6+) ions by electrochemical treatment.This study demonstrates the particular ability of the electrochemical strategy to passivate surface traps of photoanodes,and also shows the advantages of in situ optical spectroscopy to investigate the real-time electronic structure variations of electrodes during electrochemical treatment.

关键词： In situ optical spectroscopy Electrochromism Surface trap Solar water splitting Tungsten oxide Hydrogen

Paving the road toward the use of β-Fe2O3 in solar water splitting: Raman identification, phase transformation and strategies for phase stabilization

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National Science Review 2020年第6期7卷 1059-1067页

作者： Ningsi Zhang Xin Wang Jianyong Feng Huiting Huang Yongsheng Guo zhaosheng li Zhigang Zou Collaborative Innovation Center of Advanced Microstructures National Laboratory of Solid State Microstructures College of Engineering and Applied Sciences Nanjing University Jiangsu Key Laboratory of Nano Technology Nanjing University

Although β-Fe2O3has a high theoretical solar-to-hydrogen efficiency because of its narrow band gap, the study of β-Fe2O3photoanodes for water splitting is elusive as a result of their metastable nature. Raman identification of β-Fe2O3is theoretically and experimentally investigated in this study for the first time, thus clarifying the debate about its Raman spectrum in the literature. Phase transformation of β-Fe2O3toα-Fe2O3was found to potentially take place under laser and electron irradiation as well as annealing.Herein, phase transformation of β-Fe2O3to α-Fe2O3was inhibited by introduction of Zr doping, andβ-Fe2O3was found to withstand a higher annealing temperature without any phase transformation. The solar water splitting photocurrent of the Zr-doped β-Fe2O3photoanode was increased by 500% compared to that of the pure β-Fe2O3photoanode. Additionally, Zr-doped β-Fe2O3exhibited very good stability during the process of solar water splitting. These results indicate that by improving its thermal stability,metastable β-Fe2O3film is a promising photoanode for solar water splitting.

关键词： solar energy conversion metastable phase phase transformation iron oxide photoelectrochemical water splitting

Extraterrestrial artificial photosynthetic materials for in-situ resource utilization

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National Science Review 2021年第8期8卷 108-133页

作者： liuqing Yang Ce Zhang Xiwen Yu Yingfang Yao zhaosheng li Congping Wu Wei Yao Zhigang Zou Eco-Materials and Renewable Energy Research Center(ERERC) Jiangsu Key Laboratory for Nano TechnologyNational Laboratory of Solid State MicrostructuresSchool of PhysicsNanjing University Collaborative Innovation Center of Advanced Microstructures College of Engineering and Applied SciencesNanjing University Kunshan Innovation Institute of Nanjing University Macau Institute of Systems Engineering Macau University of Science and Technology School of Science and Engineering The Chinese University of Hong Kong Qian Xuesen Laboratory of Space Technology China Academy of Space Technology Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology

Aerospace milestones in human history, including returning to the moon and manned Martian missions,have been implemented in recent years. Space exploration has become one of the global common goals, and to ensure the survival and development of human beings in the extraterrestrial extreme environment has been becoming the basic ability and technology of manned space exploration. For the purpose of fulfilling the goal of extraterrestrial survival, researchers in Nanjing University and the China Academy of Space Technology proposed extraterrestrial artificial photosynthesis(EAP) technology. By simulating the natural photosynthesis of green plants on the Earth, EAP converts CO/HO into fuel and Oin an in-situ,accelerated and controllable manner by using waste COin the confined space of spacecraft, or abundant COresources in extraterrestrial celestial environments, e.g. Mars. Thus, the material loading of manned spacecraft can be greatly reduced to support affordable and sustainable deep space exploration. In this paper, EAP technology is compared with existing methods of converting CO/HO into fuel and Oin the aerospace field, especially the Sabatier method and Bosch reduction method. The research progress of possible EAP materials for in-situ utilization of extraterrestrial resources are also discussed in depth. Finally,this review lists the challenges that the EAP process may encounter, which need to be focused on for future implementation and application. We expect to deepen the understanding of artificial photosynthetic materials and technologies, and aim to strongly support the development of manned spaceflight.

关键词： solar energy extraterrestrial survival artificial photosynthesis CO_2 reduction oxygen evolution

Effects of ginsenoside on brain-derived neurotrophic factor and tyrosine kinase B mRNA expression in the hippocampal formation of aged rats

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Neural Regeneration Research 2008年第7期3卷 723-727页

作者： Hong Lai Wensu liu zhaosheng li Haihua Zhao Yongli Lü Department of Anatomy College of Basic Medical Science China Medical University Shenyang 110001 Liaoning Province China School of Geophysics and Information Technology China University of Geosciences Beijing

BACKGROUND： There are a limited number of studies involving the effects of ginsenosides, the active component of ginseng, on expression of hippocampal TrkB mRNA in aged rats. OBJECTIVE： To observe expression of brain-derived neurotrophic factor （BDNF） and tyrosine kinase B （TrkB） mRNA in the hippocampal formation of aged rats, as well as changes after ginsenoside administrated. DESIGN, TIME AND SETTING： A randomized, controlled experiment was performed at the Department of Anatomy, College of Basic Medical Sciences, China Medical University in March 2005. MATERIALS： A total of 39 female, Wistar rats were randomly divided into 3 groups （n = 13 each）： young （3-5 months old）, aged （27 months old）, and ginsenoside group （received 25mg/kg/d ginsenoside in the drinking water between 17 and 27 months of age）. METHODS： Following anesthesia, the rats were exsanguinated and perfused transcardially with chilled, heparinized, 0.9% saline. The brains were removed and post-fixed in 40 g/L paraformaldehyde/phosphate buffer for 20 minutes, and further incubated in 30% sucrose/phosphate buffer overnight. MAIN OUTCOME MEASURES： In situ hybridization, immunohistochemistry, and image analysis were used to investigate expression of BDNF and TrkB mRNA in the hippocampal formation. RESULTS： The expression levels of BDNF in the hippocampal CA3 and CA1 of aged rats was significantly less than the young group （t = 2.879, 1.814, 1.984, P 〈 0.05）. BDNF expression was significantly greater in the dentate gyrus of the ginsenoside group, compared with the aging group （t = 1.943, P 〈 0.01）. The expression of TrkB mRNA in the hippocampal CA3, CA1, and dentate gyrus of aged rats was less than the young group （t = 3.540, 3.629, 17.905, P 〈 0.01）. TrkB mRNA expression in the CA3 region and dentate gyrus of the ginsenoside group was significantly greater compared with the aging group （t = 1.293, 3.386, P 〈 0.05, 0.01 ）. CONCLUSION： BDNF and TrkB mRNA expression in the hippocampal formation were reduced in the aged group. However, ginseno

关键词： ginsenosides brain-derived neurotrophic factor tyrosine kinase B hippocampus

Effective fabrication of porous Au-Ag alloy nanorods for in situ Raman monitoring catalytic oxidation and reduction reactions

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Journal of Materials Science & Technology 2021年第32期91卷 262-269页

作者： Shanlin Ke Caixia Kan Xingzhong Zhu Changshun Wang Weijian Gao zhaosheng li Xiaoguang Zhu Daning Shi College of Science Nanjing University of Aeronautics and AstronauticsNanjing 210016China Key Laboratory of Aerospace Information Materials and Physics Ministry of Industry and Information TechnologyNanjing 210016China National Laboratory of Solid State Microstructures Nanjing UniversityNanjing 210093China Institute of Solid State Physics Chinese Academy of SciencesHefei 230031China Key Laboratory for Intelligent Nano Materials and Devices of the Ministry of Education Nanjing 210016China

Porous metal nanostructures exhibit excellent catalytic properties due to their high surface-to-volume ratios and abundant catalytic active sites. However, it is still challenging to control nanopores density and structural features in a facile route and the preparation of porous alloy nanorods for catalytic application has not been well explored. In this work, we demonstrate a synthetic strategy to fabricate highly porous Au–Ag alloy nanorods(P-Au Ag NRs) by critically dealloying Ag atoms from homogeneous solid Au–Ag alloy nanorods(Au Ag NRs). Combining the merits of the tunable plasmonic properties of noble metal nanorods, excellent stabilities of alloys, and superior catalytic activities of porous structures, we use the P-Au Ag NRs as a Raman probe for the in situ monitoring of the catalytic oxidation of 3,3',5,5' tetramethylbenzidine(TMB) and reduction of 4-nitrothiophenol(4-NTP). We also compare their compositiondependent catalytic activities. The results show that P-Au Ag NRs possess superior chemical stability and higher catalytic activity than those of core-shell structures due to synergistic structural and chemical mechanisms. This strategy provides a predictive design approach for the next-generation alloy catalysts with high-performance.

关键词： Catalysis Porous Au-Ag alloy nanorod High-index facets Raman monitoring Oxidation and reduction

Exploring facile strategies for high-oxidation-state metal nitride synthesis: carbonate-assisted one-step synthesis of Ta_3N_5 films for solar water splitting

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Science Bulletin 2018年第21期63卷 1404-1410页

作者： Tao Fang Huiting Huang Jianyong Feng Yingfei Hu Yongsheng Guo Shiying Zhang zhaosheng li Zhigang Zou Collaborative Innovation Center of Advanced Microstructures National Laboratory of Solid State Microstructures Department of Physics Nanjing University College of Engineering and Applied Sciences Nanjing University Hunan Key Laboratory of Applied Environmental Photocatalysis Changsha University

Metal nitrides are widely studied due to their outstanding physical properties, including high hardness,high thermal and chemical stability, low electrical resistivity etc. Generally, metal nitrides can be obtained from the direct reaction of metal and ammonia/nitrogen. However, some of the metal nitrides,such as Ta_3N_5, cannot be synthesized by direct nitridation of metals. To achieve Ta_3N_5, high-oxidationstate Ta precursors like Ta_2O_5, NaTaO_3, TaS_3, K_6Ta_(10.8)O_(30), Ta(N(CH_3)_2)_5 and TaCl_5 have to be employed,which is a time-consuming and laborious process with the possibility of introducing undesirable impurities. Here taking Ta_3N_5 as an example, a facile carbonate-assisted one-step nitridation method is proposed, which enables the direct synthesis of high-oxidation-state metal nitride films from metal precursors under ammonia flow. The mechanism of the nitridation process has been studied, which carbon dioxide released from carbonates decomposition reacts with metallic Ta and assists the one-step conversion of metallic Ta to Ta_3N_5. The as-prepared Ta_3N_5 film, after modified with NiFe layered double hydroxide, exhibits promising water splitting performance and stability. This method avoids the preoxidation process of metal precursors in high-oxidation-state metal nitride synthesis, and may facilitate the direct fabrication of other important metal nitrides besides Ta_3N_5.

关键词： Metal nitrides Carbonate-assisted One-step conversion Ta3N5 films Photoelectrochemical Solar water splitting

Photocatalysis:an overview of recent developments and technological advancements

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Science China Chemistry 2020年第2期63卷 149-181页

作者： Yuanxing Fang Yun Zheng Taofang Yong Chen Yaodong Zhu Qing liang Hua Sheng zhaosheng li Chuncheng Chen Xinchen Wang State Key Laboratory of Photocatalysis on Energy and Environment College of ChemistryFuzhou UniversityFuzhou 350116China Key Laboratory of Molecular Designing and Green Conversions Fujian Province UniversityCollege of Materials Science and EngineeringHuaqiao UniversityXiamen 361021China Collaborative Innovation Center of Advanced Microstructures National Laboratory of Solid State MicrostructuresCollege of Engineering and Applied SciencesNanjing UniversityNanjing 210093China Key Laboratory of Photochemistry CAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Photocatalysis,which is the catalyzation of redox reactions via the use of energy obtained from light sources,is a topic that has garnered a lot of attention in recent years as a means of addressing the environmental and economic issues plaguing society today.Of particular interest are photosynthesis can potentially mimic a variety of vital reactions,many of which hold the key to develop sustainable energy economy.In light of this,many of the technological and procedural advancements that have recently occurred in the field are discussed in this review,namely those linked to:(1)photocatalysts made from metal oxides,nitride,and sulfides;(2)photocatalysis via polymeric carbon nitride(PCN);and(3)general advances and mechanistic insights related to TiO2-based catalysts.The challenges and opportunities that have arisen over the past few years are discussed in detail.Basic concepts and experimental procedures which could be useful for eventually overcoming the problems associated with photocatalysis are presented herein.

关键词： photocatalysis carbon nitride metal oxides metal nitride metal sulfide mechanism TiO2

Insight into the influence of high temperature annealing on the onset potential of Ti-doped hematite photoanodes for solar water splitting

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Chinese Chemical Letters 2018年第6期29卷 791-794页

作者： Yaodong Zhu Qinfeng Qian Guozheng Fan Zhili Zhu Xin Wang zhaosheng li Zhigang Zou Collaborative Innovation Center of Advanced Microstructures National Laboratory of Solid State Microstructures and College of Engineering and Applied Sciences Nanjing University

For Ti-doped hematite photoanodes, high temperature annealing drastically increases the water oxidation plateau photocurrent, but also induces an anodic shift of onset potential by about 100 m V, thus hindering the performance under low applied bias. To the best of our knowledge, the effects of high temperature annealing on the onset potential have been rarely studied. Herein, both X-ray photoelectron spectroscopy（XPS） measurements and theoretical calculations indicated that the increase of surface Ti/Fe atomic ratio after high temperature annealing decreased the adsorption capacity of hydroxide ions on the hematite surface. Subsequently, the flatband potential（i.e., the theoretical onset potential） of Ti doped hematite photoanodes positively shifted, which was supported by the Mott-Schottky measurements.

关键词： Onset potential Hematite Ti doping High temperature annealing Flatband potential DFT calculation

异钩藤碱调节EGFR/FAK信号通路对肝癌细胞增殖、迁移和5-FU耐药性的影响

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药物评价研究 2024年第6期47卷 1267-1274页

作者：李海燕栗昭生赵龙金春花张鼐鹏牡丹江医学院附属红旗医院药学部牡丹江医学院第一临床医学院牡丹江医学院附属红旗医院神经内科牡丹江医学院附属红旗医院普外二科

目的探讨异钩藤碱调节表皮生长因子受体（EGFR）/局部黏着斑激酶（FAK）信号通路对肝癌细胞增殖、迁移和5-氟尿嘧啶（5-FU）耐药性的影响。方法取对数生长期的HepG2细胞，分为对照组，异钩藤碱低、中、高浓度(32.5、65.0、130.0μmol... 详细信息

目的探讨异钩藤碱调节表皮生长因子受体（EGFR）/局部黏着斑激酶（FAK）信号通路对肝癌细胞增殖、迁移和5-氟尿嘧啶（5-FU）耐药性的影响。方法取对数生长期的HepG2细胞，分为对照组，异钩藤碱低、中、高浓度(32.5、65.0、130.0μmol·L-1)组，异钩藤碱(130μmol·L-1)+EGFR激活剂NSC228155(2μmol·L-1)组；对数生长期的5-FU耐药肝癌细胞系HepG2/5-FU分为对照组、异钩藤碱(130μmol·L-1)组、5-FU(60μmol·L-1)组、异钩藤碱(130μmol·L-1)+5-FU(60μmol·L-1)组、异钩藤碱(130μmol·L-1)+5-FU(60μmol·L-1)+NSC228155(2μmol·L-1)组。给药处理24 h，对照组不给药。EdU染色、CCK-8检测HepG2或HepG2/5-FU细胞增殖；划痕实验检测HepG2或HepG2/5-FU细胞迁移；Western blotting检测细胞中细胞周期蛋白D1（CyclinD1）、迁移侵袭增强子因子1（MIEN1）、P-糖蛋白（P-gp）、p-EGFR、p-FAK蛋白表达。结果与对照组相比，异钩藤碱低、中、高浓度组EdU阳性率、吸光度(A450)值、划痕愈合率、CyclinD1、MIEN1、p-EGFR、p-FAK蛋白表达显著降低，且呈浓度相关性（PlinD1、 MIEN1、 p-EGFR、 p-FAK蛋白表达显著升高（P<0.05）。与对照组相比，5-FU组HepG2/5-FU细胞EdU阳性率、A450值、划痕愈合率、P-gp、p-EGFR、p-FAK蛋白表达显著降低（P<0.05）；与异钩藤碱组、5-FU组相比，异钩藤碱+5-FU组HepG2/5-FU细胞EdU阳性率、A450值、划痕愈合率、P-gp、p-EGFR、p-FAK蛋白表达降低（P<0.05）；与异钩藤碱+5-FU组相比，异钩藤碱+5-FU+NSC228155组HepG2/5-FU细胞EdU阳性率、A450值、划痕愈合率、P-gp、p-EGFR、p-FAK蛋白显著上调（P<0.05）。结论异钩藤碱抑制HepG2细胞增殖、迁移及降低5-FU耐药性的机制可能与阻断EGFR/FAK通路有关。

关键词：异钩藤碱肝癌表皮生长因子受体/局部黏斑激酶(EGFR/FAK)通路增殖迁移 5-FU耐药性 P-糖蛋白(P-gp)