Most Download
Most Download
-
ArticleHollow Fe4C/FeP Nanoboxes with Heterostructure and Carbon Armor for Efficient and Stable Hydrogen Evolution
Jing-Yi Xie, Hui-Ying Zhao, Yi-Wen Dong, Yang Wu, Da-Peng Liu*, Yong-Ming Chai and Bin Dong*
Chin. J. Struct. Chem. 2022, 41, 2207053-2207058 DOI: 10.14102/j.cnki.0254-5861.2022-0102
July 18, 2022
carbon armor, hollow box, heterostructured electrocatalysts, hydrogen evolution reaction
ABSTRACT
The heterojunction interfacial modulation of FeP is an effective strategy to regulate the intrinsic activity and stability, which is a major challenge to promote the industrial application of FeP-based electrocatalysts. Herein, hollow Fe4C/FeP box with heterojunction interface and carbon armor is successfully synthesized, which can expose numerous active sites and protect catalyst from corrosion. Electrochemical measurements show that Fe4C/FeP exhibits excellent hydrogen evolution activity and stability. It only needs 180 mV to achieve the current density of 10 mA cm-2. The high-activity may be due to the synergistic effects of porous framework, graphitic carbon coating and heterojunction structure of Fe4C and FeP, which optimize the electronic structure and accelerates electron transfer. In addition, the target catalyst can withstand 5000 cycles of CV testing without significant change in properties. The excellent stability may be attributed to the graphitic carbon coating as the armor that can prevent the catalyst from corrosion of electrolyte. This work may provide a synthetic approach to produce a series of carbon-coated and heterojunction structure of transition metal phosphides for water splitting. -
ArticleExplicating the Role of Metal Centers in Porphyrin-Based MOFs of PCN-222(M) for Electrochemical Reduction of CO2
Mengjie Liu, Mengting Peng, Baoxia Dong*, Yunlei Teng, Ligang Feng and Qiang Xu*
Chin. J. Struct. Chem. 2022, 41, 2207046-2207052 DOI: 10.14102/j.cnki.0254-5861.2022-0057
July 18, 2022
PCN-222, electrochemical reduction of CO2, DFT calculation, MOFs
ABSTRACT
The porphyrin-based MOFs formed by combining Zr6 clusters and porphyrin carboxylic acids with clear M-N4 active centers show unique advantages in electrocatalytic reduction of CO2 (CO2RR). However, its conductivity is still the bottleneck that limits its catalytic activity due to the electrical insulation of the Zr cluster. Therefore, the porphyrin-based MOFs of PCN-222(M) (M = Mn, Co, Ni, Zn) with explicit M-N4 coordination were combined with the highly conductive material carbon nanotube (CNT) for discussing the influence of metal centers on the CO2RR performance based on theoretical calculations and experimental observations. The results show that the PCN-222(Mn)/CNT, PCN-222(Co)/CNT, and PCN-222(Zn)/CNT all exhibit high selectivity to CO (FECO > 80%) in the range of -0.60 to -0.70 V vs. RHE. The FECOmax of PCN-222(Mn)/CNT (-0.60 V vs. RHE), PCN-222(Co)/CNT (-0.65 V vs. RHE), and PCN-222(Zn)/CNT (-0.70 V vs. RHE) are 88.5%, 89.3% and 92.5%, respectively. The high catalytic activity of PCN-222(Mn)/CNT and PCN-222(Co)/CNT comes from the excellent electron mobility of their porphyrin rings and their low ΔG*COOH (0.87 and 0.58 eV). It reveals that the strength of backbonding π of the transition metal and its influence on the electron mobility in the porphyrin ring can affect its CO2RR activity. -
ArticleIn-Situ Construction of Sulfur-Doped g-C3N4/defective g-C3N4 Isotype Step-Scheme Heterojunction for Boosting Photocatalytic H2 EvolutionJing Zou, Guodong Liao, Jizhou Jiang*, Zhiguo Xiong, Saishuai Bai, Haitao Wang*, Pingxiu Wu, Peng Zhang and Xin Li*
Chin. J. Struct. Chem. 2022, 41, 2201025-2201033 DOI: 10.14102/j.cnki.0254-5861.2021-0039
January 13, 2022
sulfur-doping, defects, isotype step-scheme heterojunction, g-C3N4, photocatalytic H2
ABSTRACT
The rational construction of a high-efficiency step- scheme heterojunctions is an effective strategy to accelerate the photocatalytic H2. Unfortunately, the variant energy-level matching between two different semiconductor confers limited the photocatalytic performance. Herein, a newfangled graphitic-carbon nitride (g-C3N4) based isotype step-scheme heterojunction, which consists of sulfur-doped and defective active sites in one microstructural unit, is successfully developed by in-situ polymerizing N,N-dimethyl-formamide (DMF) and urea, accompanied by sulfur (S) powder. Therein, the polymerization between the amino groups of DMF and the amide group of urea endows the formation of rich defects. The propulsive integration of S-dopants contributes to the excellent fluffiness and dispersibility of lamellar g-C3N4. Moreover, the developed heterojunction exhibits a significantly enlarged surface area, thus leading to the more exposed catalytically active sites. Most importantly, the simultaneous introduction of S-doping and defects in the units of g-C3N4 also results in a significant improvement in the separation, transfer and recombination efficiency of photo-excited electron-hole pairs. Therefore, the resulting isotype step-scheme heterojunction possesses a superior photocatalytic H2 evolution activity in comparison with pristine g-C3N4. The newly afforded metal-free isotype step-scheme heterojunction in this work will supply a new insight into coupling strategies of heteroatoms doping and defect engineering for various photocatalytic systems. -
ArticleInterfacial Engineering of NiFeP/NiFe-LDH Heterojunction for Efficient Overall Water Splitting
Xuanyu Long, Jiazhi Meng, Jiabao Gu, Lanqing Ling, Qianwen Li, Nan Liu, Kaiwen Wang* and Zequan Li*
Chin. J. Struct. Chem. 2022, 41, 2204046-2204053 DOI: 10.14102/j.cnki.0254-5861.2022-0048
April 8, 2022
overall water splitting, electrocatalysis, heterojunction, phosphide, layered double hydroxide
ABSTRACT
In consideration of application prospect of non-noble metallic materials catalysts, the study of exploring more highly effective electrocatalysts has been focused on by researchers. Herein, a novel strategy is employed to construct a heterojunction consisting of metal phosphide NixFeyP and layered double hydroxide (LDH) with graphene oxide (GO) as conductive support. By adjusting the molar ratio of Ni to Fe, a series of heterojunctions with mixed valence state Feδ+/Fe3+ and Niδ+/Ni2+ (δ is likely close to 0) redox couples are achieved and strong synergistic effects towards overall water splitting performance are found. The optimized catalyst with a Ni/Fe molar ratio of 0.72:0.33, namely Ni0.7Fe0.3P/LDH/GO, delivers ultra-low overpotentials for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) of 79 and 198 mV at the current density of 10 mA·cm-2, respectively. Furthermore, for overall water-splitting practical application, it only requires 1.526 V at 10 mA·cm-2 with robust stability, which is superior to most reported electrocatalysts. Experimental results demonstrate the improved electronic conductivity, enlarged electrochemically active area and accelerated kinetics together account for the enhanced performance. This work supplies new prospects for the promotion and application of such heterojunction electrocatalysts in overall water splitting. -
ArticleUnraveling the Dynamic Structural Evolution of Phthalocyanine Catalysts during CO2 ElectroreductionJianing Mao, Bingbao Mei*, Ji Li, Shuai Yang, Fanfei Sun, Siyu Lu, Wei Chen, Fei Song* and Zheng Jiang*
Chin. J. Struct. Chem. 2022, 41, 2210082-2210088 DOI: 10.14102/j.cnki.0254-5861.2022-0133
October 25, 2022
CO2 electrochemical reduction, HERFD-XAS, model catalysts, difference spectra, structural evolution
ABSTRACT
Understanding the atomic and electronic changes of active sites promotes the whole new sight into electrochemical carbon dioxide reduction reaction (CO2RR), which provides a feasible strategy to achieve carbon neutrality. Here we employ operando high-energy resolution fluorescence-detected X-ray absorption spectroscopy (HERFD-XAS) to track the structural evolution of Ni(II) phthalocyanine (NiPc), considered as the model catalysts with uniform Ni-N4-C8 moiety, during the CO2RR. The HERFD-XAS method is in favor of elucidating the interaction of the reactant/catalyst interface from the atomic electronic structure dimension, facilitating the establishment of the catalytic mechanism and the dynamic structure changes. Based on operando measurement, surface sensitive difference spectra (∆µ) and spectroscopy simulation, the interfacial interactions between the active sites of NiPc and reactants are monitored and the Ni species gradually reduced by increasing the applied potential is discovered. HERFD-XAS method offers an advanced and powerful tool for elucidating the complex catalytic mechanism in further various systems. -
CommunicationStrong High Entropy Alloy-Support Interaction Enables Efficient Electrocatalytic Water Splitting at High Current DensityHongdong Li, Yue Pan, Jianping Lai*, Lei Wang* and Shouhua Feng
Chin. J. Struct. Chem. 2022, 41, 2208003-2208011 DOI: 10.14102/j.cnki.0254-5861.2022-0125
July 25, 2022
high entropy alloy, metal-support interactions, microwave heating, water splitting, activity and durability
ABSTRACT
In electrocatalysis, the stability issue between catalyst and support still needs great attention. Here, a series of high- entropy alloy nanoparticles (HEA-NPs) embedded in carbon cloth (CC) were synthesized by using the scalable strategy-microwave heating. Among them, PtRhCoNiCu/CC exhibits outstanding hydrogen evolution reaction (HER) activity (19 and 170 mV overpotential at 10 and 1000 mA cm-2) and stability (150 h), outperforming other recently reported HEAs catalysts. IrRuCoNiCu/CC displays superior oxygen evolution reaction (OER) activity (166 and 354 mV overpotential at 10 and 1000 mA cm-2) and stability (150 h), and shows a lower overpotential than recently reported HEA catalysts. In water splitting, IrRuCoNiCu/CC(+)//PtRhCoNiCu/CC(-) electrolyzer achieves 500 mA cm-2 (1000 mA cm-2) high current density at 1.76 V (1.88 V) and exhibits excellent stability, which is one of the best catalysts currently. Therefore, the novel supported HEA catalyst with high stability is expected to be a promising candidate material for industrialized water splitting. -
ArticleBoosting Stable and Fast Potassium Storage of Iron Sulfide through Rational Yolk-Shell Design and Ni Doping
Yanmei Gan, Jiajie Zhu, Qixin Zhang, Chaoying Wang, Lunhui Guan and Yi Zhao*
Chin. J. Struct. Chem. 2022, 41, 2205030-2205036 DOI: 10.14102/j.cnki.0254-5861.2022-0044
May 20, 2022
FeS2, Ni-doping, yolk-shell structure, anode, potassium-ion batteries
ABSTRACT
Metal sulfides have been regarded as promising anodes for potassium-ion batteries (PIBs) due to their high theoretical capacities, while the performance is limited by their intrinsic poor conductivity and large volume fluctuation during the insertion/extraction of large potassium ion. Herein, the battery performance of iron sulfide anode is significantly enhanced through yolk-shell (Y-S) structure design and nickel doping, aiming to realize good structure stability and superior electron/ion transportation. For potassium storage, as-prepared Y-S Ni-FeS2@C shows excellent cyclic performance and sustains high capacities of 328 mA h g-1 after 100 cycles at 0.2 A g-1 and 226 mA h g-1 after 1000 cycles at 1 A g-1. Especially, it displays a superior rate capacity of 200 mA h g-1 at 20 A g-1, higher than that of Y-S FeS2@C and most as-reported metal sulfide anodes for PIBs. The experimental analysis and theoretical calculation illuminate the effect of Ni-doping on decreasing the particle size of iron sulfide and enhancing the ion/electron transport ability, thus accounting for the exceptional rate capability of Y-S Ni-FeS2@C composite. -
ArticleVersatile Inorganic Oligomer-Based Photochromic Spiropyrane GelsJiajia Song, Wei Duan, Yun Chen* and Xiangyang Liu*
Chin. J. Struct. Chem. 2022, 41, 2205037-2205047 DOI: 10.14102/j.cnki.0254-5861.2022-0061
May 20, 2022
inorganic oligomer, photochromic, gels, naked-eye detection of hydrazine
ABSTRACT
Here we report an example of a general strategy for the immobilization of various different photochromic spiropyran molecules on eco-friendly cheap nanomatrix. The spiropyrans are encapsulated in calcium salt oligomers-based gels by centrifugation, forming an inorganic oligomer-based gelatinous photoswitchable hybrid material. Ca2+ is also used to regulate the optical properties of spiropyrans through chelation. The oligomer-based gel can not only provide the space required for photoisomerization, but also reduce the interference of the surrounding environment on the photochromic properties. Moreover, a practical paper-based and colloidal flexible substrate platform is constructed for the removal and naked-eye detection of liquid and gaseous hydrazine at room temperature based on the reactivity of the formyl group on spiropyrans loaded in Ca3(PO4)2 oligomers. This general strategy can be used for other inorganic oligomer-based molecular switches and sensing systems. -
ArticleCoordination Assembly of Tetrahedral Ti4(embonate)6 Cages with Alkaline-Earth Metal IonsRuiyan Chen, Guanghui Chen, Yanping He* and Jian Zhang*
Chin. J. Struct. Chem. 2022, 41, 2201001-2201006 DOI: 10.14102/j.cnki.0254-5861.2021-0016
January 13, 2022
metal-organic cages, stepwise-assembly, alkaline-earth, structures, nonlinear optics
ABSTRACT
Recently, the tetrahedral Ti4L6 cage (L = embonate) has been applied as the starting material to realize coordination assembly with transition and rare-earth ornoble metal ions through a two-step reaction. In this work, by employing the Ti4L6 cages to assemble with alkaline-earth metal ions (such as Mg2+, Ca2+ and Ba2+) under different solvothermal conditions, a series of Ti4L6-based structures from simple cages to 1D chain, 2D layer and 3D framework have been synthesized and structurally characterized. In addition, thermal stability, phase purity, UV-vis absorption spectrum, the fluorescent and third-order nonlinear-optical properties are also investigated.
-
ArticleP-Ni4Mo Catalyst for Seawater Electrolysis with High Current Density and Durability
Gai Li, Suyang Feng, Jing Li*, Peilin Deng, Xinlong Tian, Chongtai Wang and Yingjie Hua*
Chin. J. Struct. Chem. 2022, 41, 2207068-2207073 DOI: 10.14102/j.cnki.0254-5861.2022-0110
July 18, 2022
seawater electrolysis, electrodeposition, hydrogen evolution reaction, phosphorus doping
ABSTRACT
Rational design of highly efficient and durable electrocatalysts with low cost to replace noble-metal based catalysts for seawater electrolysis is extremely desirable, but challenging. In this work, we demonstrate a rapid electrodeposition method by growing P-Ni4Mo on the surface of the copper foam (CF) substrate to synthesize an efficient seawater electrolysis catalyst (P-Ni4Mo/CF). The catalyst exhibited considerable HER performance and stability in alkaline seawater, with the overpotential as low as 260 mV at a current density of 100 mA cm-2. The P-Ni4Mo/CF is capable of achieving 1.0 A cm-2 with an overpotential of 551 mV, which is slightly worse than that of the Pt/C catalyst (453 mV). Moreover, P-Ni4Mo/CF demonstrates robust durability, with almost no activity loss after the durability test for more than 200 h. This work not only reports a new catalyst for seawater electrolysis, but also presents a strategy for the performance enhancement of seawater electrolysis. -
ArticleNi3N Modified MOF Heterostructure with Tailored Electronic Structure for Efficient Overall Water SplittingHongnan Jia, Na Yao, Juan Zhu, Yujia Liu, Yunhao Lao, Hengjiang Cong* and Wei Luo*
Chin. J. Struct. Chem. 2022, 41, 2208031-2208036 DOI: 10.14102/j.cnki.0254-5861.2022-0112
July 25, 2022
hydrogen evolution reaction, Ni3N, MOF, DFT calculation, water splitting
ABSTRACT
Exploring bifunctional electrocatalysts with high-efficiency and stability toward overall water splitting is desirable for sustainable energy technologies, yet challenging. Herein, we report the construction of Ni3N on the surface of Ni-MOF-74 through an in-situ nitriding process. The obtained Ni-MOF-74/Ni3N exhibits remarkable HER activity, with an overpotential of 73 mV to deliver 10 mA cm−2. Theoretical calculations and experimental study demonstrate the electron transport between Ni3N and Ni-MOF-74, leading to the improved H2O adsorption, optimized hydrogen adsorption, and increased Had diffusion, which contributes to the enhanced HER performance. Besides, the obtained Ni-MOF-74/Ni3N also possesses outstanding activity toward OER and overall water splitting. -
Morphology Engineering toward Highly Emissive Mn2+ Doped PEA2PbBr4 Perovskite with Their LED Application via Phosphonium PassivationYu-Feng Sang, Liang-Jin Xu* and Zhong-Ning Chen*
Chin. J. Struct. Chem. 2022, 41, 2205070-2205076 DOI: 10.14102/j.cnki.0254-5861.2022-0088
May 20, 2022
2D perovskite, Mn2+ doped, energy transfer, perovskite LED
ABSTRACT
Mn2+-doped lead halide perovskites either in 3D or 2D have been extensively explored due to their rich energy-transfer behaviors. While their application on LED is still lagging behind in comparison to non-doped 3D perovskite due to inferior film-formation and low luminescent efficiency. Here we report an in-situ-formed Mn2+ doped 2D perovskite nanocrystal (NCs) film by introducing quaternary phosphonium salt during the crystallizing process. The as-formed film shows improved luminescent efficiency with emission peaked at 600 nm and photoluminescence quantum yield (PLQY) of as high as 73.37%, which is about 1.3 times higher than that of pristine film. Further characterizations confirm the enhanced confinement effect from smaller size particle is responsible for the improved luminescent efficiency. The perovskite LEDs based on pristine and phosphonium passivated thin films were fabricated, and a great improvement in the external quantum efficiency of these LEDs (from 0.0017% to 0.12%) is observed due to the improved morphology and enhanced luminescent efficiency. -
ArticleAtomically Thin 2D TiO2 Nanosheets with Ligand Modified Surface for Ultra-Sensitive Humidity SensorJianze Xiao, Zhihua Fu, Guane Wang, Xiaoliang Ye* and Gang Xu*
Chin. J. Struct. Chem. 2022, 41, 2204054-2204060 DOI: 10.14102/j.cnki.0254-5861.2022-0046
April 8, 2022
TiO2 nanosheet, ligand modification, ultra-sensitive, chemiresistive, humidity sensing
ABSTRACT
As a kind of two-dimensional (2D) nanostructured materials, metal oxide nanosheets (MONS) are attractive and promising humidity sensing materials due to their considerable surface area, good charge carrier transportation, and designable surface functional groups properties. Nevertheless, the ultra-thin MONS modified with active functional groups for humidity sensing are still rare. As a proof of concept, the atomically thin TiO2 nanosheets with high surface area and electron-donating amino groups are prepared by a structure-maintained post-ligand modification strategy. The fabricated TiO2-based sensors demonstrate superior humidity sensing performance with high response, short response time, narrow hysteresis, and ultra-low theoretical limit of detection of about 15 ppm. Additionally, the possible mechanism is proposed from the AC complex impedance measurements and DC instantaneous reverse polarity experiments. This work provides a possible path for developing the high-performance 2D nanostructured metal oxides-based humidity materials through the surface chemical method. -
ArticleIn-situ Synthesis of CQDs/BiOBr Material via Mechanical Ball Milling with Enhanced Photocatalytic PerformancesXingwang Yan, Bin Wang, Mengxia Ji, Qi Jiang, Gaopeng Liu, Pengjun Liu*, Sheng Yin, Huaming Li and Jiexiang Xia*
Chin. J. Struct. Chem. 2022, 41, 2208044-2208051 DOI: 10.14102/j.cnki.0254-5861.2022-0141
July 25, 2022
CQDs, BiOBr, photocatalysis, pollutant degradation
ABSTRACT
Designing simple, efficient, and environmentally friendly methods to construct high-efficient photocatalysts is an important strategy to promote the further development of the field of photocatalysis. Herein, flower-like carbon quantum dots (CQDs)/BiOBr composite photocatalysts have been prepared via in-situ synthesis by mechanical ball milling in the existence of ionic liquid. The CQDs/BiOBr composites exhibit higher photo-degradation performance for tetracycline (TC) than BiOBr monomer and the commercial Bi2O3 under visible light irradiation. For comparison, the different Br sources and synthetic methods are chosen to prepare BiOBr and CQDs/BiOBr composites. Photocatalysts prepared by ball milling and ionic liquid present significantly enhanced photocatalytic performance for removing TC. In addition, the introduction of CQDs could distinctly enhance the photocatalytic performances of pure BiOBr. The reason is that CQDs as electron acceptor effectively separate electrons and holes and inhibit their recombination. The intermediates during photocatalytic degradation were tested using liquid chromatography-mass spectrometry (LC-MS) and possible degradation pathways were given. During degradation, •OH, O2•- and h+ were identified to be the main active species based on electron spin resonance (ESR) spectra and free radical trapping experiments. A possible mechanism of CQDs/BiOBr with enhanced photocatalytic performances was further proposed.
-
ArticleTwo Bisligand-Coordinated Luminescent Zn(II)-Coordination Polymers for Sensing of Ions and Pesticides in Aqueous Solutions
Zhao-Di Zhou, Zi-Long Xu, Dan Wang, Lin-Fang Jia, Han-Qing Zhao, Bao-Yi Yu* and Chong-Chen Wang*
Chin. J. Struct. Chem. 2022, 41, 2209087-2209093 DOI: 10.14102/j.cnki.0254-5861.2022-0077
September 22, 2022
coordination polymer, fluorescence sensing, heavy metal ions, pesticides, X-ray crystallography
ABSTRACT
Two coordination polymers (CPs) [Zn(PTA)(DTP)(H2O)2]·(DMF) (CP-1) and [Zn(BTC)(DTP)]·(CH3CN)1.5·(H2O)4 (CP-2) with one- and two-dimensional architectures were synthesized from Zn(II) ion and different organic linkers like terephthalic acid (H2PTA), benzene-1,3,5-tricarboxylic acid (H3BTC), and 3,5-di(1,2,4-triazol-1-yl) pyridine (DTP). The fluorescent sensing experiments showed that the two CPs displayed effective, sensitive, and selective abilities towards Fe3+ and Cr2O72-. For sensing the pesticides, CP-1 outperforms in sensing of metamitron (MMT) and CP-2 is ultrasensitive towards imidacloprid (IMI). The possible mechanisms involved in the quenching of the fluorescence intensity include the inner filter effect (IFE) and the fluore- scence resonance energy transfer (FRET) effect. -
ArticleCo-Construction of Sulfur Vacancies and Heterogeneous Interface into Ni3S2/MoS2 Catalysts to Achieve Highly Efficient Overall Water SplittingZhaoyang An, Hui Xue*, Jing Sun, Niankun Guo, Tianshan Song, Jiawen Sun, Yi-Ru Hao and Qin Wang*
Chin. J. Struct. Chem. 2022, 41, 2208037-2208043 DOI: 10.14102/j.cnki.0254-5861.2022-0130
July 25, 2022
sulfur vacancies, heterostructures, transition metal chalcogenides, overall water splitting
ABSTRACT
Integrating the advantages of anion vacancies and heterostructures into the catalytic materials may increase the binding affinities to intermediates, provide more active sites, and significantly promote the activity of overall water splitting. However, the successful assembly of anion vacancies and heterostructures for high-efficiency water splitting performance is still challenging. In this work, we ingeniously present the co-construction of sulfur vacancies and heterogeneous interface into Ni3S2/MoS2 catalysts on nickel foam (NF). The introduction of sulfur vacancies and Ni3S2/MoS2 heterostructures can significantly improve electron and ion transport, effectively improve structural stability, and enhance overall water splitting activity. The obtained VS-Ni3S2/MoS2 catalysts (VS stands for sulfur vacancies) exhibit superior OER and HER activities, and the overpotentials for OER and HER are 180 and 71 mV at 10 mA·cm-2, respectively. Furthermore, a low water splitting voltage of 1.46 V is required at 10 mA·cm-2 for the VS-Ni3S2/MoS2 catalysts, which is considerably lower than most of the water splitting electrocatalysts currently reported. This work offers an effective mean for the preparation of catalysts with both anion vacancies and heterostructures for achieving high-performance alkaline overall water splitting. -
LetterCyano and Isocyano-substituted Tetraphenylethylene with AIE Behavior and Mechanoresponsive BehaviorQing Liu, Shusheng Yue, Zhangqiang Yan, Yongfa Xie* and Hu Cai*
Chin. J. Struct. Chem. 2022, 41, 2204075-2204082 DOI: 10.14102/j.cnki.0254-5861.2021-0049
April 8, 2022
cyano-group, isocyano-group, tetraphenylethlene (TPE), aggregation induced emission (AIE), mechanochromic
ABSTRACT
Dual-functional materials with AIE behavior and mechanoresponsive behavior have attracted considerable attention due to their promising applications in mechano-sensors, optical storage, solid-state optoelectric devices and bioimage systems. AIEgens bearing tetraphenylethylene (TPE) core become elementary building blocks in many fluorescent functional materials. In this article, cyano and isocyano-electronic withdrawing groups are incorporated with TPE skeleton to form tetracyanophenylethylene (TPE-CN) and tetraisocyanophenylethylene (TPE-NC). Their structures are confirmed by NMR, Mass Spectra and single crystal X-ray measurement. These two isomers reflect aggregation-induced emission (AIE) property in solution state and mechanochromic behavior in solid state. Interestingly, their luminescent intensities, quantum yields and fluorescent lifetime in solid state have an obvious increase upon grinding. The theoretical calculation of these two compounds clarify their difference in optical properties. The mechanochromic mechanism is also intensively explained by powder X-ray measurements. -
ArticleContributions of Cs and Rb on Inhibiting Photo-induced Phase Segregation and Enhancement Optoelectronic Performances of MA1-yXyPbI1.8Br1.2(X = Cs, Rb) Single Crystals
Qing Yao, Kaiyu Wang, Jie Zhang, Changqian Li, Chenyu Shang, Feitong Chen, Qi Huang, Qiqi Zhao, Weiwei Zhang, Xiaoyuan Zhan and Jianxu Ding*
Chin. J. Struct. Chem. 2022, 41, 2205077-2205084 DOI: 10.14102/j.cnki.0254-5861.2022-0089
May 20, 2022
perovskite single crystal, photo-induced phase segregation, mixed A-cation, optoelectronic performances
ABSTRACT
Introducing inorganic cation into hybrid organic-inorganic perovskites (HOIPs) has attracted great attention because of the enhancement stabilities without sacrificing their excellent optoelectronic properties. Here, we introduce Cs and Rb into MAPbI1.8Br1.2 single crystals (SCs) to dig out the mixed cation effect on optoelectronic performances and phase stabilities. Both Rb and Cs can increase the lattice capacity, which is sufficient to relieve the lattice stress caused by photon energy, thus achieving the purpose of stabilizing the lattice structure and inhibiting migration of halide ions, compared with MAPbI1.8Br1.2 SC. On the other hand, the smaller polarity of Rb and Cs reduces the electron-phonon coupling, thus significantly inhibiting the migration of halide ions. Meanwhile, through planar photo-detectors, MA0.9Cs0.1PbI1.8Br1.2-based device behaves much excellent optoelectronic performance (R = 0.170 A/W, EQE = 51.39 %, D*= 4.42 × 1012Jones, on/off ratio: ~522). -
ArticleHighly Efficient Photocatalytic CO2 Methanation over Ru-Doped TiO2 with Tunable Oxygen Vacancies
Zheyue Li†, Di Wu†, Wanbing Gong*, Jiayi Li, Shuaikang Sang, Hengjie Liu, Ran Long and Yujie Xiong*
Chin. J. Struct. Chem. 2022, 41, 2212043-2212050 DOI: 10.14102/j.cnki.0254-5861.2022-0212
December 2, 2022
photocatalysis, CO2 methanation, metal doping, titanium oxide, oxygen vacancies
ABSTRACT
Solar-driven CO2 methanation is an imperative and promising approach to relieve the global warming and environmental crisis, yet remains a great challenge due to the low reaction efficiency, unsatisfactory selectivity and poor stability. In this work, we demonstrate a facile and efficient strategy to prepare Ru-doped TiO2 photocatalyst with tunable oxygen vacancies using the ascorbic acid as a reducing agent for the CO2 methanation reaction. The optimal Ru-TiO2-OV-50 exhibits a remarkable CH4 production rate of 81.7 mmol g-1 h-1 with a 100% CH4 selectivity under a 1.5 W cm-2 light illumination, which is significantly higher than commercial Ru/TiO2 and other reported catalysts. We reveal that the superior photocatalytic CO2 methanation performance is mainly due to the synergistic effect of Ru doping and TiO2 with tunable oxygen vacancies. Impressively, the light rather than thermal effect is confirmed as the main influencing factor by experimental studies. In addition, in situ spectroscopic technology is performed to investigate the CO2 methanation reaction pathway. This work will open an avenue to design and prepare highly efficient photocatalyst with tunable oxygen vacancies for CO2 conversion and other related applications. -
ArticlePyrene-Benzothiadiazole-Based Polymer/CdS 2D/2D Organic/Inorganic Hybrid S-scheme Heterojunction for Efficient Photocatalytic H2 Evolution
Ruiqi Gao, Huan He, Junxian Bai, Lei Hao, Rongchen Shen*, Peng Zhang, Youji Li and Xin Li*
Chin. J. Struct. Chem. 2022, 41, 2206031-2206038 DOI: 10.14102/j.cnki.0254-5861.2022-0096
June 20, 2022
photocatalytic hydrogen evolution, pyrene-benzothiadiazole-based conjugated polymers, S-scheme heterojunction, CdS
ABSTRACT
Nowadays, conjugated polymers have garnered numerous attention as a new class of organic photocatalysts due to their tunable electronic properties, low cost, excellent stability and sufficient light-absorption performance. In particular, pyrene-benzothiadiazole-based conjugated polymer (PBBP) has been considered to be a new type of conjugated polymers for photocatalytic H2 evolution. However, the poor charge separation seriously limits its practical application in H2 evolution. In this work, a PBBP-based polymer/CdS 2D/2D organic/inorganic S-scheme heterojunction photocatalyst with a strong internal electric field is, for the first time, prepared for efficient photocatalytic hydrogen evolution. The pyrene-benzothiadiazole-based conjugated polymers (PBBP) are synthesized by the Suzuki-Miyaura reactions. Then, the hybrid heterojunction photocatalysts are fabricated by coupling CdS with it through the ultrasonic mixing method. As a result, the highest H2-production rate of 15.83 mmol h-1 g-1 is achieved on 20% PBBP/CdS composite under visible-light irradiation, nearly 2.7 times higher than that of pure CdS. The apparent quantum efficiency (AQE) of 20% PBBP/CdS composite could reach 8.66% at λ = 420 nm. The enhanced activity could be attributed to the construction of S-scheme heterojunction, which accelerates the recombination of carriers with weaker redox ability and maintains the strong reducibility of electrons in CdS. This work provides a protocol for pyrene-benzothiadiazole-based conjugated polymers to prepare S-scheme heterojunction photocatalysts based on organic/inorganic coupling.
- Address: Fuzhou High & New Technology Industrial Zone, Shangjie, Minhou, Fuzhou, Fujian 350108, China
- Tel: (86)-591-63173769, 63173770
- E-mail: cjsc@fjirsm.ac.cn