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B-n covalent bond-involved π-extension of multiple resonance emitters enables high-performance narrowband electroluminescence

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national Science review 2024年第06期11卷 243-253页

作者： Xingyu Huang Jiahui Liu Yulin Xu Guohao Chen Manli Huang Mingxin Yu Xialei Lv Xiaojun Yin yang Zou Jingsheng Miao Xiaosong Cao Chuluo yang Shenzhen Key Laboratory of new Information Display and Storage Materials College of Materials Science and EngineeringShenzhen University College of Physics and Optoelectr.nic Engineer.ng Shenzhen University

Multi-bor.n-embedded multiple resonance thermally activated delayed fluorescence（Mr-TADF） emitters show promise for achieving both high color-purity emission and high exciton utilization ***, their development is often impeded by a limited synthetic scope and excessive molecular weights,which challenge material acquisition and organic light-emitting diode（OLED） fabrication by vacuum deposition. Herein, we put forward a B–n covalent bond-involved π-extension strategy via post-functionalization of Mr frameworks, leading to the generation of high-order B/n-based motifs. The structurally and electr.nically extended π-system not only enhances molecular rigidity to narrow emission linewidth but also promotes reverse intersystem crossing to mitigate efficiency roll-off. As illustrated examples, ultra-narrowband sky-blue emitters（full-width at half-maximum as small as 8 nm in n-hexane）have been developed with multi-dimensional improvement in photophysical properties compared to their precursor emitters, which enables narrowband OLEDs with external quantum efficiencies(EQEmax) of up to 42.6%, in company with alleviated efficiency decline at high brightness, representing the best efficiency reported for single-host OLEDs. The success of these emitters highlights the effectiveness of our molecular design strategy for advanced Mr-TADF emitters and confirms their extensive potential in high-performance optoelectr.nic devices.

关键词： narrowband electroluminescence thermally activated delayed fluorescence (TADF) multiple resonance emitters ultra-high external quantum efficiency

Engineer.ng ru（n^n）3-modified covalent organic framework for photocatalytic olefin epoxidation

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Science China Chemistry 2024年第11期67卷 3719-3728页

作者： Yan-Lin Li Sheng-Li Huang Guo-Yu yang Key Laboratory of Cluster Science (Ministry of Education) Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion MaterialsSchool of Chemistry and Chemical Engineering Beijing Institute of Technology

Photocatalytic olefin oxidation using air as an oxidant is an envir.nmentally friendly method for producing epoxides. Covalent organic frameworks（COFs） have emerged as promising photocatalysts in various organic synthesis reactions. The combination of tri-（2-pyridinal aldehyde）-containing precursor with 4,4’,4’’-（1,3,5-triazine-2,4,6-triyl）trianiline generated（n^n）-I-COF. Via imine-to-quinoline tr.nsformation and coordination anchorage of ru（n^n）3unit, ru（n^n）3@Q-COF was obtained with improved chemical stability, skeleton conjugation, and novel photochemical characteristics, and demonstrated excellent photocatalytic activity in olefin epoxidation with a wide r.nge of substrates. The presence of H2O played a crucial role in the formation of reactive oxygen species（rOSs）, which in turn influenced the olefin oxidation process. The hydrophilicity of ru（n^n）3facilitated the approach of H2O and O2to the photogenerated charges, thereby promoting rOSs generation. The lipophilicity of Q-COF allowed for the absorption of olefin substrates, and its nano-channels increased encounter.ng possibility between olefins and rOSs. Consequently, ru（n^n）3@Q-COF provided an intriguing platform for olefin photooxidation and could be recycled multiple times without any degradation in performance. This report revealed that the conversion of classical rOSs into less potent oxidants with rapid kinetic rates played a crucial role in achieving highly efficient and selective epoxidation of terminal olefins.

关键词： polypyridyl ru covalent organic framework olefin epoxidation photocatalysis

Langmuir-Schaefer Film Investigation and Density Functional Theory Band Gap Calculations of Calix[n]ar.ne-Para-Aminobenzoic Acid for Drug nanosensor Application

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Journal of Wuhan University of Technology(Materials Science) 2024年第5期39卷 1311-1318页

作者： WOnG Yeong Yi F L Supian A radzwan M Musa n F n Abd Karim Department of Physics Sultan Idris Education UniversityTanjong Malim 35900Malaysia Department of Chemistry Sultan Idris Education UniversityTanjong Malim 35900Malaysia

Calix[n]ar.nes was utilized to detect PABA,the primary sunscreen *** study investigates the interaction of calix[4]ar.ne(C4),calix[6]ar.ne(C6),and PABA using the Langmuir method and first-pr.nciple density functional theory(DFT).Using the Langmuir-Schaefer(LS)technique,an ultrathin film composed of calix[n]ar.nes and their complexes with PABA was deposited on various *** on the Langmuir study,the PABA molecule was bonded to the lower rims of both C4 and C6 with the host-guest ratio of 1:*** of the LS films formed were then characterized by ultravioletvisible spectroscopy(UV-Vis),Fourier-tr.nsform infrared spectroscopy(FTIr)and carbon,hydrogen,nitrogen,sulfur elemental analyzer(CHnS).The band gap reduction obtained in the DFT study denotes the charge tr.nsfer interaction with promising reactivity between the calix[n]ar.nes and *** sensing of PABA by C4 and C6 is successful based on the formation of bonding between them due to the hosts’effective trapping *** outcomes of this study could be applied to drug delivery systems for future pharmaceutical and medical applications.

关键词： calix[n]ar.nes band gap density functional theory Langmuir-Schaefer PABA sensor

Coordinated responses of leaf and nodule traits contribute to the accumulation of n in relay intercropped soybean

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Journal of Integrative Agriculture 2024年第6期23卷 1910-1928页

作者： Ping Chen Qing Du Benchuan Zheng Huan yang Zhidan Fu Kai Luo Ping Lin Yilin Li Tian Pu Taiwen Yong Wenyu yang College of Agr.nomy Sichuan Agricultural University/Sichuan Engineering Research Center for Crop Strip Intercropping System/Key Laboratory of Crop Ecophysiology and Farming System in SouthwestMinistry of Agriculture and Rural AffairsChengdu 611130China Crop research Institute Sichuan Academy of Agricultural SciencesChengdu 610066China

Maize(Zea mays L.)-soybean(Glycine max ***.)relay intercropping provides a way to enhance land ***,the late-planted soybean suffers from shading by the *** maize harvest,how the recovery growth influences the leaf and nodule traits remains unclear.A three-year field experiment was conducted to evaluate the effects of genotypes,i.e.,supernodulating(nts1007),nandou 12(nD12),and Guixia 3(GX3),and crop configurations,i.e.,the interspecific row spacing of 45(I45),60(I60),75 cm(I75),and sole soybean(SS),on soybean recovery growth and n *** results showed that intercropping reduced the soybean total leaf area(LA)by reducing both the leaf number(Ln)and unit leaflet area(LUA),and it reduced the nodule dry weight(nW)by reducing both the nodule number.nn)and nodule diameter.nD)compared with the *** correlation and pr.ncipal component analysis(PCA)indicated a co-variability of the leaf and nodule traits in response to the genotype and crop configuration *** the recovery growth stages,the compensatory growth promoted soybean growth to reduce the gaps of leaf and nodule traits between intercropping and *** relative growth rates of ureide(rGr_U)and nitrogen(rGr.n)accumulation were higher in intercropping than in *** achieved more significant sucrose and starch contents compared with ***12 and GX3 showed more robust compensatory growth than nts1007 in *** the recovery growth of relay intercropping soybean improved biomass and nitrogen accumulation,nD12 gained a more significant partial land equivalent ratio(pLEr)than *** I60 treatment achieved more robust compensation effects on biomass and n accumulation than the other ***,I60 showed a higher.nodule sucrose content and greater shoot ureide and n accumulation than ***,intercropping nD12 with maize using an interspecific row spacing of 60 cm was optimal for both yield advantage and n accumulation.

关键词： relay intercropping genotype crop configuration symbiotic nitrogen fixation soybean nodule

Modulation of charge in C_(9)n_(4) monolayer for a highcapacity hydrogen storage as a switchable strategy

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Fr.ntiers of physics 2024年第4期19卷 47-55页

作者： Lin Ju Junxian Liu Minghui Wang Shenbo yang Shuli Liu School of Physics and Electric Engineer.ng Anyang Normal UniversityAnyang 455000China School of Mechanical Medical and Process EngineeringQueensland University of TechnologyBrisbane QLD 4001Australia Hongzhiwei Technology(Shanghai)Co.Ltd. 1599 Xinjinqiao RoadPudongShanghai 201206China

Developing advanced hydrogen storage materials with high capacity and efficient reversibility is a crucial aspect for utilizing hydrogen source as a promising alternate to fossil *** this paper,we have systematically investigated the hydrogen storage properties of neutral and negatively charged C_(9)n_(4) monolayer based on density functional theory(DFT).Our foundings indicate that injecting additional electr.ns into the adsorbent significantly boosts the adsorption capacity of C_(9)n_(4) monolayer to H2 *** gravimetric density of negatively charged C_(9)n_(4) monolayer can reach up to 10.80 wt% when fully covered with *** other hydrogen storage methods,the storage and release processes happen automatically upon introducing or removing extra ***,these operations can be easily adjusted through activating or deactivating the charging *** a result,the method is easily reversible and has tunable kinetics without requir.ng particular ***,C_(9)n_(4) is proved to be a suitable candidate for efficient electr.n injection/release due to its well electrical *** work can serve as a valuable guide in the quest for a novel category of materials for hydrogen storage with high capacity.

关键词： hydrogen storage C_(9)n_(4)monolayer charge modulation density functional theory

Soil type and wetting intensity control the enhancement extent of n_(2)O efflux in soil with drought and rewetting cycles

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International Soil and Water Conservation research 2024年第1期12卷 137-144页

作者： Panpan Jiao Lei yang Zhongwu Li Peng Zheng Xiaodong nie School of Geographical Sciences Hunan Normal UniversityChangsha 410081China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau The Research Center of Soil and Water Conservation and Ecological EnvironmentChinese Academy of Sciences and Ministry of EducationYangling 712100China Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water ResourcesYangling 712100China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Soil Envir.nment and Pollution remediation Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China

Climate change alters the intensity and frequency of drought and rewetting(D/W)events;however,the influence patterns of D/W on soil n_(2)O efflux in the water-limited area were not fully ***,the impacts of D/W cycles varying in differ.nt extent of rewetting and frequency to n_(2)O efflux in two kinds of soil on the Loess Plateau were *** incubation conditions consisted of 1)D/W treatments with four 7-day cycles from 10%water holding capacity(WHC)to 60%WHC or 90%WHC,2)constant moisture of 60%WHC and 90%*** pulse of n_(2)O efflux rate under 10-60%WHC treatment was higher than that under 10-90%WHC treatment in calcic cambisols,while opposite tr.nd was observed in earth-cumuli-orthic ***,the pulse of n_(2)O efflux rate decreased as cycle number increased for differ.nt wetting intensities and soil *** direct n_(2)O efflux under 10-60%WHC and 10-90%WHC treatments were 5.49 and 1.89μg n_(2)O-n g^(-1)soil in calcic cambisols,with those being 1.92 and 10.85μg n_(2)O-n g^(-1)soil in earth-cumuli-orthic anthrosols,*** n loss in earth-cumuli-orthic anthrosols was approximately 5.74 times greater than that in calcic cambisols under 10-90%WHC treatment,whereas the n loss under 10-60%WHC treatment was about 2.86 times greater in calcic cambisols than that in earth-cumuli-orthic *** study suggested that extreme rainfall events can enhance the n_(2)O efflux and n loss in agricultural soils on the Loess Plateau in terms of soil type and wetting intensity,which should not be ignored in the n fertilizer management.

关键词： Drought/rewetting cycles n_(2)O efflux Wetting intensity Microbial biomass n Dissolved organic n Loess plateau

Polyelectrolyte Complexes between Hyperbr.nched and Linear Polysaccharides: Fucoidan/Chitosan

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Chinese Journal of Polymer Science 2024年第4期42卷 468-479页

作者： Ekater.na r.Gasilova Daria n.Poshina Aleksandra O.Sitnikova natalia n.Saprykina Yury A.Skorik Institute of Macromolecular Compounds of the russian Academy of Sciences Bolshoi VO 31St.Petersburg199004Russian Federation

Polyelectrolyte complexes(PECs)of hyperbr.nched(HB)and linear polysaccharides are promising as more effective encapsulation agents compared to PECs formed by linear *** investigated the PECs between the HB anionic polysaccharide fucoidan(FUC)and the cationic linear polysaccharide chitosan(CS).The FUC had a molecular weight(MW)of 30×*** PECs were prepared in three solvents(water,0.01 and 0.1 mol/L acetic acid)with CS of MW of 15,110 and 170 kDa,and deacetylation degrees(DDA)of 70%and 97%.The structures of the PECs and the initial FUC were investigated by multi-angle static and dynamic light *** the FUC contained 18 wt%of—OSO3 groups and 5 wt%of ur.nic acid units,it was a“str.ng-weak”copolyanion,so the HB macromolecules of the FUC formed nanogel particles in 0.1 mol/L AcOH and open br.nched structures in water,as confirmed by the Kratky *** mixing the solutions of original components,the PEC structures underwent an equilibration period,the duration of which increased with the MW of *** the charge stoichiometry was approached,the PECs shr.nk;the fractal dimension approached unity,indicating the side-by-side packing of adjacent FUC br.nches with the help of *** aggregation in the vicinity of the charge compensation was hardly observed,as it occurred in a very narrow *** PEC content at theζ-potential inversion depended on solvents’pH and the DDA of *** the extreme case of core-shell PECs in 0.1 mol/L AcOH,obtained by mixing FUC nanogels with the solutions of high MW CS of 97%DDA,the protruding tails of CS formed a positively charged shell in the whole r.nge of FUC content(10 wt%nning electr.n microscopy and atomic force microscopy images of dried samples were discussed in relation to the light scatter.ng results.

关键词： Polyelectrolyte complexes Chitosan Hyperbr.nched fucoidan Light scatter.ng

Highly Sensitive Ammonia Gas Sensors at room Temperature Based on the Catalytic Mechanism of n,C Coordinated ni Single-Atom Active Center

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nano-Micro Letters 2024年第12期16卷 515-531页

作者： Wenjing Quan Jia Shi Min Zeng Wen Lv Xiyu Chen Chao Fan Yongwei Zhang Zhou Liu Xiaolu Huang Jianhua yang nantao Hu Tao Wang Zhi yang national Key Laboratory of Advanced Micro and nano Manufacture Technology Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Department of Micro/nano Electr.nics School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Shanghai Key Laboratory of Intelligent Sensing and Detection Technology School of Mechanical and Power EngineeringEast China University of Science and TechnologyShanghai 200237People’s Republic of China

Significant challenges are posed by the limitations of gas sensing mechanisms for trace-level detection of ammonia(nH3).In this study,we propose to exploit single-atom catalytic activation and targeted adsorption properties to achieve highly sensitive and selective nH3 gas ***,ni singleatom active sites based on n,C coordination(ni-n-C)were interfacially confined on the surface of two-dimensional(2D)MXene nanosheets(ni-n-C/Ti_(3)C_(2)Tx),and a fully flexible gas sensor(MnPE-ni-n-C/Ti_(3)C_(2)Tx)was *** sensor demonstrates a remarkable response value to 5 ppm nH3(27.3%),excellent selectivity for.nH3,and a low theoretical detection limit of 12.1 *** analysis by density functional calculation reveals that the ni single-atom center with n,C coordination exhibits specific targeted adsorption properties for ***,its catalytic activation effect effectively reduces the Gibbs free energy of the sensing elemental reaction,while its electr.nic structure promotes the spill-over effect of reactive oxygen species at the gas-solid *** sensor has a dual-channel sensing mechanism of both chemical and electr.nic sensitization,which facilitates efficient electr.n tr.nsfer to the 2D MXene conductive network,resulting in the formation of the nH3 gas molecule sensing ***,the passivation of MXene edge defects by a conjugated hydrogen bond network enhances the long-term stability of MXene-based electrodes under high humidity *** work achieves highly sensitive room-temperature nH3 gas detection based on the catalytic mechanism of ni single-atom active center with n,C coordination,which provides a novel gas sensing mechanism for room-temperature trace gas detection research.

关键词： Gas sensor Single atom Catalytic activation Targeted adsorption End-sealing passivation

Polyoxometalates-derived ternary metal oxides electrocatalyst for.n_(2) reduction under ambient conditions

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Tungsten 2024年第2期6卷 428-437页

作者： Meng-Le yang Zhong-Xin Jin Xi-Xian Cao Xin-Ming Wang Hui-Yuan Ma Hai-Jun Pang Gui-Xin yang The School of Material Science and Chemical Engineer.ng Harbin University of Science and TechnologyHarbin 150040China

Accelerating the breaking of the nitrogen nonpolar bond(n≡n)is an important factor to improve the effi ciency of the electro-catalytic nitrogen reduction reaction(e-nrr).In this work,polyoxometalates-derived FeMo-based ternary oxide materials MoO_(2)-Mo_(4)O_(11)-FeMoO_(4)@X(abbreviated as MoFeO@X,X represents the synthesis temperature of 650,750 and 850℃)were designed and synthesized for e-nrr under ambient *** scanning electr.n microscopy images of MoFeO@750 show an ellipsoidal-like structure(0.86×0.6μm).The relatively large specifi c surface area,formation of multiple interfaces,together with the synergistic eff ect of ir.n and molybdenum bimetals,would make MoFeO@X catalyst more easily absorb and activate n_(2)in the ***,the synthesized MoFeO@750 shows an optimal nH_(3)production rate of 16.57μg·h^(−1)·mg cat.^(−1)and Faradaic effi ciency of 12.33%at−0.3 V versus reversible hydrogen electrode(ν***),with outstanding electrochemical and structural stability.

关键词： Polyoxometalates Electrocatalytic nitrogen reduction reaction Ternary oxide Electrocatalyst