查找使用阿拉丁产品的科研文献

Co nanoparticles supported on three-dimensionally N-doped holey graphene aerogels for electrocatalytic oxygen reduction

Kai-Wen Cao,Hao Huang,Fu-Min Li,Hong-Chang Yao,Juan Bai,Pei Chen,Pu-Jun Jin,Zi-Wei Deng,Jing-Hui Zeng,Yu Chen

The reactive and stable catalysts for the oxygen reduction reaction are highly desirable for low temperature fuel cells. The commercial oxygen reduction reaction electrocatalysts generally reply on noble metal based nanomaterials, which suffer from inherent cost and selectivity issues. At present, it still remains challenge for designing efficient non-noble metal-based oxygen reduction reaction electrocatalysts. Herein, we successfully synthesize Co nanoparticles supported on three-dimensionally N-doped holey graphene aerogels hybrids by the high-temperature calcination of the graphene aerogels-polyallylamine-Co II hybrids. The component optimized hybrids show the excellent electrocatalytic activity for oxygen reduction reaction in alkaline media, which is comparable to commercial Pt/C electrocatalyst. Meanwhile, the hybrids also show eminent tolerance for CO and methanol, attributing to their excellent oxygen reduction reaction selectivity. The three-dimensionally interconnected structure of graphene aerogels, N-doping, uniform dispersion and high crystallinity of Co nanoparticles, and holey structure of graphene contribute to the striking oxygen reduction reaction activity of hybrids.

The effect of different n-butanol-fatty acid methyl esters (FAME) blends on puffing characteristics

Yu Zhang,Ronghua Huang,Shijie Xu,Yuhan Huang,Sheng Huang,Yinjie Ma,Zhaowen Wang

The droplet suspension technology was used under the condition of atmospheric pressure and 873   K. The n -butanol concentration ranged from 0% to 75% to investigate the effect of n -butanol concentration on the puffing characteristics of a n -butanol-fatty acid methyl esters (FAME) droplet. Experimental results showed that BUT25, BUT50 and BUT75 (BUT’XX’ represented XX% n -butanol by mass fraction in the n -butanol-FAME blend) underwent three phases, namely the transient heating phase, fluctuation evaporation phase and equilibrium evaporation phase. The temperatures of BUT25, BUT50 and BUT75 were similar at the start and end of the transient heating phase. The duration of BUT75’s transient heating phase was much longer than that of BUT25 and BUT50. Therefore, the evaporation cooling of BUT75 was the most prominent because the temperature growth rate of BUT75 was significantly less than that of BUT25 and BUT50. Furthermore, the fluctuation evaporation phase could be divided into the strong and weak fluctuation stages. The violent fluctuation was only observed in the strong fluctuation stage. The weak fluctuation stage was similar as the stable evaporation. The active rupture was found in the strong fluctuation stage and the passive rupture was found in the weak fluctuation stage. The active and passive ruptures were caused by the fast bubble expansion and surface evaporation respectively. In addition, many periodic processes were contained in the strong fluctuation stage. The similarity degree of the periodic process showed a slump and a gradual increase, which were caused by bubble expansion and droplet recovery respectively. The bubble expansion of BUT50 was greater than that of BUT75. Significant bubble expansion led to the violent deformation after bubble rupture. The recovery time of BUT50 was longer than that of BUT75. Therefore, the similarity degree of BUT50 exhibited a wavy structure and BUT75 displayed a comb-like structure in the strong fluctuation stage.

Facile synthesis and catalytic activity of well-defined amphiphilic block copolymers based on N-vinylimidazolium

Chang Peng,Kai Huang,Mingsong Han,Wei Meng,Yuanqin Xiong,Weijian Xu

Well-defined amphiphilic block copolymers, poly(styrene)- b -poly( N -vinylimidazole) (PS- b -PVim), were successfully synthesized by macromolecular design via interchange of the xanthates/reversible addition–fragmentation chain transfer (RAFT) polymerization. The structure of the copolymer based on Vim can be well controlled, and the molecular weight distribution was relatively narrow (PDI = 1.24). The size and morphology of the aggregates of the amphiphilic copolymers were investigated by dynamic light scattering and transmission electron microscope, the results implied that the uniform spheroidal micelles consisting of PS core and PVim corona were assembled, and the catalytic activities of PS- b -PVim for the hydrolysis of p -nitrophenyl acetate at different temperatures were also investigated by high-performance liquid chromatograph (HPLC); the catalytic activities of diblock copolymers were prominently improved compared with that of PVim homopolymers. Moreover, the catalytic activities of the copolymers followed the Arrhenius behavior in the wide experimental temperature range. Copyright © 2013 John Wiley & Sons, Ltd.

Electrochemical performance of in situ LiFePO4 modified by N-doped graphene for Li-ion batteries

Gui-Yang Luo,Yi-Jing Gu,Yuan Liu,Zi-Liang Chen,Yong-lin Huo,Fu-Zhong Wu,Yi Mai,Xin-Yi Dai,Yong Deng

LiFePO 4 modified by N-doped graphene (NG) with a three-dimensional conductive network structure was synthesized via a one-step in situ hydrothermal method . The effects of N amount of NG on the phase structure, morphology, and electrochemical properties of LiFePO 4 are investigated in this study. X-ray diffraction (XRD) results show that doping suitable N amounts in NG do not alter the crystal structure of LiFePO 4, and scanning electron microscopy (SEM) images show that NG can slightly reduce the particle size of LiFePO 4 . The high-resolution transmission electron microscopy (HRTEM) results show that the LiFePO 4 particles are well covered and connected by NG. The electrochemical performance confirms that LiFePO 4 modified by 20% N-doped graphene (named LFP/NG-4) displays a perfect specific capacity of 166.6 mAh·g −1 at a rate of 0.2C and can reach 125 mAh·g −1 at a rate of 5 C. Electrochemical impedance spectroscopy (EIS) results illustrate that the charge transfer resistance value of the LFP/NG-4 composite is only 58.6 Ω, which is very low compared with LiFePO 4 . Cyclic voltammetry (CV) tests indicate that the addition of 20% N-doped graphene can effectively reduce electrode polarization and improve reversibility. The LFP/NG-4 composite with a three-dimensional conductive network structure can be regarded as a promising cathode material for Li-ion batteries.

Violet Arsenic Phosphorus: Switching p-Type into High Performance n-Type Semiconductor by Arsenic Substitution

Zhai Rui,Wen Zhuorui,Zhao Xuewen,She Junyi,Gu Mengyue,Bu Fanqi,Huang Chang,Meng Guodong,Cheng Yonghong,Zhang Jinying

Violet arsenic phosphorus (VP-As) single crystals were synthesized and characterized by single crystal X-ray diffraction to be P 83.4 As 0.6 (CSD-2408761), the P12 is occupied by arsenic/phosphorus as a mixed occupancy site. The p-type VP has been switched into n-type VP-As, the effective electron mass was significantly reduced and resulted in high electron mobility of 2622.503 cm 2 V −1 s −1 . High electron mobility of 137.06 cm 2 V −1 s −1 has been achieved from field effect transistor, much higher than the hole mobility of VP.

A self-assembled molecule directs ordered α-FAPbI3 for n-i-p perovskite solar cells

He Qingyun,Wang Junbo,Wu Mengyang,Zhong Chongyu,Li Lei,Zhao Xiangru,Ding Mengzhu,Yang Pinghui,Li Renzhi,Huang Wei,Qin Tianshi,Wang Fangfang

Formamidinium lead iodide (FAPbI 3 ) perovskite is a leading candidate for high-efficiency solar cells, but its application is hindered by the kinetic instability of its α-phase crystallization. Here, a highly effective strategy for directing the ordered crystallization of α-FAPbI 3 in the n-i-p architecture is developed by incorporating a self-assembled molecule (SAM) into the anti-solvent, unlike conventional phosphate-based SAMs requiring polar protic solvents, the -SCN SAM are processed from non-polar, aprotic solvents compatible with perovskite surfaces. An in-situ formed, self-assembled layer acts as a dynamic template, guiding the top-down crystallization process to yield highly ordered α-phase films. Through a series of in-situ measurements, it is rigorously demonstrated that this SAM treatment suppresses undesirable intermediate phases, accelerates the δ-to-α transition, and strategically slows crystal growth, promoting highly ordered films. This meticulously designed strategy culminates in high-quality perovskite films, enabling single-junction devices with a champion power conversion efficiency (PCE) of 26.18% (certified at 25.67%) and mini-modules with a PCE of 21.70%. These results underscore the power of directed self-assembly in fabricating highly efficient and stable n-i-p perovskite solar cells.

N-doped carbon dots from pericarpium citri reticulatae for wide linear range sensing of hydroquinone

Peng Du,Zhengkun Chu,Jing Zhang,Jieyu Ma,Feng Cao,Jie Liu

Hydroquinone (H2Q) present in water is becoming a growing problem in both daily life and industry, with various harmful effects on human health. Therefore, the detection of H2Q is very important. The Carbon dot-based sensor is considered an effective method to detect H2Q. In this work, Pericarpium citri reticulatae carbon dots (P-CDs) were synthesized by a one-pot hydrothermal method for wide linear sensing of H2Q. An orthogonal test was used to expand the active site and fluorescence properties of P-CDs. Under optimal conditions, the P-CDs exhibit an extremely stable blue fluorescence and a quantum yield (QY) of up to 15.4%. In the range of 5–1000 μM, compared with the currently reported carbon dot-based H2Q sensors, the fluorescence intensity (FL) of P-CDs shows good linearity with the variation of H2Q concentration and a higher linear range. Moreover, the sensor demonstrates a low detection limit of 0.058 μM. The possible detection mechanism is based on the synergistic action of static quenching and IFE. This method has been successfully applied to the determination of H2Q in real samples, and the P-CDs-based sensor has the potential to detect H2Q in various complex scenes.

Discovery of N-hydroxy-4-(1H-indol-3-yl)butanamide as a histone deacetylase inhibitor

Jiang Bian,Yepeng luan,Chunbo Wang,Lei Zhang

Antibiotic-free antimicrobial functionalization of PEEK via UV-induced self-initiation and N-halamine grafting

Ziying Cheng,Yansheng Huang,Zhigang Zhao,Songnan Shao,Zitong Zhao,Xiaoshuai Peng,Baorong He,Zhen Chang

Background Implant-associated infection remains a major challenge in orthopedic surgery. Although polyether ether ketone (PEEK) is widely used owing to its favorable mechanical properties and radiolucency, its intrinsic bioinertness renders it highly susceptible to bacterial colonization. Developing a durable, antibiotic-free antibacterial surface modification for PEEK with translational relevance remains clinically desirable. Methods In this study, a covalently grafted N-halamine–functionalized PEEK surface (PEEK- g -PAM-NCl) was fabricated via a UV-induced self-initiated polymerization strategy. The antibacterial performance was systematically evaluated against Staphylococcus aureus and Escherichia coli using time–kill assays, live/dead staining, and antibacterial tests under protein-rich conditions. Biocompatibility and osteogenic potential were assessed in vitro using hBM-MSCs. In vivo antibacterial efficacy and biocompatibility were further investigated using subcutaneous implant-associated infection model in the C57BL/6J mice and femoral osteomyelitis model in the SD rat. Results PEEK- g -PAM-NCl exhibited sustained and effective antibacterial activity against both Gram-positive and Gram-negative bacteria, achieving >98% bacterial reduction in vitro, including under protein-rich conditions. Time–kill assays revealed a pronounced time-dependent bactericidal effect. In vivo, PEEK- g -PAM-NCl significantly reduced bacterial burden, inflammatory infiltration, and infection-associated tissue damage compared with pristine PEEK, effectively preventing chronic osteomyelitis features. Importantly, no abnormal systemic inflammatory response or local tissue toxicity was observed. In vitro osteogenic assessments demonstrated that the antibacterial modification did not adversely affect osteogenic differentiation. Conclusion This study demonstrates that covalent N-halamine functionalization endows PEEK with sustained, antibiotic-free antibacterial activity while preserving biocompatibility performance. PEEK- g -PAM-NCl represents a promising translational strategy for preventing implant-associated infections in orthopedic applications. The translational potential of this article This study presents an antibiotic-free antibacterial surface modification strategy for PEEK implants based on UV-induced covalent grafting of N-halamine polymers. The robust antibacterial efficacy, preserved cytocompatibility, and supportive bone-related biological responses suggest potential applicability in preventing implant-associated infections in orthopedic settings. This work provides a feasible surface engineering approach that may be further optimized and translated toward clinically relevant load-bearing implants.

Strong metal-support interaction enhanced acetylene hydrochlorination stability over Cu1-N-C single-site catalysts

Chang Liu,Jianlin Cao,Yuxiang Bao,Juncong Yuan,Yuanning Yue,Yibin Liu,Xiaobao Chen,Yinming Guo,Chaohe Yang,Baorui Li,Xiang Feng,De Chen

Cu-based catalysts present a promising alternative to toxic mercuric chloride (HgCl 2 ) in acetylene hydrochlorination owing to their cost-efficiency and environmental compatibility. However, the dispersion and leaching of active sites under operational conditions hinders its application. Herein, we designed a lignin-supported Cu 1 N single-site copper catalyst (Cu 1 /L-CN) by site-anchored strategy which employed pyrrolic N functional groups to anchor and inhibit the aggregation of Cu atoms by strong metal-support interaction. Based on kinetics study and in-situ characterizations, it is found that the Cu 1 /L-CN catalyst inhibits the formation of complexes between copper and acetylene, suppressing over-adsorption of acetylene and undesired side reactions. Accordingly, the Cu 1 /L-CN catalyst demonstrated excellent catalytic activity and a low deactivation rate constant (k D  = 0.016 h −1 ) with significantly reduced carbon deposition. This work will provide a new approach to the design of mercury-free catalysts toward industrial production of vinyl chloride from the acetylene hydrochlorination.

Interface-tuned capacitance enhancement in N-P Co-doped carbon membrane/PANI hybrids for supercapacitors

Cai Jiangtao,Liu Yi,Zhou Xiaonan,Hu Yehao,Yang Jin,Wang Zhiqiang,Sun Wenbin,Zhang Yating

Conducting polyaniline (PANI) and porous carbon fibrous membranes to construct composite electrode materials is one of the hotspots for preparing high-performance supercapacitors. The key is realizing the homogeneous dispersion of the two materials, carbon/PANI, and the connection interface with considerable firmness and strength. Therefore, based on the interfacial covalent bonding strategy, the N-P co-doped carbon membrane and PANI hybrid (NPCM@PANI) materials were designed and constructed. NPCMs were used as substrates to functionalize with nitric acid and ND42, and then co-aniline in situ on the surface of NPCMs. This approach aimed to obtain a hybrid material with high specific capacitance, using NPCM as the substrate. The resulting NPCM@PANI hybrids have a specific capacitance of up to 552 F/g (1 A/g), a small equivalent series resistance of 1.1 Ω and a low transfer diffusion resistance of about 1 Ω in 1 M H 2 SO 4 electrolyte. The capacitance performance is still 78% after 1,000 cycles, which provides excellent capacitance properties. Graphical abstract

Black electrochromic devices based on a highly conductive n-type polymer and a bilayer structure

Weiwei Jin,Tiancheng Jin,Zhicheng Hu,Haoran Tang,Fei Huang

Organic electrochromic materials are particularly distinguished by their adjustable coloration and solution processability, showing significant potential in the domains of smart windows and automotive applications. Conductive polymer-based electrochromic devices can achieve color-rich and high-performance devices by altering the material structure. However, traditional electrochromic devices face challenges such as non-black coloration, cumbersome preparation process and electrode corrosion problems. To address these issues, this study applies a novel n-type conducting polymer poly(benzodifurandione) (PBFDO) as one electrochromic layer and introduces a ferrocene-based redox couple into the ion-transporting electrolyte film. The resulting bilayer black devices achieve complete electrochromic cycles via PBFDO reduction and redox couple oxidation. High-quality PBFDO films with controllable thickness, neutral gray-black color, and robust adhesion to ITO substrates were confirmed. The devices exhibit broad-spectrum modulation, good electrochromic performance, excellent cyclic stability (50 000 cycles), and superior heat insulation performance. This innovative approach streamlines the fabrication process on a large scale and offers substantial support for their practical deployment.