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《Ceramics International》2022,48(14):20062-20069
Photocatalytic N2 fixation is a promising and sustainable manufacturing process of ammonia (NH3); however, the NH3 production rate by this method is very low, thus severely restricting further application of this sustainable technology. Therefore, developing an efficient photocatalyst for N2 fixation under mild conditions is urgently required. Herein, ferroelectric Bi2WO6 materials with different surface oxygen defects were prepared, and the concentration of corresponding defects was controlled by adjusting the thermal reduction time. The abundant oxygen defects in Bi2WO6 can provide more reactive sites to promote the effective adsorption of N2, and the photogenerated charge carrier can be efficiently separated benefiting from the internal electric field. These would weaken the N2 triple bond and reduce the activation energy barrier for the conversion of N2 to NH3 under mild conditions. In the absence of sacrificial agents and cocatalysts, the optimized Bi2WO6 with oxygen defects shows an indigenous NH3 yield of 132.175 μmol·g-1·L-1·h-1, which is more than two times higher than that of the original Bi2WO6. Surprisingly, the Bi2WO6 with oxygen defects produced more than eight times NH3 (471.13 μmol·g-1·L-1·h-1) than that of the original Bi2WO6 when assisted by an external magnetic field, thus providing a new perspective for further enhancing the N2 fixation performance. 相似文献
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《Ceramics International》2021,47(22):31852-31859
The primary purpose of this work is to introduce the second phase of graphene (G) into non-stoichiometric TiO1.80 successfully and optimize the thermoelectric properties of this composite material through high pressure and high temperature (HPHT) technology. The purpose of doping Ti powder under high pressure is to create a closed reducing atmosphere to change the ratio of titanium to oxygen in the titanium oxide base. The addition of graphene can considerably improve the electrical properties of the material and reduce its resistivity. An X-ray diffractometer, X-ray photoelectron spectrometer, scanning electron microscope, and transmission electron microscope were used to analyze and characterize the phase structure, chemical bond, micro morphology and crystal morphology of the samples. An abundance of grain boundaries and lattice dislocation defects can inhibit the lattice thermal conductivity. We also tested and analyzed the thermoelectric performance of the high-temperature and high-pressure synthetic samples through a variable temperature system. The variation of the absorption intensity of the ultraviolet UV spectrum with wavelength shows that high pressure can reduce the band gap, which is beneficial to the carrier transition and improves the conductivity of semiconductors. HPHT optimizes both the electrical and the thermal parameters of the sample. At a final sintering pressure of 5.0 GPa, the dimensionless figure of merit (zT) of the bulk composite material G/TiO1.80 was found to be 0.23 at 700 °C. 相似文献
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Lili Hao Jiaxiang Li Peng Wang Zongliang Wang Zhenxu Wu Yu Wang Zixue Jiao Min Guo Tongfei Shi Qigang Wang Yoshihiro Ito Yen Wei Peibiao Zhang 《Advanced functional materials》2021,31(15):2009661
The degradation behavior of implants is significantly important for bone repair. However, it is still unprocurable to spatiotemporally regulate the degradation of the implants to match bone ingrowth. In this paper, a magneto-controlled biodegradation model is established to explore the degradation behavior of magnetic scaffolds in a magnetothermal microenvironment generated by an alternating magnetic field (AMF). The results demonstrate that the scaffolds can be heated by magnetic nanoparticles (NPs) under AMF, which dramatically accelerated scaffold degradation. Especially, magnetic NPs modified by oleic acid with a better interface compatibility exhibit a greater heating efficiency to further facilitate the degradation. Furthermore, the molecular dynamics simulations reveal that the enhanced motion correlation between magnetic NPs and polymer matrix can accelerate the energy transfer. As a proof-of-concept, the feasibility of magneto-controlled degradation for implants is demonstrated, and an optimizing strategy for better heating efficiency of nanomaterials is provided, which may have great instructive significance for clinical medicine. 相似文献
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《Carbon》2015
The metal grid and reduced graphene oxide (RGO) are both promising transparent conductive materials for replacing the indium tin oxide (ITO) in flexible optoelectronics. However, the large empty area that exists in the grid together with the relatively high sheet resistance of RGO hinder both the materials for practical applications. In this work, we report for the first time a novel strategy for efficient combination of the metal grid and RGO by using a newly developed room-temperature reduction technique. The obtained RGO/metal grid hybrid films not only overcome the shortcomings of individual components but exhibit enhanced optical and electrical performances (Rs = 18 Ω sq−1 and T = 80%) and excellent flexural endurance. With this hybrid film as the window electrode, a highly flexible electrochromic device with excellent stability and ultra-fast response shorter than 60 ms has been successfully fabricated. Considering its high efficiency, high quality, low cost and large area, the strategy would be particularly useful for economically fabricating various metal grid/RGO films which are quite promising high performance transparent and conductive materials for next generation optoelectronic devices. 相似文献
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We report a simple processing method to simultaneously improve the efficiency and stability of organic solar cells (OSCs). Poly(4-styrene sulfonate)-doped poly(3,4-ethylenedioxy-thiophene (PEDOT:PSS), widely used as hole transport layer (HTL) in OSCs, tends to accelerate the degradation of devices because of its hygroscopic and acidic properties. In this regard, we have modified PEDOT:PSS to reduce its hygroscopic and acidic properties through a condensation reaction between PEDOT:PSS and poly(ethylene glycol) methyl ether (PEGME) in order to improve the efficiency and stability of OSCs. As a result, the power conversion efficiency (PCE) increased by 21%, from 2.57% up to 3.11%. A better energy level alignment by the reduced work function of the modified PEDOT:PSS with a highest occupied molecular orbital (HOMO) level of poly(3-hexylthiophene-2,5-diyl) (P3HT) is considered the origin of the improved the efficiency. The half-life of OSCs with PEDOT:PSS modified with PEGME buffer layer also increased up to 3.5 times compared to that of devices with pristine PEDOT:PSS buffer layer. 相似文献
10.
Guo-Yu Li Ya-Xin Zheng Fu-Zhou Sun Jian Huang Meng-Meng Lou Jing-Kai Gu Jin-Hui Wang 《International journal of molecular sciences》2015,16(9):22190-22204
This study aimed at investigating the possible mechanisms of hepatic protective activity of Cichorium intybus L. (chicory) in acute liver injury. Pathological observation, reactive oxygen species (ROS) detection and measurements of biochemical indexes on mouse models proved hepatic protective effect of Cichorium intybus L. Identification of active compounds in Cichorium intybus L. was executed through several methods including ultra performance liquid chromatography/time of flight mass spectrometry (UPLC-TOF-MS). Similarity ensemble approach (SEA) docking, molecular modeling, molecular docking, and molecular dynamics (MD) simulation were applied in this study to explore possible mechanisms of the hepato-protective potential of Cichorium intybus L. We then analyzed the chemical composition of Cichorium intybus L., and found their key targets. Furthermore, in vitro cytological examination and western blot were used for validating the efficacy of the selected compounds. In silico analysis and western blot together demonstrated that selected compound 10 in Cichorium intybus L. targeted Akt-1 in hepatocytes. Besides, compound 13 targeted both caspase-1 and Akt-1. These small compounds may ameliorate liver injury by acting on their targets, which are related to apoptosis or autophagy. The conclusions above may shed light on the complex molecular mechanisms of Cichorium intybus L. acting on hepatocytes and ameliorating liver injury. 相似文献