المؤلفون: Heming Deng, Haoshuang Gu

المصدر: Journal of CO2 Utilization, Vol 83, Iss , Pp 102796- (2024)

مصطلحات موضوعية: MXene, NH2-UIO-66, Structural regulation, Flexible membrane, Gas separation, Technology

الوصف: Two-dimensional membranes are considered the next generation separation membrane with great application potential due to their excellent separation performance, good mechanical strength and thermal stability compared with traditional membrane materials. In this work, the flexible NH2-UIO-66@MXene membrane was successfully prepared for gas separation by loading NH2-UIO-66 particles onto Ti3C2 nanosheets based on an in-situ growth strategy. A LiF-HCl mixed solution was used as the etchant to obtain the Ti3C2 nanosheets. The loading of NH2-UIO-66 particles can regulate the interlayer spacing of Ti3C2 nanosheets, improving the specific surface area of Ti3C2 and the adsorption capacity for specific gases. The -NH2 group in NH2-UIO-66 enabled preferential adsorption of CO2 over H2, and the CO2 molecules adsorbed in the channel can even block the molecules passing through, increasing the resistance of CO2 diffusion. As a result, the NH2-UIO-66@Ti3C2 hybrid membrane realizes the selective separation of H2/CO2 mixed gas, and the separation selectivity is as high as 155. The gas separation selectivity and permeation of the final prepared NH2-UIO-66@MXene were enhanced and exceeded the upper limit of Robeson upper bound (2017).

وصف الملف: electronic resource

العلاقة: http://www.sciencedirect.com/science/article/pii/S2212982024001318Test; https://doaj.org/toc/2212-9839Test

الوصول الحر: https://doaj.org/article/5729cbfd15644b3996c1d43f8dd25536Test

المؤلفون: Jingyan Liu, Shi Zeng, Mingrui Zhang, Juan Xiong, Haoshuang Gu, Zhao Wang, Yongming Hu, Xianghui Zhang, Yi Du, Long Ren

المصدر: Advanced Science, Vol 10, Iss 36, Pp n/a-n/a (2023)

مصطلحات موضوعية: liquid metals, liquid‐solid interface, piezoelectric composites, piezoelectric energy harvester, Science

الوصف: Abstract Integrating nanomaterials into the polymer matrix is an effective strategy to optimize the performance of polymer‐based piezoelectric devices. Nevertheless, the trade‐off between the output enhancement and stability maintenance of piezoelectric composites usually leads to an unsatisfied overall performance for the high‐strength operation of devices. Here, by setting liquid metal (LM) nanodroplets as the nanofillers in a poly(vinylidene difluoride) (PVDF) matrix, the as‐formed liquid‐solid/conductive‐dielectric interfaces significantly promote the piezoelectric output and the reliability of this piezoelectric composite. A giant performance improvement featured is obtained with, nearly 1000% boosting on the output voltage (as high as 212 V), 270% increment on the piezoelectric coefficient (d33∼51.1 pC N−1) and long‐term reliability on both structure and output (over 36 000 cycles). The design of a novel heterogenous interface with both mechanical matching and electric coupling can be the new orientation for developing high performance piezoelectric composite‐based devices.

وصف الملف: electronic resource

العلاقة: https://doaj.org/toc/2198-3844Test

الوصول الحر: https://doaj.org/article/57b89604b4f44e08a2c621faf323e1a6Test

المؤلفون: Shulin Yang, Huan Yin, Zhao Wang, Gui Lei, Huoxi Xu, Zhigao Lan, Haoshuang Gu

المصدر: Frontiers in Chemistry, Vol 11 (2023)

مصطلحات موضوعية: In2O3, nanostructrues, gas sensor, sensing mechanism, review, Chemistry, QD1-999

الوصف: Effective detection of toxic and hazardous gases is crucial for ensuring human safety, and high-performance metal oxide-based gas sensors play an important role in achieving this goal. In2O3 is a widely used n-type metal oxide in gas sensors, and various In2O3 nanostructures have been synthesized for detecting small gas molecules. In this review, we provide a brief summary of current research on In2O3-based gas sensors. We discuss methods for synthesizing In2O3 nanostructures with various morphologies, and mainly review the sensing behaviors of these structures in order to better understand their potential in gas sensors. Additionally, the sensing mechanism of In2O3 nanostructures is discussed. Our review further indicates that In2O3-based nanomaterials hold great promise for assembling high-performance gas sensors.

وصف الملف: electronic resource

العلاقة: https://www.frontiersin.org/articles/10.3389/fchem.2023.1174207/fullTest; https://doaj.org/toc/2296-2646Test

الوصول الحر: https://doaj.org/article/fd8ebd667ff84d7c8b369f1d417707b7Test

المؤلفون: Shensong Wang, Changqin Tan, Linfeng Fei, Haitao Huang, Shujun Zhang, Hao Huang, Xinyi Zhang, Qiu-an Huang, Yongming Hu, Haoshuang Gu

المصدر: Frontiers in Chemistry, Vol 8 (2020)

مصطلحات موضوعية: β-Ni(OH)2, ultra-thin nanoplates, energy density, flexibility, all-solid-state supercapacitors, Chemistry, QD1-999

الوصف: The all-solid-state flexible supercapacitor (AFSC), one of the most flourishing energy storage devices for portable and wearable electronics, attracts substantial attentions due to their high flexibility, compact size, improved safety, and environmental friendliness. Nevertheless, the current AFSCs usually show low energy density, which extremely hinders their practical applications. Herein, ultra-thin β-Ni(OH)2 nanoplates with thickness of 2.4 ± 0.2 nm are in-situ grown uniformly on Ni foam by one step hydrothermal treatment. Thanks to the ultra-thin nanostructure, β-Ni(OH)2 nanoplates shows a specific capacitance of 1,452 F g−1 at the scan rate of 3 mV s−1. In addition, the assembled asymmetric AFSC [Ni(OH)2//Activated carbon] shows a specific capacitance of 198 F g−1. It is worth noting that the energy density of the AFSC can reach 62 Wh kg−1 while keeping a high power density of 1.5 kW kg−1. Furthermore, the fabricated AFSCs exhibit satisfied fatigue behavior and excellent flexibility, and about 82 and 86% of the capacities were retained after 5,000 cycles and folding over 1,500 times, respectively. Two AFSC in series connection can drive the electronic watch and to run stably for 10 min under the bending conditions, showing a great potential for powering portable and wearable electronic devices.

وصف الملف: electronic resource

العلاقة: https://www.frontiersin.org/articles/10.3389/fchem.2020.602322/fullTest; https://doaj.org/toc/2296-2646Test

الوصول الحر: https://doaj.org/article/dfd146b763a74ed3b4bf504879699b0eTest

المؤلفون: Shulin Yang, Gui Lei, Huoxi Xu, Zhigao Lan, Zhao Wang, Haoshuang Gu

المصدر: Nanomaterials, Vol 11, Iss 4, p 1026 (2021)

مصطلحات موضوعية: metal oxide, heterojunctions, gas sensor, sensing mechanism, review, Chemistry, QD1-999

الوصف: The construction of heterojunctions has been widely applied to improve the gas sensing performance of composites composed of nanostructured metal oxides. This review summarises the recent progress on assembly methods and gas sensing behaviours of sensors based on nanostructured metal oxide heterojunctions. Various methods, including the hydrothermal method, electrospinning and chemical vapour deposition, have been successfully employed to establish metal oxide heterojunctions in the sensing materials. The sensors composed with the built nanostructured heterojunctions were found to show enhanced gas sensing performance with higher sensor responses and shorter response times to the targeted reducing or oxidising gases compare with those of the pure metal oxides. Moreover, the enhanced gas sensing mechanisms of the metal oxide-based heterojunctions to the reducing or oxidising gases are also discussed, with the main emphasis on the important role of the potential barrier on the accumulation layer.

وصف الملف: electronic resource

العلاقة: https://www.mdpi.com/2079-4991/11/4/1026Test; https://doaj.org/toc/2079-4991Test

الوصول الحر: https://doaj.org/article/71a34035d53e49aeb5e16cda6ed5a2a2Test

المؤلفون: Ming Liu, Caochuang Wang, Pengcheng Li, Liang Cheng, Yongming Hu, Yao Xiong, Shishang Guo, Haoshuang Gu, Wanping Chen

المصدر: Materials, Vol 14, Iss 9, p 2123 (2021)

مصطلحات موضوعية: hydrogen, sensing, SnO2, Pt, crystal defect, sintering, Technology, Electrical engineering. Electronics. Nuclear engineering, TK1-9971, Engineering (General). Civil engineering (General), TA1-2040, Microscopy, QH201-278.5, Descriptive and experimental mechanics, QC120-168.85

الوصف: Many low-dimensional nanostructured metal oxides (MOXs) with impressive room-temperature gas-sensing characteristics have been synthesized, yet transforming them into relatively robust bulk materials has been quite neglected. Pt-decorated SnO2 nanoparticles with 0.25–2.5 wt% Pt were prepared, and highly attractive room-temperature hydrogen-sensing characteristics were observed for them all through pressing them into pellets. Some pressed pellets were further sintered over a wide temperature range of 600–1200 °C. Though the room-temperature hydrogen-sensing characteristics were greatly degraded in many samples after sintering, those samples with 0.25 wt% Pt and sintered at 800 °C exhibited impressive room-temperature hydrogen-sensing characteristics comparable to those of their counterparts of as-pressed pellets. The variation of room-temperature hydrogen-sensing characteristics among the samples was explained by the facts that the connectivity between SnO2 grains increases with increasing sintering temperature, and Pt promotes oxidation of SnO2 at high temperatures. These results clearly demonstrate that some low-dimensional MOX nanocrystals can be successfully transformed into bulk MOXs with improved robustness and comparable room-temperature gas-sensing characteristics.

وصف الملف: electronic resource

العلاقة: https://www.mdpi.com/1996-1944/14/9/2123Test; https://doaj.org/toc/1996-1944Test

الوصول الحر: https://doaj.org/article/5c410ba40b604592807ccccdd65a0622Test

المؤلفون: Yaxuan Cai, Shijun Luo, Zhao Wang, Juan Xiong, Haoshuang Gu

المصدر: Journal of Materiomics, Vol 3, Iss 2, Pp 130-134 (2017)

مصطلحات موضوعية: First-principles study, Monte Carlo, Trichloroacetamide, TCAA, Organic ferroelectrics, Materials of engineering and construction. Mechanics of materials, TA401-492

الوصف: The electronic structure and ferroelectric mechanism of trichloroacetamide were studied using first principles calculations and density functional theory within the generalized gradient approximation. Using both Bader charge and electron deformation density, large molecular spontaneous polarization is found to originate from the charge transfer cause by the strong “push-pull” effect of electron-releasing interacting with electron-withdrawing groups. The intermolecular hydrogen bonds, NH⋯O, produce dipole moments in adjacent molecules to be aligned with each other. They also reduce the potential energy of the molecular chain threaded by hydrogen bonds. Due to the symmetric crystalline properties, however, the polarization of trichloroacetamide is mostly compensated and therefore small. Using the Berry Phase method, the spontaneous polarization of trichloroacetamide was simulated, and good agreement with the experimental values was found. Considering the polarization characteristics of trichloroacetamide, we constructed a one-dimensional ferroelectric Hamiltonian model to calculate the ferroelectric properties of TCAA. Using the Hamiltonian model, the thermal properties and ferroelectricity of trichloroacetamide were studied using the Monte Carlo method, and the Tc value was calculated.

وصف الملف: electronic resource

العلاقة: http://www.sciencedirect.com/science/article/pii/S2352847816301034Test; https://doaj.org/toc/2352-8478Test

الوصول الحر: https://doaj.org/article/bca02909c2894cc58c58dbd38dc5827fTest

المؤلفون: Yue Zhang, Yizhi Wang, Zhihong Xiong, Yongming Hu, Weixing Song, Qiu-an Huang, Xiaoxing Cheng, Long-Qing Chen, Chunwen Sun, Haoshuang Gu

المصدر: ACS Omega, Vol 2, Iss 3, Pp 793-799 (2017)

مصطلحات موضوعية: Chemistry, QD1-999

وصف الملف: electronic resource

العلاقة: https://doaj.org/toc/2470-1343Test

الوصول الحر: https://doaj.org/article/964612c6745f4b64b293472b59ce7c73Test

المؤلفون: Yongming Hu, Zhao Wang, Haoshuang Gu

المصدر: Sensors, Vol 12, Iss 5, Pp 5517-5550 (2012)

مصطلحات موضوعية: hydrogen gas sensor, semiconductor oxides, nanostructure, thin films, one-dimensional nanostructures, Chemical technology, TP1-1185

الوصف: Recently, the hydrogen gas sensing properties of semiconductor oxide (SMO) nanostructures have been widely investigated. In this article, we provide a comprehensive review of the research progress in the last five years concerning hydrogen gas sensors based on SMO thin film and one-dimensional (1D) nanostructures. The hydrogen sensing mechanism of SMO nanostructures and some critical issues are discussed. Doping, noble metal-decoration, heterojunctions and size reduction have been investigated and proved to be effective methods for improving the sensing performance of SMO thin films and 1D nanostructures. The effect on the hydrogen response of SMO thin films and 1D nanostructures of grain boundary and crystal orientation, as well as the sensor architecture, including electrode size and nanojunctions have also been studied. Finally, we also discuss some challenges for the future applications of SMO nanostructured hydrogen sensors.

وصف الملف: electronic resource

العلاقة: http://www.mdpi.com/1424-8220/12/5/5517Test; https://doaj.org/toc/1424-8220Test

الوصول الحر: https://doaj.org/article/230a79986eef4268a873a51148e3d28aTest

المؤلفون: Yanan Zou, Yue Zhang, Yongming Hu, Haoshuang Gu

المصدر: Sensors, Vol 18, Iss 7, p 2072 (2018)

مصطلحات موضوعية: UV detectors, wide bandgap semiconductor, nanowire, Chemical technology, TP1-1185

الوصف: Ultraviolet (UV) detectors have attracted considerable attention in the past decade due to their extensive applications in the civil and military fields. Wide bandgap semiconductor-based UV detectors can detect UV light effectively, and nanowire structures can greatly improve the sensitivity of sensors with many quantum effects. This review summarizes recent developments in the classification and principles of UV detectors, i.e., photoconductive type, Schottky barrier type, metal-semiconductor-metal (MSM) type, p-n junction type and p-i-n junction type. The current state of the art in wide bandgap semiconductor materials suitable for producing nanowires for use in UV detectors, i.e., metallic oxide, III-nitride and SiC, during the last five years is also summarized. Finally, novel types of UV detectors such as hybrid nanostructure detectors, self-powered detectors and flexible detectors are introduced.

وصف الملف: electronic resource

العلاقة: http://www.mdpi.com/1424-8220/18/7/2072Test; https://doaj.org/toc/1424-8220Test

الوصول الحر: https://doaj.org/article/12290b5a5ad6461090e7dad80e1fbd19Test