Remote tracking the variation of air quality in an effective way will be highly helpful to decrease the health risk of human short-and long-term exposures to air pollution.However,high power consumption and poor sensi...Remote tracking the variation of air quality in an effective way will be highly helpful to decrease the health risk of human short-and long-term exposures to air pollution.However,high power consumption and poor sensing performance remain the concerned issues,thereby limiting the scale-up in deploying air quality tracking networks.Herein,we report a standalone-like smart device that can remotely track the variation of air pollutants in a power-saving way.Brevity,the created smart device demonstrated satisfactory selectivity(against six kinds of representative exhaust gases or air pollutants),desirable response magnitude(164–100 ppm),and acceptable response/recovery rate(52.0/50.5 s),as well as linear response relationship to NO2.After aging for 2 weeks,the created device exhibited relatively stable sensing performance more than 3 months.Moreover,a photoluminescence-enhanced light fidelity(Li-Fi)telecommunication technique is proposed and the Li-Fi communication distance is significantly extended.Conclusively,our reported standalone-like smart device would sever as a powerful sensing platform to construct high-performance and low-power consumption air quality wireless sensor networks and to prevent air pollutant-induced diseases via a more effective and low-cost approach.展开更多
The flexible transparent conductive films （FrCFs） of silver nanowire-polyethylene terephthalate （AgNW- PET） were prepared by a facile method including vacuum filtration and mold transferring. The effect of silver ...The flexible transparent conductive films （FrCFs） of silver nanowire-polyethylene terephthalate （AgNW- PET） were prepared by a facile method including vacuum filtration and mold transferring. The effect of silver nanowire weight density on the optical and electrical properties of films, as well as the electrical percolation was investigated. The obtained typical AgNW-PET film exhibited high figure of merit of 31.3 × 10^-3 Ω^-1 with low sheet resistance of 4.95 D sq^-1 and high transparency at 550 nm of 83.0% （excluding PET substrate）. The resulting FTCFs based on PET substrate with high transmittance and low sheet resistance have a great potential in the application of high-performance flexible electronics and photovoltaic devices.展开更多
Surfactant-free and binder-free antimony-doped tin oxide （ATO） transparent conducting thin films were fabricated through spin coating and rapid annealing processes, in which nanosheets were assembled into a compact ...Surfactant-free and binder-free antimony-doped tin oxide （ATO） transparent conducting thin films were fabricated through spin coating and rapid annealing processes, in which nanosheets were assembled into a compact structure via self-contracting high pressure. The mechanism of this compact thin film for- mation was further proposed and analyzed. The compact ATO thin film had a low root mean square （RMS） roughness of 5.03 nm. This surfactant-free and binder-free compact ATO thin film delivered low resistivity of 3.04 × 10^-2 Ω cm, stable resistivity which only increased 13% after exposing in 65% RH air for half a month, high transmittance of 92.70% at 550 nm, and high band gap energy of 4.07 eV. This effective strategy will provide new insight into the synthesis of low-cost and high-performance compact thin films.展开更多
Metal and alloy nanoparticles synthesized by chemical reduction have attracted increasing attention due to their superior physical,chemical,and biological properties.However,most chemical synthesis processes rely on t...Metal and alloy nanoparticles synthesized by chemical reduction have attracted increasing attention due to their superior physical,chemical,and biological properties.However,most chemical synthesis processes rely on the use of harsh reducing agents and complicated chemical ingredients.Herein,we report a novel reduction-agent-free and surfactant(stabilizer)-free strategy to synthesize Cu,Ag,Au,Cu-Pt,Cu-Au,Cu-Au-Pt-Pd,and Au-Pt-Pd-Cu nanoparticles by ultrasound-assisted dealloying of Mgbased metallic glasses.The formation mechanism of the metal and alloy nanoparticles is revealed by a detailed investigation of sequential intermediate products.We demonstrate that the glass-liquid phase transition of the initially dealloying metallic glasses,together with the synergistic effect of dealloying and ultrasound-driven ligament-breakage of small enough nanoporous intermediates,play key roles in preparing the uniformly dispersed metal and alloy nanoparticles.This approach greatly simplifies the up-scaling synthesis of monometallic and bimetallic nanoparticles,and also provides a general strategy for synthesizing unprecedented multimetallic nanoparticles.展开更多
One-dimensional silver nanocrystals （AgNCs） have been prepared by a polyol process using sodium hydroxide and nitric acid at a constant silver source concentration. Results indicate that the acidity- basicity plays ...One-dimensional silver nanocrystals （AgNCs） have been prepared by a polyol process using sodium hydroxide and nitric acid at a constant silver source concentration. Results indicate that the acidity- basicity plays an important role in silver-nanocrystal formation. Different morphologies of AgNCs were synthesized by changing the NaOH or HNO3 amount. We demonstrate that nearly monodisperse silver nanocrystals can be separated from polydisperse samples using density gradient centrifugation separation （DGCS）. We also demonstrate that the separated AgNCs can be used as substrates for surface- enhanced Raman scattering （SERS） spectroscopy. The separation approach provides a method of improving the nanocrystal quality produced by large-scale synthetic methods.展开更多
基金the financial support for this research from the National Key Research and Development Program of China(Grant No.2017YFA0205301)National Natural Science Foundation of China(Grant No.61771267,61774106)+6 种基金Oceanic Interdisciplinary Program of Shanghai Jiao Tong University(Grant No.BX2020208)Shanghai Natural Science Foundation(Grant No.86973)Natural Science Foundation of Ningbo City(Grant No.2017A610229)National Postdoctoral Program for Innovative Talents(Grant No.BX20190205)Special fund for science and technology innovation of Shanghai Jiao Tong University(Grant No.YG2017MS70)Shanghai Municipal Bureau of Economy and Information Technology(Grant No.XC-ZXSJ-02-2016-05)China Postdoctoral Science Foundation.
文摘Remote tracking the variation of air quality in an effective way will be highly helpful to decrease the health risk of human short-and long-term exposures to air pollution.However,high power consumption and poor sensing performance remain the concerned issues,thereby limiting the scale-up in deploying air quality tracking networks.Herein,we report a standalone-like smart device that can remotely track the variation of air pollutants in a power-saving way.Brevity,the created smart device demonstrated satisfactory selectivity(against six kinds of representative exhaust gases or air pollutants),desirable response magnitude(164–100 ppm),and acceptable response/recovery rate(52.0/50.5 s),as well as linear response relationship to NO2.After aging for 2 weeks,the created device exhibited relatively stable sensing performance more than 3 months.Moreover,a photoluminescence-enhanced light fidelity(Li-Fi)telecommunication technique is proposed and the Li-Fi communication distance is significantly extended.Conclusively,our reported standalone-like smart device would sever as a powerful sensing platform to construct high-performance and low-power consumption air quality wireless sensor networks and to prevent air pollutant-induced diseases via a more effective and low-cost approach.
基金financial support from the National Natural Science Foundation of China(Grant No.21203226)Ningbo Key Laboratory of Silicon and Organic Thin Film Optoelectronic Technologies(Grant No.2014A22002)
文摘The flexible transparent conductive films （FrCFs） of silver nanowire-polyethylene terephthalate （AgNW- PET） were prepared by a facile method including vacuum filtration and mold transferring. The effect of silver nanowire weight density on the optical and electrical properties of films, as well as the electrical percolation was investigated. The obtained typical AgNW-PET film exhibited high figure of merit of 31.3 × 10^-3 Ω^-1 with low sheet resistance of 4.95 D sq^-1 and high transparency at 550 nm of 83.0% （excluding PET substrate）. The resulting FTCFs based on PET substrate with high transmittance and low sheet resistance have a great potential in the application of high-performance flexible electronics and photovoltaic devices.
文摘Surfactant-free and binder-free antimony-doped tin oxide （ATO） transparent conducting thin films were fabricated through spin coating and rapid annealing processes, in which nanosheets were assembled into a compact structure via self-contracting high pressure. The mechanism of this compact thin film for- mation was further proposed and analyzed. The compact ATO thin film had a low root mean square （RMS） roughness of 5.03 nm. This surfactant-free and binder-free compact ATO thin film delivered low resistivity of 3.04 × 10^-2 Ω cm, stable resistivity which only increased 13% after exposing in 65% RH air for half a month, high transmittance of 92.70% at 550 nm, and high band gap energy of 4.07 eV. This effective strategy will provide new insight into the synthesis of low-cost and high-performance compact thin films.
基金financially supported by Guangdong Major Project of Basic and Applied Basic Research,China(No.2019B030302010)the National Natural Science Foundation of China(Nos.51671206 and 51871056)+1 种基金the foundation from the Department of Education of Guangdong Province(No.2018KZDXM069)the Natural Science Foundation of Guangdong Province(No.2019B030302010)。
文摘Metal and alloy nanoparticles synthesized by chemical reduction have attracted increasing attention due to their superior physical,chemical,and biological properties.However,most chemical synthesis processes rely on the use of harsh reducing agents and complicated chemical ingredients.Herein,we report a novel reduction-agent-free and surfactant(stabilizer)-free strategy to synthesize Cu,Ag,Au,Cu-Pt,Cu-Au,Cu-Au-Pt-Pd,and Au-Pt-Pd-Cu nanoparticles by ultrasound-assisted dealloying of Mgbased metallic glasses.The formation mechanism of the metal and alloy nanoparticles is revealed by a detailed investigation of sequential intermediate products.We demonstrate that the glass-liquid phase transition of the initially dealloying metallic glasses,together with the synergistic effect of dealloying and ultrasound-driven ligament-breakage of small enough nanoporous intermediates,play key roles in preparing the uniformly dispersed metal and alloy nanoparticles.This approach greatly simplifies the up-scaling synthesis of monometallic and bimetallic nanoparticles,and also provides a general strategy for synthesizing unprecedented multimetallic nanoparticles.
基金supported by the National Natural Science Foundation of China(Nos.21205127,21203226 and 21377063)
文摘One-dimensional silver nanocrystals （AgNCs） have been prepared by a polyol process using sodium hydroxide and nitric acid at a constant silver source concentration. Results indicate that the acidity- basicity plays an important role in silver-nanocrystal formation. Different morphologies of AgNCs were synthesized by changing the NaOH or HNO3 amount. We demonstrate that nearly monodisperse silver nanocrystals can be separated from polydisperse samples using density gradient centrifugation separation （DGCS）. We also demonstrate that the separated AgNCs can be used as substrates for surface- enhanced Raman scattering （SERS） spectroscopy. The separation approach provides a method of improving the nanocrystal quality produced by large-scale synthetic methods.
