Chuanxuan Zhou,Mengyun Wang,Cheng Huang,Fuchao Yang
Real-time and high efficient monitoring of triethylamine (TEA) is crucial for chemical industry production and environmental safety. However, it is still challenge to achieve ppb level detection efficiently and exact understanding. In this paper, bimetallic PtPd sensitized vacancies enriching WO 3 hollow microspheres materials were designed and harvested an ultra-high response and selectivity to TEA gas. It was found that the oxygen vacancies of WO 3 hollow microspheres can be enhanced by the introduction of Fe element. Furthermore, the PtPd@Fe-WO 3 exhibited a remarkable sensing response (409.58–20 ppm TEA), which was 4.85 times higher than that of Fe-WO 3 -based sensor and 21.28 times higher than that of pure WO 3 sensor. This further enhancement of response can be attributed to the strong catalytic spillover effect and electron sensitization of Pt as well as the reversible redox cycling properties of Pd. In addition, the PtPd@Fe-WO 3 material also possesses fast response, excellent selectivity, long-term stability, and a low detection limit of 69.59 ppb, and the gas sensing mechanism was understood by density functional theory (DFT). The proposed bimetallic PtPd sensitized oxygen vacancies enriching WO 3 system is a promising candidate for building high-performance TEA sensors for practical applications.
Control of the chemical composition and morphology of electrochemical nanocatalysts is a promising strategy to effectively promote electrocatalytic oxidation in direct methanol fuel cells (DMFCs). Here, we describe a general soft-template-directed one-pot synthesis for the formation of bimetallic mesoporous nanospheres (MNSs) with cylindrically open mesoporous nanochannels. Three-dimensional (3D) well-dispersed bimetallic PtPd MNSs were prepared through in situ co-reduction of Pt and Pd precursor on the soft-templating structural directing amphiphilic surfactant of bisoctyl dimethyl ammonium chloride (BDAC) under optimal reaction conditions without using any toxic organic solvent. Owing to the synergistic advantages in structure and composition, the as-prepared mesoporous morphology of the bimetallic PtPd MNSs has more active sites and accelerates electron/mass transfer. Especially, the Pt 1 Pd 4.8 MNSs possessed a mass activity of 3450 mA mg metal −1 and specific activity of 163.8 mA cm −2 , which are 6.63 and 20.76 times higher than commercial Pt/C (520 mA mg Pt −1 and 7.89 mA cm −2 ). Therefore, it shows outstanding catalytic activity and stability toward electrocatalytic oxidation of methanol under alkaline conditions.
Li Ma,Liya Zhou,Ying He,Lihui Wang,Zhihong Huang,Yanjun Jiang,Jing Gao
Mesoporous bimetallic PtPd nanoflowers (MPtPdN) were synthesized by a surfactant-directing method. The MPtPdN was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and wide-angle X-ray diffraction (XRD). The use of MPtPdN as a platform for the indirect electrochemical detection of organophosphate pesticides (OPs) via enzymatic inhibition pathway was demonstrated. Due to the nanostructure of MPtPdN and the synergy effect of the noble metal nanoparticles, a novel and sensitive acetylcholinesterase (AChE) biosensor for OPs detections based on MPtPdN and enzyme inhibition was prepared. The inhibition of omethoate exhibited a linear relationship from 4.7×10 −11 to 4.7×10 −8 M with a detection limit of 1.7×10 −12 M (S/N=3). The proposed AChE biosensor was reliable and can be used to measure the concentration of omethoate in different spiked samples with high accuracy and satisfactory recovery. The preparation of biosensors based on the MPtPdN can be further extended to construct many other important enzyme biosensors.
危险品化学品经营许可证（带存储）