In situ growth of polyimide nanoarrays on conductive carbon supports for high-rate charge storage and long-lived metal-free cathodes

Author(s):  
Qing Zhang ◽  
Yi He ◽  
Guanyu Lin ◽  
Xiaolan Ma ◽  
Zongying Xiao ◽  
...  

Polyimide nanoarrays on conductive carbon supports with high-rate charge storage arising from high-speed electron transport, abundant porous channels and highly exposed redox-active sites.

2022 ◽  
Author(s):  
Feng Min ◽  
Zhengqing Wei ◽  
Zhen Yu ◽  
Yu-Ting Xiao ◽  
Shien Guo ◽  
...  

Both efficient charge separation and sufficiently exposed active sites are critical limiting for solar-driven organic contaminants degradation. Herein, we describe a hierarchical heterojunction photocatalyst fabricated by in situ growth of...


Author(s):  
Weinong W. Chen ◽  
Matthew C. Hudspeth ◽  
Ben Claus ◽  
Niranjan D. Parab ◽  
John T. Black ◽  
...  

Split Hopkinson or Kolsky bars are common high-rate characterization tools for dynamic mechanical behaviour of materials. Stress–strain responses averaged over specimen volume are obtained as a function of strain rate. Specimen deformation histories can be monitored by high-speed imaging on the surface. It has not been possible to track the damage initiation and evolution during the dynamic deformation inside specimens except for a few transparent materials. In this study, we integrated Hopkinson compression/tension bars with high-speed X-ray imaging capabilities. The damage history in a dynamically deforming specimen was monitored in situ using synchrotron radiation via X-ray phase contrast imaging. The effectiveness of the novel union between these two powerful techniques, which opens a new angle for data acquisition in dynamic experiments, is demonstrated by a series of dynamic experiments on a variety of material systems, including particle interaction in granular materials, glass impact cracking, single crystal silicon tensile failure and ligament–bone junction damage.


2020 ◽  
Vol 819 ◽  
pp. 153359 ◽  
Author(s):  
Yuanhua Xiao ◽  
Jiyuan Zhang ◽  
Dangcheng Su ◽  
Aiqin Zhang ◽  
Qingxian Jin ◽  
...  

NANO ◽  
2020 ◽  
Vol 15 (10) ◽  
pp. 2050125
Author(s):  
Hui’e Wang

Here, a novel material consisting of black phosphorus (BP) and nickel-dimethylglyoxime nanorods was successfully prepared via a facile in situ calcination strategy, which possesses efficient catalytic activity for hydrogen production from water splitting. The reason for this phenomenon was explained by a series of characterization technologies such as SEM, TEM, XRD, UV–Vis, XPS and photoelectrochemical. We demonstrated that the fast e− transport channels were provided by the formed hollow structure of C@Ni-D nanorods, the highly exposed active sites on C@Ni-BP nanorods benefiting from the direct in situ growth of BP, the resulted synergetic effects of C@Ni-D-2 nanorods and BP achieved a better performance of photocatalytic hydrogen production from water splitting. The optimal hydrogen generation of C@Ni-BP-2 nanorods could reach up to 600[Formula: see text][Formula: see text]mol within 180[Formula: see text]min and the rate of hydrogen production did not decrease significantly after four repeated reaction cycles. This work may offer new direction in situ growth of novel catalysts for achieving highly efficient hydrogen production.


2021 ◽  
Author(s):  
Javier Villalobos ◽  
Diego Gonzales-Flores ◽  
Roberto Urcuyo ◽  
Mavis L. Montero ◽  
Götz Schuck ◽  
...  

<p>The requirements for beneficial materials restructuring into a higher performance OER electrocatalyst are still a largely open question. Here we use Erythrite (Co<sub>3</sub>(AsO<sub>4</sub>)<sub>2 </sub>8H<sub>2</sub>O) as a Co-based OER electrocatalyst to evaluate its catalytic properties during in-situ restructuring into an amorphous Co-based catalyst in four different electrolytes at pH 7. Using diffraction, microscopy and spectroscopy, we observed a strong effect in the restructuring kinetics depending of the anions in the electrolyte. Only carbonate electrolyte could activate the catalyst electrode, which we relate to its slow restructuring kinetics. While its turnover frequency (TOF) reduced from 2.84 O<sub>2 </sub>Co<sup>-1 </sup>s<sup>-1</sup> to a constant value of 0.10 O<sub>2</sub> Co<sup>-1 </sup>s<sup>-1</sup> after ~ 300 cycles, the number of redox active sites continuously increased, which explained the current increase of around 100%. The final activated material owns an adequate local order, a high Co oxidation state and a high number of redox-active Co ions, which we identify as the trinity for enhancing the OER activity. Thus, this work provides new insights into for the rational design of high-performance OER catalysts by electrochemical restructuring.</p>


Author(s):  
Baining Lin ◽  
Yuwei Liu ◽  
Yaping Li ◽  
Fan Xu ◽  
Yingping Zou ◽  
...  

Direct dehydrogenation of ethylbenzene to styrene catalyzed by metal-free materials is one of the most challenging topics in the chemical industry currently. Here, PBN@Al2O3(N) synthesized by in-situ growth of phosphorus-doped...


Author(s):  
Xiubei Yang ◽  
Chao Lin ◽  
Diandian Han ◽  
Gaojie Li ◽  
Chao Huang ◽  
...  

Covalent organic frameworks (COFs) with reversible redox-active sites showed great potential application in constructing electrode materials of lithium-ion batteries (LIBs), whereas their further application is largely restricted by the poor...


2020 ◽  
Vol 7 (11) ◽  
pp. 1902767 ◽  
Author(s):  
Xiaobing Tang ◽  
Wei Chen ◽  
Dan Wu ◽  
Aijing Gao ◽  
Gaomin Li ◽  
...  

2019 ◽  
Vol 2 (6) ◽  
pp. 4195-4204 ◽  
Author(s):  
Hua An ◽  
Xiaoqing Yan ◽  
He Li ◽  
Bolun Yang ◽  
Jinjia Wei ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document