Electrospining Machine: Preparation of Joule Thermal Flash of Carbon-Supported Transition Metal Catalyst and Studyon its Hydrogen Evolution Performance

Background

Carbon-loaded transition metal sulfide and high-entropy alloy sulfide catalysts were synthesized in situ relying on an electrospinning machine using the Joule heat flash method, and their hydrogen evolution properties were investigated, solving the problems of high energy consumption and the need for binders in the conventional synthesis methods, while ensuring high catalytic activity, electrical conductivity and stability.

Method

Carbon-supported transition metal sulfide and high entropy alloy sulfide catalysts were synthesized in situ using the Joule thermal flash method, and their hydrogen evolution performance was studied, which solved the problems of high energy consumption and the need for binders in traditional synthesis methods while ensuring high catalytic activity, conductivity and stability.

Research Highlights

Innovative manufacturing technology: Three-dimensional self-supported carbon-loaded transition metal catalysts were prepared relying on the Scale-up Electrospinning machine using an emerging Joule thermal flash method, which is fast, efficient, low-energy consuming, and low-cost compared to the traditional hydrothermal and pyrolysis methods. This method also eliminates the use of binders, thus improving the conductivity and stability of the catalysts.

Figure 1. Joule thermal flash evaporation platform circuit diagram

Binary transition metal sulfides (CoNiSx/CC)：

Figure 2. Design and production process of porous spiral LIG sheets

Figure 3. Sample images of a 60mF capacitor at 60V flash voltage (a) before flashing; (b) at the beginning of flashing; (c) at the end of flashing; and (d-h) at the cooling stage.

Figure 4. SEM image of carbon cloth after 60mF capacitor 40V flash voltage treatment

Figure 5. (a) SEM image of M5Sx/CC-60V-60mF; (b) SEM image of thiourea/CC; (c) SEM image of high entropy alloy sulfide particles on the carbon fiber surface

Excellent material performance (good catalytic performance and stability):

Two new composite materials, binary transition metal sulfide (CoNiSx/CC) and high entropy alloy sulfide (M5Sx/CC), exhibited good electrocatalytic activity and stability in the hydrogen evolution reaction by water electrolysis. In particular, in 1M KOH alkaline electrolyte, the overpotential required for the CoNiSx/CC composite material to reach 10 mA·cm^-2 was only 112 mV, showing excellent catalytic performance.

Figure 6. CoNiSx/CC (a) Electrochemical double layer capacitance (Cdl) corresponding to the CV curve; (b) Linear sweep polarization curves before and after 1000 cyclic voltammetry tests

Figure 7. M5Sx/CC (a) Electrochemical double layer capacitance (Cdl) corresponding to the CV curve; (b) Linear sweep polarization curve before and after 1000 cyclic voltammetry tests

Improve production efficiency and reduce energy consumption:

Joule thermal flash evaporation can synthesize nano transition metal compounds in situ on carbon-based materials. This method is fast and efficient, with fast heating and cooling speed, avoiding the problems of high energy consumption and long time consumption of traditional methods.

Conclusion:

 This study shows that the three-dimensional mesh structure of the matrix material carbon cloth is conducive to the exposure of active sites and improves the conductivity of the composite material. This structural design not only enhances the performance of the catalyst, but also provides new ideas for future catalyst design and provides an important reference for the development of the hydrogen energy field.

Paper link: https://kns.cnki.net/kcms2/article/abstract?v=KetWmXlLxldcsH_ag3HusUHZdKwYixEObqlPTKiEw5DXSaHJVyz_-NIsVG8CeNFpxjr1K-OnTJUFo5l64zzTjFfC55GXxa5ohqWvRpZ-cZK0KDBJX2m-2DUEwgjJRFQGow4ABIyBz8U9xwSlMA0EuRQMYXt5FIxIMngf_umERkM2BlY64-mSiEFycr6LifDBmJgvLs0Us-I=&uniplatform=NZKPT&language=CHS