Template-Free Preparation of 3D Porous Co-Doped VN Nanosheet-Assembled Microflowers with Enhanced Oxygen Reduction Activity.
Haibo TangJunming LuoXin Long TianYuanyuan DongJing LiMingrui LiuLina LiuHuiyu SongShijun LiaoPublished in: ACS applied materials & interfaces (2018)
Developing cheap and stable electrocatalysts is considered the key factor to achieve the large-scale application of fuel cells. In this paper, three-dimensional (3D) porous Co-doped vanadium nitride (VN) nanosheet-assembled microflowers are prepared with a facile solvothermal approach followed by nitridation at 500 °C in NH3. It is found that the microflower morphology and the Co doping both significantly enhance the oxygen reduction reaction (ORR) performance of the materials. Because the unique 3D porous structure provides higher specific surface area and more active sites as well as enriching the d electrons of V via doping, Co also improves the intrinsic activity of VN. Our optimal V0.95Co0.05N microflowers achieve a half-wave potential for the ORR of up to 0.80 V in 0.1 M KOH solution, which is almost comparable to that of commercial 20% Pt/C. More importantly, the catalysts show superior durability with little current decline (less than 12%) during chronoamperometric evaluation for over 25 000 s. These features make the V0.95Co0.05N microflowers attractive for fuel cell applications.
Keyphrases
- metal organic framework
- highly efficient
- quantum dots
- induced apoptosis
- visible light
- transition metal
- single cell
- cell cycle arrest
- molecularly imprinted
- cell therapy
- room temperature
- reduced graphene oxide
- stem cells
- gold nanoparticles
- signaling pathway
- human health
- cell death
- mesenchymal stem cells
- risk assessment
- endoplasmic reticulum stress
- pi k akt
- mass spectrometry
- electron transfer