Au@NiS x Yolk@Shell Nanostructures as Dual‐Functional Electrocatalysts for Concomitant Production of Value‐Added Tartronic Acid and Hydrogen Fuel

• Published in: Advanced functional materials 2023-01, Vol.33 (4)
• Main Authors: Vo, Truong‐Giang, Tran, Giang‐Son, Chiang, Chao‐Lung, Lin, Yan‐Gu, Chang, Huai‐En, Kuo, Hsuan‐Hung, Chiang, Chia‐Ying, Hsu, Yung‐Jung
• Format: Article
• Language: English
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.202209386

Efficient glycerol electrooxidation reaction (GEOR) over gold@nickel sulfide (Au@NiS x ) yolk@shell nanostructures is demonstrated, achieving ≈50.4% glycerol conversion at 10 h, 92.6% selectivity toward three‐carbon products, and 90.7% total Faradaic efficiency. By regulating the electrode potential, tartronic acid (TART), one of the highest value‐added intermediates, can be produced with a selectivity as high as 43.1% and a yield of 45.6 µmol cm −2  h −1 . A combination of ex situ microstructural analysis, operando Raman, and operando X‐ray absorption measurements reveals a dynamic surface reconstruction course from Au@NiS x  to Au@NiS x /NiOOH during the glycerol oxidation process. The unique reconstructed architectures featuring conductive interior NiS x components and active surface high‐valence Ni 3+ species account for the superior GEOR performance. Further integration of GEOR with hydrogen evolution reaction is realized by employing Au@NiS x as both anode and cathode electrocatalysts in a two‐electrode configuration. Concomitantly production of TART and hydrogen fuel is accomplished. This study demonstrates that Au@NiS x not only can convert glycerol to TART with remarkable efficiency and selectivity, but also can produce hydrogen at a moderate level. The findings from this study can facilitate the development of dual‐functional electrocatalysts capable of producing high‐value products at both the cathode and anode sides.