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Efficient glycerol electrooxidation reaction (GEOR) over gold@nickel sulfide (Au@NiSx) 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@NiSx to Au@NiSx/NiOOH during the glycerol oxidation process. The unique reconstructed architectures featuring conductive interior NiSx components and active surface high‐valence Ni3+ species account for the superior GEOR performance. Further integration of GEOR with hydrogen evolution reaction is realized by employing Au@NiSx 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@NiSx 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.

Glycerol Electrooxidation In article number 2209386, Yung‐Jung Hsu, Chia‐Ying Chiang, and co‐workers demonstrate practical use of Au@NiSx yolk@shell nanostructures for efficient glycerol electrooxidation (GEOR). Further integration of GEOR with hydrogen evolution reaction is realized by employing Au@NiSx as both anode and cathode electrocatalysts in a two‐electrode configuration. Concomitant production of tartronic acid, one of the highest value‐added intermediates, and hydrogen fuel can be accomplished.

In this work, we report for the first time a comprehensive operando investigation of the intricate correlation between dynamic phase evolution and glycerol electrooxidation reaction (GEOR) performance across three primary MnO 2 crystallographic phases (α-, β-, and γ-MnO 2 ). The results showed that all three electrocatalysts exhibited comparable selectivity toward three-carbon products (∼90%), but γ-MnO 2 exhibited superior performance, with a low onset potential of ∼1.45 V RHE , the highest current density of ∼1.9 mA cm −2 at 1.85 V RHE , and reasonable stability. Operando Raman spectroscopy revealed the potential-induced surface reconstruction of different MnO 2 structures from which a correlation among the applied potential, electrocatalytic activity, and product distribution was identified. The higher the applied potential, the greater conversion from the original structure to δ-MnO 2 , resulting in lower C−C cleavage and higher 3C product selectivity. This study not only provides a systematic understanding of structure-controlled electrocatalytic activity for high selectivity toward 3C products of MnO 2 but also contributes to the development of a non-noble and environmentally friendly catalyst for valorizing glycerol.