Crisafulli Rudy, de la Hoz Antonio, de la Osa Ana Raquel, Sánchez Paula, de Lucas-Consuegra Antonio
Facultad de Ciencias y Tecnologías Químicas, Departamento de Ingeniería Química, Universidad de Castilla La-Mancha (UCLM), Av. Camilo José Cela 12, E-13071 Ciudad Real, España.
Facultad de Ciencias y Tecnologías Químicas, Departamento de Química Inorgánica, Orgánica, y Bioquímica, Universidad de Castilla La-Mancha (UCLM), Av. Camilo José Cela 10, E-13071 Ciudad Real, España.
ACS Sustain Chem Eng. 2025 Mar 5;13(13):4963-4974. doi: 10.1021/acssuschemeng.4c09249. eCollection 2025 Apr 7.
This study aims to systematically evaluate the competition between the oxygen evolution reaction (OER) and glucose oxidation reaction (GOR) in order to find the working conditions of a membrane-less glucose electrolyzer. For this purpose, a H electrochemical cell (H-cell) has been used to isolate the cathodic and anodic compartments. In the latter, in situ O measurements were performed by an optical sensor during different kinds of electrochemical experiments. As the glucose concentration increased, a progressive decrease in the O production rate was observed during the chronoamperometry step at 1.7 V vs RHE. At a glucose concentration of 40 mM, the OER can be entirely replaced by glucose oxidation on the Ni-based anodic catalyst. On the other hand, onset potentials for real O production were obtained at different glucose concentrations in order to maximize the electrocatalytic activity without any O production on the electrolyzer. During the operation of the electrolyzer at the selected conditions, instead of O, added value chemicals were obtained in the anodic compartment of the cell. These products were determined by H and C NMR, and the results showed that formic acid was the main product after 46 h of the electrolysis experiment (1.5 V vs RHE). Other products such as lactic acid and gluconic acid were also identified. The innovative experimental approach used in this study can be extended to other conditions, organic molecules, and catalysts. Furthermore, it serves as a starting point to establish a roadmap to a membrane-less electrolyzer to produce hydrogen and added value products.
本研究旨在系统评估析氧反应（OER）与葡萄糖氧化反应（GOR）之间的竞争，以找出无膜葡萄糖电解槽的工作条件。为此，采用了一个H型电化学电池（H-电池）来分隔阴极和阳极室。在阳极室中，在不同类型的电化学实验期间，通过光学传感器进行原位O测量。随着葡萄糖浓度的增加，在相对于可逆氢电极（RHE）为1.7 V的计时电流法步骤中，观察到O生成速率逐渐降低。在葡萄糖浓度为40 mM时，在镍基阳极催化剂上，OER可完全被葡萄糖氧化所取代。另一方面，在不同葡萄糖浓度下获得了实际O生成的起始电位，以便在电解槽上无任何O生成的情况下最大化电催化活性。在选定条件下运行电解槽期间，在电池的阳极室中获得的不是O，而是增值化学品。这些产物通过氢核磁共振（H NMR）和碳核磁共振（C NMR）进行测定，结果表明，在电解实验46小时后（相对于RHE为1.5 V），甲酸是主要产物。还鉴定出了其他产物，如乳酸和葡萄糖酸。本研究中使用的创新实验方法可扩展到其他条件、有机分子和催化剂。此外，它是建立无膜电解槽生产氢气和增值产品路线图的起点。
