A series of Cobalt-polyoxometalates (Co-POM) have been incorporated into carbon paste electrodes as insoluble salts of Cs⁺ or Ba²⁺. Specifically, we included the lacunary Keggin-type derivatives [Co(H₂O)(PW₁₁O₃₉)]^5– (CoPW₁₁), [Co(H₂O)(SiW₁₁O₃₉)]^6– (CoSiW₁₁), [Co(H₂O)(CoW₁₁O₃₉)]^7– (CoCoW₁₁), [Co₄(H₂O)₂(PW₉O₃₄)₂]^10– (Co₄P₂W₁₈), [Co₄(H₂O)₂(SiW₉O₃₄)₂]^12– (Co₄Si₂W₁₈), and [Co₉(H₂O)₆(OH)₃(HPO₄)₂(PW₉O₃₄)₃]^16– (Co₉); and the lacunary Dawson-Wells derivative [Co₄(H₂O)₂(P₂W₁₅O₅₆)₂]^16– (Co₄P₄W₃₀). The activity and stability of these composite electrodes towards water oxidation in acidic media (pH < 1) was examined by electrochemical methods and post-catalytic characterization. Our results indicate the stability of these catalysts in these conditions depends on composition, since only those species containing P^V as heteroatom appeared to be stable. All Si^IV and Co^III derivates showed rapid decomposition, regardless their nuclearity or molecular structure. All stable derivatives exhibited consistent activity, favored by high nuclearity and overall total charge, with Keggin derivatives being intrinsically more active than the corresponding Dawson-Wells analogues.

一系列钴多金属氧酸盐（Co-POM）已作为Cs ⁺或Ba ^2+的不溶盐掺入碳糊电极中。具体来说，我们包括了隐伏的Keggin型衍生物[Co（H ₂ O）（PW ₁₁ O ₃₉）] ^5–（CoPW ₁₁），[Co（H ₂ O）（SiW ₁₁ O ₃₉）] ^6–（CoSiW ₁₁），[Co（H ₂ O）（CoW ₁₁ O ₃₉）] ^7–（CoCoW ₁₁），[Co ₄（H ₂ O）₂（PW ₉ O ₃₄）₂ ] ^10–（Co ₄ P ₂ W ₁₈），[Co ₄（H ₂ O）₂（SiW ₉ O ₃₄）₂ ] ^12–（Co ₄ Si ₂ W ₁₈）和[Co ₉（H ₂ O）₆（OH）₃（HPO ₄）₂（PW ₉ O ₃₄）₃ ] ^16–（Co ₉）; 和空洞的Dawson-Wells衍生物[Co ₄（H ₂ O）₂（P ₂ W ₁₅ O ₅₆）₂ ] ^16–（Co ₄ P ₄ W ₃₀）。通过电化学方法和催化后表征研究了这些复合电极在酸性介质（pH <1）中对水氧化的活性和稳定性。我们的结果表明，在这些条件下，这些催化剂的稳定性取决于组成，因为只有那些含有^PV作为杂原子的物种才是稳定的。所有Si ^IV和Co^III衍生物显示快速分解，无论其核数或分子结构如何。所有稳定的衍生物均表现出一致的活性，受到高核能和总体总电荷的促进，其中Keggin衍生物本质上比相应的Dawson-Wells类似物更具活性。