One of the challenges in designing efficient electrocatalysts is rationalizing the impact of crystal and electronic structures on catalytic activity. Here, we synthesized four BaRuO₃ polymorphs with different structures and investigated the d-d interaction stemming from face-sharing RuO₆. The polymorph 9R-BaRuO₃ has the highest percentage of face-sharing RuO₆ octahedra and, therefore, the strongest d-d interaction; it shows the best activity and stability in catalyzing alkaline hydrogen evolution reactions (HER). Specifically, 9R-BaRuO₃ displays a small Tafel slope of 30 mV dec⁻¹ and a low overpotential of η₁₀ < 51 mV. This performance is attributed to its high intrinsic activity delivered by the d-d interaction and is intimately related to the crystal structure. The micron-sized 9R-BaRuO₃ powders are stable under industrial plasma spraying and carry a current density of 0.4 A/cm² @ 1.74 V in commercial alkaline water electrolyzers. The results on catalytic activities and crystal structure provide insight for designing better electrocatalysts for practical applications.

中文翻译：

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具有共面基序的钌酸钙钛矿用于碱性析氢


设计高效电催化剂的挑战之一是合理化晶体和电子结构对催化活性的影响。在这里，我们合成了四种具有不同结构的BaRuO ₃多晶型物，并研究了由共面RuO ₆引起的dd相互作用。多晶型9 R -BaRuO ₃具有最高比例的共面RuO ₆八面体，因此具有最强的dd相互作用；它在催化碱性析氢反应（HER）方面表现出最佳的活性和稳定性。具体地，9 R -BaRuO ₃显示出30 mV dec ^-1的小塔菲尔斜率和η ₁₀ < 51 mV 的低过电势。这种性能归因于其由dd相互作用提供的高内在活性，并且与晶体结构密切相关。微米级9R -BaRuO ₃粉末在工业等离子喷涂下稳定，并且在商业碱性水电解槽中在1.74V下承载0.4A/cm ²的电流密度。催化活性和晶体结构的结果为设计更好的实际应用电催化剂提供了见解。