ScholarWorks@동국대학교

초록

Progress in acidic water splitting has remained limited because of low oxygen evolution reaction (OER) activities, sluggish reaction kinetics, and severe catalyst degradation. Thus, a highly active and durable OER catalyst is required for the commercialization of acidic water electrolyzers. Here, we report t-phase ruthenium oxide atomic layers implanted on Mo2TiC2Tx MXene (RAL-M) as a model electrocatalyst for the OER in acidic media, which exhibits a remarkable mass activity (6.2 A mg- 1), excellent turnover frequency (TOF; 2.4 s-1), and negligible loss of durability after 22 h in a two-electrode cell configuration. The mass activity and TOF of RAL-M are 150 times (RuO2-Premetek Co.) and 540 times (RuO2-Sigma-Aldrich) greater than the industrially adopted electrocatalysts at pH 0.48. Computational calculations show that the ruthenium active sites of RAL-M have a strong affinity to oxygen species (e.g., OH*, O*, and OOH*), which efficiently adapts water dissociation and favors both the adsorbate evolution and lattice oxygen mechanistic pathways to accelerate the OER.

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