Modifying acidic oxygen production properties of PbO 2 by porous Mn 2 O 3 microspheres for boosting stability

Designing active and durable cost-effective electrocatalysts for catalyzing the oxygen evolution reaction (OER) under a strongly acidic environment is a highly promising approach for OER-associated sustainable energy supplies. Herein, a Pb-Sn-Ca/α-PbO 2 /β-PbO 2 -Mn 2 O 3 (PSC/PbO 2 -Mn 2 O 3 ) composite electrode is fabricated via a simple two-step process. First, porous Mn 2 O 3 microspheres are synthesized by the solvothermal method. Then, a PSC/PbO 2 -Mn 2 O 3 composite electrode with a special embedded structure is prepared through the introduction of Mn 2 O 3 by composite electrodeposition. The low OER overpotential (621 mV) of the PSC/PbO 2 -Mn 2 O 3 (12 g L −1 ) composite electrode is reduced by 445 mV compared with that of the industrial Pb-(0.76 wt%) Ag electrode at a current density of 50 mA cm −2. In addition, it shows a service life of up to 91 h at a high operation current density of 1.5 A cm −2 in acidic media (3.06 g L −1 H + ), which indicates its excellent stability. Therefore, this work not only demonstrates a design for a durable and high-efficiency electrocatalyst for acidic water oxidation but also provides strategies for the synthesis of advanced electrocatalytic electrodes.