Sada Krishnakanth, Gond Ritambhara, Bothra Neha, Pati Swapan K, Barpanda Prabeer
Faraday Materials Laboratory (FaMaL), Materials Research Centre, Indian Institute of Science, Bangalore 560012, India.
School of Advanced Materials (SAMat), Theoretical Science Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore 560064, India.
ACS Appl Mater Interfaces. 2022 Feb 23;14(7):8992-9001. doi: 10.1021/acsami.1c21481. Epub 2022 Feb 8.
Economic and sustainable (ecological) energy storage forms a major pillar of the global energy sector. Bifunctional electrocatalysts, based on oxygen electrolysis, play a key role in the development of rechargeable metal-air batteries. Pursuing precious metal-free economic catalysts, here, we report KCoPO pyrophosphate as a robust cathode for secondary zinc-air batteries with efficient oxygen evolution and oxygen reduction (OER||ORR) activity. Prepared by autocombustion, nanoscale KCoPO exhibited excellent oxygen reduction and evolution reactions among all phosphate-based electrocatalysts. In particular, the OER activity surpassed that of commercial RuO with low overpotential (0.27 V). First-principles calculations revealed that the bifunctional activity is rooted in the Co active site with the CoO local coordination in the most stable (110) surface. This nanostructured (tetragonal) pyrophosphate can be harnessed as an economic bifunctional catalyst for zinc-air batteries.
经济且可持续（生态）的储能是全球能源领域的一大支柱。基于氧电解的双功能电催化剂在可充电金属空气电池的发展中起着关键作用。为了寻求无贵金属的经济催化剂，在此我们报道焦磷酸钾钴（KCoPO）作为一种用于二次锌空气电池的稳健阴极，具有高效的析氧和氧还原（OER||ORR）活性。通过自燃烧制备的纳米级KCoPO在所有基于磷酸盐的电催化剂中表现出优异的氧还原和析氧反应。特别是，其OER活性超过了商业RuO，过电位低（0.27 V）。第一性原理计算表明，双功能活性源于在最稳定（110）表面具有CoO局部配位的Co活性位点。这种纳米结构（四方）焦磷酸盐可作为锌空气电池的经济双功能催化剂。
