Oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) represent two of the most critical O2 redox reactions in low temperature electrocatalysis. They play critical roles in multiple electrochemical processes involving oxygen and water, and have been widely investigated. Due to the sluggish natures of both reactions, they typically require expensive platinum group metals (PGMs) to accelerate the catalytic processes. For example, Pt is known as the best ORR catalyst in PEM fuel cell applications, whereas Ir is the most effective OER catalyst in PEM water electrolyzer. The high costs of both PGM materials, however, add significant barrier to the widespread implementation of these technologies. During the last two decades, substantially amount of effort has been invested in searching for low-cost replacements, or PGM-free catalysts for these applications. An area of particular advancement is the single-atom ORR catalysis. More recently, an increasing amount of studies are now published in PGM-free OER catalyst for hydrogen production through water electrolysis.Another fast developing area of electrocatalysis is CO2 reduction reaction (CO2RR), which promises to electrochemically convert CO2 to fuels and chemicals using renewable electricity. While CO2RR via 2-electron transfer, such as the conversion of CO2 to CO or formate, has been proven high selective with fast kinetics, conversions to C2+ chemicals require significantly stronger binding between the catalytic site and CO2 to complete multiple electron transfers (8 to 12) and C-C bond coupling steps, therefore are more challenging.At Argonne National Laboratory, we actively participated and contributed the PGM-free and low-PGM catalyst for ORR and OER catalysis in the acidic media using metal-organic framework (MOF) [1, 2, 3] and porous organic polymer (POP) [4] as the catalyst precursors. More recently, we develop a new amalgamated lithium metal (ALM) synthesis method to preparing highly selective and active CO2RR catalyst for CO2+ chemicals such as ethanol production. [5] In this presentation, I will discuss some of our recent advancements in catalyst design, synthesis and mechanistic understanding, including advanced structure characterization and computational modeling. I will also share my perspective on the promise and challenges in these catalyst developments. Acknowledgement: This work is supported by U. S. Department of Energy, Fuel Cell Technologies Office through Office of Energy Efficiency and Renewable Energy and is supported by Office of Science, U.S. Department of Energy under Contract DE-AC02-06CH11357.[1] “Cobalt Imidazolate Framework as Precursor for Oxygen Reduction Reaction Electrocatalyst”, Shengqian Ma, Gabriel Goenaga, Ann Call and Di-Jia Liu, Chemistry: A European Journal, (2011) 17, 2063 – 2067[2] L. Chong, J. Wen, J. Kubal, F. G. Sen, J. Zou, J. Greeley, M. Chan, H. Barkholtz, W. Ding, and D.-J. Liu, “Ultralow-loading Platinum-Cobalt Fuel Cell Catalysts Derived from Imidazolate Frameworks,” Science (2018) 362, 1276[3] “Impacts of Imidazolate Ligand to Performance of Zeolitic-Imidazolate Framework-Derived Oxygen Reduction Catalysts”, Hao Wang, Lauren R. Grabstanowicz, Heather M. Barkholtz, Dominic Rebollar, Zachary B. Kaiser, Dan Zhao, Biao-Hua Chen, and Di-Jia Liu, ACS Energy Lett. 2019, 4, 10, 2500-2507[4] “Highly-Active and “Support-free” Oxygen Reduction Catalyst Prepared from Ultrahigh Surface Area Porous Polyporphyrin” Shengwen Yuan, Jiang-Lan Shui,Lauren Grabstanowicz, Chen Chen,Sean Commet, Briana Reprogle, Tao Xu, Luping Yu and Di-Jia Liu, Angew. Chem. Int. Ed., 2013, 52(32), 8349–8353[5] “Highly selective electrocatalytic CO2 reduction to ethanol by metallic clusters dynamically formed from atomically dispersed copper” Haiping Xu, Dominic Rebollar, Haiying He, Lina Chong, Yuzi Liu, Cong Liu, Cheng-Jun Sun, Tao Li, John V. Muntean, Randall E. Winans, Di-Jia Liu and Tao Xu, (2020) Nature Energy, 5, 623–632