Renewable energy sources like solar and wind power are gaining popularity. Due to renewable energy's inherent instability, developing efficient electrochemical CO2 reduction reactions or methane oxidation to methanol for energy storage has become a grand challenge research topic due to its significance for alleviating climate change and mitigating greenhouse gases (GHG).
Recent studies have involved three types of trinuclear copper cluster catalysts [1]. These include membranes enriched particulate methane monooxygenase (pMMO) from Methylococcus capsulatus (Bath) and a recombinant PmoB protein over-expressed in Escherichia coli. In addition to these biological catalysts, biomimetic nanomaterials designated as [Cu3(7-N-Etppz)]-MCM-41, which were created by immobilizing the [CuIICuII(O)CuII(7-N-Etppz)](ClO4)2 complex, where the ligand "7-N-Etppz" refers to organic compound 3,3’-(1,4-diazepane-1,4-diyl)bis[1-(4-ethylpiperazine-1-yl)propan-2-ol], into porous MCM-41. These trinuclear copper complex catalysts were subjected to a cathodic surface to initiate the dioxygen chemistry for methane activation. This approach enabled the voltage-gated electrocatalysis of methane oxidation to methanol using tri-copper clusters, resulting in remarkable improvements in catalyst performance for methane oxidation. Unprecedented turnover frequencies (TOF>40 min–1) and promising product throughputs (turnover numbers >30,000 in 12 h) were achieved for this challenging chemical transformation in water under ambient conditions. This technology is green and suitable for the on-site direct conversion of methane into methanol at room temperature, which can control methane emissions from stationary sources.
Additionally, a porous nanosheet of bismuth oxychloride (BiOCl) catalyst was developed for an efficient CO2 reduction reaction to formate [2]. Using the cationic surfactant cetyltrimethylammonium bromide (CTAB) maintains the structural integrity of the Bi nanosheet, enhancing electrochemical activity while reducing charge resistance.
Our ultimate goal is to advance energy storage applications by improving the efficiency of formate/formic acid or methanol production for long-term conversions in heterogeneous electrochemical catalytic platforms.