TIFR
Department of Chemical Sciences
School of Natural Sciences

January 15, 2021 at 2.30 pm (via Zoom)

Title :

Earth Abundant Metal Functionalized Graphene Based Hybrid Electrocatalyst for CO2 Reduction

Abstract :

Rapidly increasing CO2 in the atmosphere is becoming the big challenge of scientific community globally because of serious environmental and societal issues. The major contributor for CO2 is mostly from combustion of fossil fuel during industrialization. On the other end there is an increase in demand of energy because of globalization responsible for increase in level in atmosphere. It motivates to search for the ways to reduction of CO2 to other chemical intermediates and/or back to fuel. Among the existing conversion ways electrocatalytic approach by selecting appropriate cathode electrode nanomaterial is one of the most promising and cost effective approach to convert CO2 to variety of hydrocarbons. [1]

Further nanomaterials for electro catalysis are superior because of its compare to bulk large surface area, hence less utilization, spatial confinement, and many more. Another issue of it requires wide electrochemical window which controls the use of aqueous electrolytes. Depending up on electron transfer in electrochemistry of CO2 there are different types of product formed such as Hydrocarbons, alcohols, Formic acid etc. [2] In addition to this other structural issues of CO2 includes solubility, and comfortably of other reduced intermediates results into hamper its conversion. To overcome this barrier, we herewith used as-synthesized Graphene oxide decorated metal oxide hybrid electrocatalytic system for the reduction of CO2 considering their synergetic effect to useful product formic acid. [3] Moreover, as a one of the active component g-carbon nitrite (g-C3N4) is having highly polymeric class and consists of carbon and nitrogen with different types of allotropes with sheet-like structure, synthesized by simple way from commercially accessible and low-cost materials. Again, N-doping materials are having more active sites and a large number of defects because of Sp3 carbon atoms, which possess additional surface energy with enhanced electron enrichment for electrochemical activation of CO2 molecules. In the line of this we have synthesized non Nobel metal/metal oxide nanoparticles and decorated on graphene and g-carbon nitrite based hybrid electrocatalyst for electrochemical hydrogenation of CO2 to formate/formic acid. [4]

Furthermore reduction of formic acid to give methanol and finally methane as product which has widely used in petroleum industry as part of this formic acid important intermediate for came back again to fuel from CO2. Formic acid has natural antibacterial properties because of that used as antibacterial in food products as a preservative or on crops as a pesticide, production of leather, dyeing and finishing textiles, coagulant in many rubber manufacturing processes, it also helps tofermentation at a lower temperature,one of the basic raw materials of organic chemical and it has insect protective mechanisms. [5]

References

1.      J. Qiao, Y. Liu, F. Hong, J. Zhang, A review of catalysts for the electroreduction of carbon dioxide to produce low-carbon fuels,Chem. Soc. Rev. 43 (2014) 631-675.

2.      B. Khezri, A. C. Fisher, M. Pumera, CO2 reduction: the quest for electrocatalytic materials, J. Mater. Chem. A. 5 (2017) 8230-8246.

3.      W. Zhang, Y. Hu, L. Ma, G. Zhu, Y. Wang, X. Xue, R. Chen, S. Yang, Z. Jin, Progress and Perspective of Electrocatalytic CO2 Reduction for Renewable Carbonaceous Fuels and Chemicals,  Adv. Sci. 5 (2018) 1-25.

4.      Q. Han, N. Chen,  J. Zhanga, L. Qu, Graphene/graphitic carbon nitride hybrids for catalysis,

Mater. Horiz., 4 (2017) 832-850.

5.      D. Du, R. Lan, J. Humphreys, Progress in inorganic cathode catalysts for electrochemical conversion of carbon dioxide into formate or formic acid, J. Appl. Electrochem. 47 (2017) 661-678.