CHAPTER 13: A Comparative Study of 0D, 1D, and 2D Nanocatalysts Towards CO₂ Conversion

In the twentyfirst century global energy crises have opened up research into alternative energy sources, among which electrochemical CO₂ conversion into chemicals and fuels like methanol, ethanol, methane, etc., using semiconductor nano dimensional metal oxides is accepted as a valid method. Photocatalytic reduction of CO₂ into solar fuels is also recognized as an attractive approach to solving the environmental and energy crises. In this field, 2D transition metal oxides have attracted significant attention in CO₂ conversion into chemicals and fuels owing to their remarkable properties. In this chapter, a comparative study of 0D, 1D, and 2D nanocatalysts towards CO₂ conversion and improvement of the electrochemical CO₂ conversion system's efficiency is demonstrated. Detailed designs of various dimensional nanocomposite systems and their functional criteria, as well as electrical and mechanical properties which act as electrochemical catalysts for CO₂ conversion into chemicals and fuels, are described thoroughly. The unique mechanical, electrical, surface charge density, and optical properties of nanomaterials make it possible to create heterojunction photocatalyst with complex structures of energy zones, permitting a wide range of visible light spectra and showing the positive effects on the absorption of visible light. This chapter also highlights the mechanism of photoelectrochemical CO₂ conversion into chemicals and fuels and the enhancement of the yield of the CO₂ converted high value-added products with various 0D, 1D, and 2D nanostructured materials. In brief, this chapter deals with a comparative study rationally designing and synthesizing nano-dimensional metal oxide photocatalysts toward high‐efficiency photoreduction of CO₂.