## 1 Introduction  
In the last few decades, one of the critical primary issues that has remained a significant challenge is climate change. The use of fossil fuels in an excessive way leads to the increased production of greenhouse gasses (mainly CO2) that contribute to climate change. It is eminent that reducing CO2 coming from human activities is one of the most important factors that might contribute to decreasing this effect [1]. CO2 can be selectively captured at emission points (industries) and afterward either stored (Carbon Capture and Storage (CCS)) or reutilized as a raw material. The main approaches for reversible capture can be categorized as (1) the use of liquid adsorbents and (2) the use of solid adsorbents [2]. The reutilization of CO2 in a more useful raw material or for energy has been gaining ground in the last few decades. CO2 can be reduced with photocatalysis to CH3 OH, CH4 and CO [1, 3]. Even though other methods for conversion have been explored, the photocatalytic one is considered a promising one [4]. Other studies show that CO2 can also be used for the production of chemicals such as urea,ethylene carbonate, salicylic acid [5], carbonic acid diesters (contributing to the substitute for phosgene) [6], formic acid, formaldehyde, higher hydrocarbons and oxygenates [7]. Current technologies for CO\({}_{2}\) are based on capturing CO\({}_{2}\) from largely exhausted flue gasses by employing amine-based regenerative chemical absorption using aqueous amines. This process has high efficiency for CO\({}_{2}\) capture. However, it is energy-intensive, complex and requires a high-energy input for regenerating and handling the corrosive solvents resulting from amine-based solutions' oxidation. This separation technique utilizes certain temperatures. One of the challenges for the solvent-based system is to decrease its energy consumption for solvent heating. Thus, solid adsorbents appeared to be promising candidates. Solid adsorbents have a smaller specific heat capacity than liquid solvents, which can decrease the heat requirements and energy consumption for CO\({}_{2}\) capture. Toward this direction, research in various porous materials with fine structural and chemical properties has been widely investigated. Some currently proposed materials are zeolites, activated carbon, amine-modified silica materials and metal organic frameworks [8]. Adsorbents such as zeolites and amine-modified mesoporous materials may not be the most suitable materials for capturing high concentrations of CO\({}_{2}\) under high-pressure conditions [8,9]. All the previous materials are currently in use or under investigation for CO\({}_{2}\) adsorption and photocatalysis. The development of stable, highly efficient and low-cost photocatalysts, especially for visible light application, is significant in bringing this technique to the market [4]. What is considered a good solution for catalytic reactions with a wide range of applications in catalysis is rare earth oxides. These oxides have unique catalytic and optical properties. Stable and nontoxic cerium oxide (CeO\({}_{2}\)) has been widely used as a photoactive material in solar cells and as a photocatalyst [1]. Cerium is the most abundant rare earth element (0.0046 wt% in the Earth's crust) as a metal that has low toxicity, excellent chemical stability and a high surface-to-volume ratio. Moreover, it is used in many fields such as low-temperature oxidation, absorption, alcohol-to-oxygen conversion, solid fuel cells and wastewater treatment [4]. Furthermore, photocatalytic activity can be synergistically enhanced by doping cerium, as the redox couple Ce\({}^{3+}\)/Ce\({}^{4+}\) can be transferred between Ce\({}_{2}\)O\({}_{3}\) and CeO\({}_{2}\) through either oxidation or reduction [4,10]. CeO\({}_{2}\) is a material that can be used in various catalytic reactions [3]. One of its most important advantages is the rich oxygen vacancies that have been proven to display the superior photocatalytic activity used in the energy and environmental fields [3,4,11].