## 1 Introduction  
Biomass was essential to mankind for a long time to produce heat energy before the rise of fossil fuels [1]. Today, modern technologies are relying on fossil fuels to produce of energy. The burning of either fossil fuels or biomass produces an enormous amount of carbon dioxide (CO\({}_{2}\)), which causes global warming [2]. CO\({}_{2}\) is a major greenhouse gas that is considered to contribute a large portion of overall greenhouse gas (GHG) emissions throughout the world. Recently, the rate of greenhouse gases emission has been reaching the value of 6% per annum, and a major portion of greenhouse gases consists of carbon dioxide [3]. Biomass is a major renewable carbon-based energy resource that is readily available to fulfill the essential requirements of human beings; for carbon-based chemical production, it is the best alternative to fossil fuels. Until now, biomass has been utilized to produce heat energy or power generation in industries, but it can also be utilized to obtain valuable fuels, chemicals, materials, and other products, and this will also contribute to alleviating the emissions of carbon dioxide [4]. For the production of numerous materials and feedstocks, many biomass-derived chemicals to facilitate the green processing of biomass are readily available [5]. Different types of biomass are produced in a country, such as harvests waste, food processing trash, municipal garbage, animal waste, etc. [6]. Presently, certain technologies can convert biomass to valuable products. Liquid, gaseous, and solid fuels can be produced by the thermochemical conversion of biomass through different methods such pyrolysis [7], gasification [8], combustion, and liquification [9]. The main products produced by the thermochemical conversion of biomass are bio-oil, methanol, aerosols, syngas, methane gas, hydrogen fuel, etc. Biomass can also be biologically converted into liquid fuels such as ethanol, dimethyl ether, and biogas by digestion and fermentation [10]. The conversion of biomass through thermochemical (combustion, pyrolysis, gasification, and liquification) and biological (digestion and fermentation) methods also produces a large amount of carbon dioxide [11]. Amongst various approaches, recently, photocatalysis has demonstrated to be an alluring approach for the conversion of biomass into useful and valuable chemicals/fuels, without polluting the environment. Photocatalysis is a process in which photons (solar irradiations) re used to accelerate chemical reactions in the presence of a suitable photocatalyst [12]. Photocatalysis is portrayed as a unique process to deal with the environmental crisis and energy rectification to preserve a good quality of life and avoid acute and chronic damages caused by CO\({}_{2}\) emission. Photocatalysis is the most versatile and effective of emerging processes for the conversion of biomass [12]. The objective of the present experimental work was to catalytically convert biomass into useful/valuable products and avoid the direct combustion of biomass--so to keep the atmosphere as clean as possible--using a visible-light-active photocatalyst. For the conversion of biomass, TiO\({}_{2}\) is most commonly used as a photocatalyst due to its valuable properties. In fact, TiO\({}_{2}\) is abundant, has a favorable surface area, is nontoxic, is chemically and biologically inert and cost-effective, and has a high stability under sunlight irradiation [13; 14]. However, despite certain benefits, TiO\({}_{2}\) possesses a major limitation consisting in its wide band gap pf 3.2-3.4 eV, not favorable for efficient catalysis, because of the absorption of ultraviolet radiations comprising only 4% of the solar spectrum [14]. Such specific drawback has led to its replacement by visible-light-active photocatalysts capturing a major portion of light and hence promoting reaction efficiency. Until today, various visible-light-active photocatalysts have been developed with the aim of better performance.