Highly Ecofriendly Inorganic Pesticide Based on TiO2 Incorporated with Nano-Carbon Composites for Phytophthora palmivora Fungus Disinfection

Crop destruction organisms are an essential factor hindering cocoa plants' production yield. It is the biggest problem for cocoa farmers to resolve and reduce the impact of the P. palmivora fungus on cocoa pods. Herein, this study presents the optimization of inorganic pesticides based on nano-carbon self-doped TiO 2 (C/TiO 2 ) nanocomposites capable of disinfecting broad-spectrum P. palmivora microorganisms for the practical application of photodisinfection technology. C/TiO 2 nanocomposite-based inorganic pesticide has been prepared by sol–gel method to produce nanospray and planted in media containing P. palmivora fungus. To identify the various composition of the C/TiO 2 nanospray, they were evaluated by FTIR spectroscopy to observe the functional groups of the nano-carbon and TiO 2 , which clearly contained –OH (3446–3448 cm −1 ), C≡C (2366–2370 cm −1 ), C=O (1797–1799 cm −1 ), C–H (1425 cm −1 ), C–O (1163–1203 cm −1 ), C–H (875–877 cm −1 ), and Ti–O (875–877 cm −1 ) groups. Some researchers have reported that nano-carbon significantly changes the band gap energy of TiO 2 under visible light and can also be active under dark conditions. This statement is relevant to our experimental results that 0.3% C/TiO 2 nanocomposites can inhibit the fungus P. palmivora with a percentage inhibition value of 72.7%. However, the high-performance efficiency proved strong when subjected to visible light irradiation with an inhibition value of 98.6%. Our results indicate that C/TiO 2 nanocomposites have great potential in agricultural plant pathogen disinfection.