This study presents a method for synthesizing large-area monolayer MoS₂ films using chemical vapor deposition (CVD) on SiO₂/Si substrates. MoS₂, a transition metal dichalcogenide, has potential applications in catalysis, nanotribology, microelectronics, lithium batteries, hydrogen storage, medical, and optoelectronics. The synthesis involves the reaction of MoO₃ and sulfur powders at 650°C in a nitrogen atmosphere. The growth of MoS₂ is highly sensitive to substrate treatment, with the use of graphene-like molecules such as reduced graphene oxide (rGO), perylene-3,4,9,10-tetracarboxylic acid tetrapotassium salt (PTAS), and perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA) promoting the growth of MoS₂ layers. Large-area MoS₂ layers can be directly obtained on amorphous SiO₂ surfaces without the need for highly crystalline metal substrates or an ultrahigh vacuum environment. The synthesized MoS₂ films are highly crystalline and can be up to several millimeters in size. The MoS₂ layers are confirmed to be monolayer, bilayer, or few-layer through spectroscopic, microscopic, and electrical measurements. The MoS₂ films exhibit a monolayer structure with a thickness of approximately 0.72 nm. The study also shows that the MoS₂ layers can be used to fabricate bottom-gated transistors with a high on-off current ratio of approximately 1×10⁴ and a field-effect mobility of up to 0.02 cm²/(V·s). The growth of MoS₂ is initiated from center seeds, and the use of rGO treatment enhances the growth of MoS₂ layers. The study also demonstrates that both MoS₂ and WS₂ exhibit similar layer growth behavior on substrates pre-treated with graphene-like molecules. The results show that the MoS₂ films are highly crystalline and have good electrical performance, making them suitable for future electronic circuits requiring low standby power. The synthesis method is efficient and scalable, allowing for the production of large-area MoS₂ films with high quality and uniformity.This study presents a method for synthesizing large-area monolayer MoS₂ films using chemical vapor deposition (CVD) on SiO₂/Si substrates. MoS₂, a transition metal dichalcogenide, has potential applications in catalysis, nanotribology, microelectronics, lithium batteries, hydrogen storage, medical, and optoelectronics. The synthesis involves the reaction of MoO₃ and sulfur powders at 650°C in a nitrogen atmosphere. The growth of MoS₂ is highly sensitive to substrate treatment, with the use of graphene-like molecules such as reduced graphene oxide (rGO), perylene-3,4,9,10-tetracarboxylic acid tetrapotassium salt (PTAS), and perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA) promoting the growth of MoS₂ layers. Large-area MoS₂ layers can be directly obtained on amorphous SiO₂ surfaces without the need for highly crystalline metal substrates or an ultrahigh vacuum environment. The synthesized MoS₂ films are highly crystalline and can be up to several millimeters in size. The MoS₂ layers are confirmed to be monolayer, bilayer, or few-layer through spectroscopic, microscopic, and electrical measurements. The MoS₂ films exhibit a monolayer structure with a thickness of approximately 0.72 nm. The study also shows that the MoS₂ layers can be used to fabricate bottom-gated transistors with a high on-off current ratio of approximately 1×10⁴ and a field-effect mobility of up to 0.02 cm²/(V·s). The growth of MoS₂ is initiated from center seeds, and the use of rGO treatment enhances the growth of MoS₂ layers. The study also demonstrates that both MoS₂ and WS₂ exhibit similar layer growth behavior on substrates pre-treated with graphene-like molecules. The results show that the MoS₂ films are highly crystalline and have good electrical performance, making them suitable for future electronic circuits requiring low standby power. The synthesis method is efficient and scalable, allowing for the production of large-area MoS₂ films with high quality and uniformity.