To meet the energy demands artificial photosynthesis is playing the most promising role these days. Using sunlight directly in a manner that can provide useful chemicals is a sustainable means of generating energy. Studies are going on in this context to make better and effective photocatalyst. In this paper, we study the synthesis of flower‐like graphene quantum dots‐based fuschin (GQDF) photocatalyst from lemon, which is created by a green and sustainable process that is effective and environment friendly. The UV‐visible spectra of prepared GQDF showed a high molar extinction coefficient. A flower‐like GQDF photocatalyst has better catalytic efficiency for the selective creation and regeneration of the NAD(P)H cofactor. A newly designed flower‐like GQDF photocatalyst is used as one of its most effective photocatalysts as they have several additional applications in the removal of CO2 and aqueous contaminants like heavy metals.