Essential raw materials for photosynthesis are -
carbon dioxide: it is a gas which is released into atmosphere during respiration.
Water: it is another requirement for photosynthesis which is transported upward through xylem tissue to the leaves, from where it reaches photosynthetic cells.
Chlorophyll: it is green pigment in plants which act as catalyst. It is responsible for absorption of sun's light by the plant. The chlorophyll pigments are photoreceptor molecules which play a key role in the photosynthesis process.
Light: light effects photosynthesis with its intensity, duration and quality. In green light the rate of photosynthesis is minimum, while in red or blue light the rate of photosynthesis is maximum.
Hope this answer helps you!!