Abstract: As an abundant and low-cost natural resource, wood shows great potential in solar interfacial evaporation. Wood-based photothermal evaporators feature good hydrophilicity and excellent thermal insulation, yet their evaporation efficiency is relatively low, and research on relevant materials is still incomplete with preparation conditions needing further exploration. This work conducted lignin removal and surface carbonization with poplar wood as raw material, to obtain carbonized delignified poplar material (CDP). Xenon lamps simulated sunlight for photothermal experiments. The influences of delignification solution type, time, delignification time, carbonization temperature and carbonization layer height on photothermal evaporation are studied to determine the optimal preparation conditions. Results indicate that the optimal conditions are as follows: using NaClO₂ solution for delignification for 2 hours, carbonization under 400℃ with a carbonization layer height of 3.75 mm. Under 1.0 kW·m⁻² simulated sunlight, the material showed good evaporation performance with water evaporation rate reaching 1.78 kg·m⁻²·h⁻¹ and photothermal evaporation efficiency being 80.92%.