The morphology is more spherical for H2-C-EN, H8-C-EN, and H9-C-EN due to using Euclea natalensis . However, among these three samples, H2-C-EN has the least spherical morphology. H9-C-EN exhibits the most spherical morphology, having been synthesized with a 1.5 mL/min drip rate from the phosphorus source, which facilitates the formation of its structure. Additionally, the synthesis temperature of 50 °C allows for the formation of larger particles compared to the H2-C sample, which reduces the tendency to form a rod-shaped morphology with increasing temperature . Some samples are covered by labyrinthine nanogrooves that could be induced using Euclea natalensis, similar to the hydroxyapatite nano-labyrinth .