This present disclosure relates to the use of Avobenzone-defect rich ZnO nanocrystals complex as multifunctional active ingredient in sunscreen, cosmetic and dermatological compositions, and more particularly to photostable sunscreen compositions and their use in improving the UV protection, aesthetic and natural appearance of the biological surface. The complex Av-DZnONCs shows improved photostability and extended UVA filtering as opposed to sunscreen formulations containing only ZnO or Avobenzone.