Ionic liquid-assisted synthesis of highly branched Ag:AgCl hybrids and their photocatalytic activity

•Highly branched hybrid crystals of Ag and AgCl (Ag:AgCl) were synthesized using ionic liquid.•Octapod-shaped Ag:AgCl crystals were produced by rational control of ionic liquid.•The formation of Ag:AgCl octapods relies on the preferential overgrowth on {111} facets of cube seed particles.•The photocatalytic activity were studied upon visible light irradiation.•Ag:AgCl octapods show superior photocatalytic activity.