The invention discloses a nano colloidal motor and a preparation method thereof. The motor comprises an open spherical
platinum shell, wherein the
diameter of the shell is smaller than or equal to 500nm, the thickness of the shell is 5-30 nm, and the shell is coated with a silver shell or gold shell with thickness of 5-20 nm. The method comprises the following steps: firstly, placing a colloidalsphere on a substrate to form a single-layer close-packed
colloidal crystal template, and heating the
colloidal crystal template so as to obtain the single-layer close-packed
colloidal crystal template, wherein the colloidal sphere is fixedly connected with the substrate; and then carrying out
plasma etching on the single-layer close-packed colloidal
crystal template so as to obtain a single-layernon-close-packed colloidal
crystal template, wherein the colloidal sphere is fixedly connected with the substrate, then sequentially evaporating a
platinum layer and a silver layer (or a
gold layer)on the single-layer non-close-packed colloidal
crystal template, then separating the colloidal sphere sequentially coated with the
platinum layer and the silver layer (or the
gold layer) on the surface on the single-layer non-close-packed colloidal crystal template from the substrate by using a physical method, putting the mixture into a
solvent or subjecting the mixture to calcining to remove thecolloid ball to prepare a target product. The product is small in size, single in movement direction and hollow, and can be easily, widely and commercially applied to the technical fields of
drug targeting motion, material transportation,
ion detection,
sewage treatment and the like.