the tandem photovoltaic device further comprises at least one of a second light-trapping structure located on a side of a shading surface of the bottom cell and a third light-trapping structure located on a side of a phototropic surface of the top cell;

the first light-trapping structure, the second light-trapping structure, and the third light-trapping structure are respectively selected from any one of metal or semiconductor material, and localized surface plasmons generated by the first light-trapping structure, the second light-trapping structure, and the third light-trapping structure respectively correspond to different peaks of light-wave response;

the tandem photovoltaic device has a first cross section perpendicular to a phototropic surface of the tandem photovoltaic device, the first light-trapping structure, the second light-trapping structure, and the third light-trapping structure form discrete microstructures on the first cross section, average sizes of projections of the discrete microstructures on the phototropic surface of the tandem photovoltaic device are respectively d1, d2 and d3, and average distances between adjacent discrete microstructures thereof are respectively w1, w2 and w3; and

at least one first cross section presents, such that the average sizes of projections of the discrete microstructures on the phototropic surface of the tandem photovoltaic device and the average distances between the adjacent discrete microstructures have following relationships: