The DSSCs that coupled the nanoparticle bottom layer (13 m) and the layer of large porous spheres (8 m) show 6.39% power efficiency. Further increase of nanoparticle layer thickness and the large pore sphere layer thick-ness leaded to obvious decrease of power efficiency. Fig. 6(A) shows the J–V dependences of DSSCs (see the explanation in Table 3).
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