Design of blueberry anthocyanin/TiO(2) composite layer-based photoanode and N-doped porous blueberry-derived carbon-loaded Ni nanoparticle-based counter electrode for dye-sensitized solar cells

P25/PBP (TiO(2), anthocyanins) prepared by combining PBP (blueberry peels) with P25, and N-doped porous carbon-supported Ni nanoparticles (Ni@NPC-X) prepared using blueberry-derived carbon were used for the application as photoanode and the counter electrode, respectively, in dye-sensitized solar cells (DSSCs) to create a new perspective for blueberry-based photo-powered energy systems. PBP was introduced into the P25 photoanode and carbonized to form a C-like structure after annealing that improved its adsorption capacity for N719 dye, contributing a 17.3% higher power conversion efficiency (PCE) of P25/PBP-Pt (5.82%) than that of P25-Pt (4.96%). The structure of the porous carbon changes from a flat surface to a petal-like structure due to the N doping by melamine, and the specific surface area increases. N-doped three-dimensional porous carbon supported the loading and reduced the agglomeration of Ni nanoparticles, reducing the charge transfer resistance, and providing a fast electron transfer path. The doping of Ni and N on the porous carbon worked synergistically to enhance the electrocatalytic activity of the Ni@NPC-X electrode. The PCE of the DSSCs assembled by Ni@NPC-1.5 and P25/PBP was 4.86%. Also, the Ni@NPC-1.5 electrode exhibited 116.12 F g(−1) and a capacitance retention rate of 98.2% (10 000 cycles), further confirming good electrocatalysis and cycle stability.