Surface modifications of photoanodes in dye sensitized solar cells: enhanced light harvesting and reduced recombination

摘要: In a quest to harvest solar power, dye-sensitized cells (DSSCs) have potential for low-cost eco-friendly photovoltaic devices. The major processes which govern the efficiency of DSSC are photoelectron generation, injection photo-generated electrons conduction band (CB) mesoporous nanocrystalline semiconductor (nc-SC); transport CB through nc-SC and subsequent collection at counter electrode (CE) external circuit; dye regeneration by redox couple or hole layer (HTL). Most these occur various interfaces photoanode. addition, recombination losses with either molecules take place interfaces. Therefore, one key requirements high is improve light harvesting photoanode reduce this direction, surface modification simplest method among other approaches available in literature. review, we present comprehensive discussion on photoanode, has been adopted literature not only enhancing but also reducing recombination. Various towards discussed (i) fluorine-doped tin oxide (FTO)/nc-SC interface modified via compact material blocks exposed sites FTO electrolyte (or HTL), (ii) nc-SC/dye acid treatment resulting enhanced loading due positively charged depositing insulating/semiconducting blocking surface, acts as tunneling barrier recombination, (iii) employing co-adsorbents helps aggregation thereby (iv) dye/electrolyte dye/HTL) using additives provides passivation well positive movement Fermi level owing negative charge hence improves reduced Finally, discuss advantages disadvantages high-efficiency DSSCs.