Preparation And Photovoltaic Performance Of Photoelectrical Films With Broad Spectral Response

In recent years,as the crystal silicon and organic compound thin-film solar cells still suffer the disadvantages of high cost and pollution,the research on low-cost,long-term,high-performance,and eco-friendly 3rd-generation solar cells is in great boom.One crucial issue is that,the performance of 3rd-generation of solar cells is generally limited by the narrow response spectra of their photoelectric films.Therefore,it is significant to develop photoelectric film with broad spectral response for further photovoltaic-performance improvement.In this context,this thesis launches a series of study around the topic of "the research on preparation and photovoltaic performance of photoelectrical films with broad spectral response".The detailed progress is as follows:1.A plasmon-enhanced upconversion composite Y2O3:Er/Au@TiO2(SYE/A@T)with a three-dimensional starlike morphology was prepared and then mixed with submicron TiO2(200 nm)to form a multifunctional scattering layer in TiO2-based dye-sensitized solar cells(DSSCs).In such starlike micronsized upconverter,Au nanoparticle-assisted plasmon effect could intensify the upconversion emission of Y2O3:Er,and silmutaneously TiO2 coating could improve the charge transport within SYE/A@T.Therefore,the SYE/A@T showed broadened light-absorbing region to near-infrared region and improved light-scattering ability,leading to an improved photovoltaic performance of DSSCs.With the optimum mixing ratio,a PCE of 8.62%was attained,which was a significant improvement of 27.6%compared with the cell without adding SYE/A@T.2.A super flat perovskite film was prepared via spin-coating of a DMF/DMSO solution of CH3NH3PbI3 followed by dripping the designed hybrid rinse solvent(n-hexane and chlorobenzene)for planar perovskite solar cells.The hybrid rinse solvent induced to form a well-defined DMSO-PbI2-MAI intermediate phase,and hence improved the flatness of perovskite film with a roughness of 7.3 nm.Microstructure,TR-PL,EIS,and IMPS characterizations show that the superflat perovskite film allowed tight contact and facile interfacial charge transfer at ZnO/CH3NH3PbI3/spiro-OMeTAD interfaces.Such a hybrid rinse solvent processing perovskite film achieved a highly reproducible photovoltaic performance in PHJ-PSCs with an average PCE of 16.36%and a champion of 16.93%.3.A(3-NaYF4:Yb,Er upconversion nanocrystals(UCNCs)-embedded CH3NH3PbI3 perovskite composite film was firstly prepared.Specifically,the CH3NH3I-capped ?-NaYF4:Yb,Er UCNCs,which were resulted from ligand-exchange treatment,was added into the perovskite precursor and then served as nucleation sites to induce heteroepitaxial growth of perovskite crystals during the spin-coating process,simultaneously being in situ embedded into the perovskite film.The resulting UCNCs-embedded perovskite composite film not only exhibited a uniform pinhole-free morphology with enlarged crystal grains,but also enabled NIR absorption via upconversion effect.The PHJ-PSC device fabricated using the UCNCs-embedded perovskite film achieved a champion PCE of 19.70%under AM 1.5G and 0.37%under 980 laser irradiation,respectively corresponding to a 46%and a 740-fold increase from that of its counterpart without UCNCs.Importantly,the final PCE of the UCNCs-embedded cell still remained the 81%of the highest value after air-ambient exposure for 33 days,exhibiting good air-ambient durability.