The goal of this work is aimed to improve the power conversion efficiency of single crystalline silicon-based photovoltaic (PV) cells by using the solar spectral conversion principle,which employed a down-converting phosphor to convert a high-energy ultraviolet photon to the less energetic red-emitting photons to improve the spectral response of Si solar cells.In this study,the surface of silicon solar cells was coated with a red-emitting KCaGd(PO4)2∶Eu3+ phosphor by using the screen-printing technique.In addition to the investigation on the microstructure using scanning electron microscopy (SEM),we measured the short circuit current (Isc),open circuit voltage (Voc),and power conversion efficiency (η) of spectral-conversion cells and compared with those of bare solar cells as a reference.Preliminary experimental results revealed that in an optimized PV cell,an enhancement of (0.64+0.01)％ (from 16.03％ to 16.67％) in △η ofa Si-based PV cell was achieved.