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In this research,we reported the molecular-like Ag(ML-Ag)clusters and Eu3+ co-sensitized efficient broadband down-conversion luminescence in oxyfluoride glass,and the Ag nanocrystal enhanced up-conversion luminescence in the Er3+-yb3+codoped tellurite glass powder,respectively.The AgNO3/EuF3/YbF3 tri-doped oxyfluoride glass was prepared by a melting-quenching method,in which a high-efficient broadband down-conversion can be realized due to the simultaneous energy transfer processes of Eu3+→Yb3+,ML-Ag clusters→Yb3+,and ML-Ag clusters→Eu3+→Yb3+.The spectral measurements indicated that besides the F-center brought by the fluorides,the formation of the ML-Ag clusters and the evolution of silver species within the glass matrix were also closely related to the introduction of Eu3+ and Yb3+ ions.As the UV-visible irradiation in the wavelength region of 250-600 nm can be efficiently converted into near-infrared emission around 1000 nm in the AgNO3/EuF3/YbF3 tri-doped glass,which thus has promising application in enhancing the photovoltaic conversion efficiency of the silicon solar cell.By using the field-assisted diffusion method,the glass substrate containing Ag nanocrystals was prepared,and then the contribution of the obtained glass substrate after positive and reverse diffusion treatment on the up-conversion properties of the Er3+-yb3+codopedtellurite glass powder was investigated.The experimental results indicated that the reverse electric field-assisted diffusion process can greatly improve the up-conversion emission intensity.