Optical properties of 3d transition metal ion-doped sodium borosilicate glass

•3d transition metal ion (from Ti to Zn) doped SiO2Na2OB2O3 glasses.•Optical properties of doped glasses investigated.•V(IV,V); Cr(III, VI); Mn(II,III); Fe(II,III); Co(II); Ni(II); Cu(II) by XANES, DRS.•Strong visible absorption but only vanadium ion gives strong emission in glass.

SiO2Na2OB2O3 glasses doped with 3d-transition metal species from Ti to Zn were prepared by the melting-quenching technique and their optical properties were investigated. The X-ray absorption near edge spectra of V, Cr, and Mn-doped glasses indicate that the oxidation states of V(IV, V), Cr(III, VI) and Mn(II, III) exist in the studied glasses. The oxidation states revealed from the diffuse reflectance spectra of the glasses are V(IV, V), Cr(III, VI), Mn(III), Fe(II, III), Co(II), Ni(II), and Cu(II). Most of the 3d transition element ions exhibit strong absorption in the visible spectral region in the glass. Under ultraviolet excitation, the undoped sodium borosilicate glass produces weak and broad emission, while doping of vanadium introduces strong and broad emission due to the V(V) charge transfer transition. Only weak emission is observed from Ti(IV), Mn(II), Fe(III) and Cu(II), partly resulting from the strong electron–phonon coupling of the 3d-electrons and the relatively high phonon energy of the studied glass host, with the former leading to dominant nonradiative relaxation based on multiphonon processes for most of the 3d excited states.

Graphical abstractPhotographs of undoped (SiO2)50 (Na2O)25 (B2O3)25 (SiNaB) glass and transition metal ion-doped (TM)0.5 (SiO2)49.5 (Na2O)25 (B2O3)25 glass samples.Figure optionsDownload full-size imageDownload as PowerPoint slide