Effect of SnO ₂ on Structure and Properties of the Low‐Melting V ₂ O ₅ ‐TeO ₂ ‐CuO Glass for Vacuum Glazing Sealing

ABSTRACT Low‐melting sealing glass plays a crucial role in various applications. This study investigates the effect of SnO 2 addition on the structure and properties of the V 2 O 5 ‐TeO 2 ‐CuO low‐melting sealing glass. Six glasses (S1–S6) were prepared with nominal SnO 2 additions of 0, 5, 10, 15, 20, and 25 mol per 100 mol base glass. ICP‐OES analysis revealed that the SnO 2 contents increased with nominal addition, while showing measurable differences from the nominal batch compositions. The structural evolution of these sealing glasses was investigated by Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy (Raman), and X‐ray photoelectron spectroscopy (XPS) analyses. It was demonstrated that [VO 5 ] and [TeO 3 ] structural units were transformed into [VO 4 ] and [TeO 4 ] configurations with the progressive addition of SnO 2 . The thermal expansion coefficient (CTE) of the sealing glasses was reduced from 105 × 10 −7 /°C to 86.4 × 10 −7 /°C, thereby improving the compatibility with the glass substrate (92 × 10 −7 /°C). Based on the flowability tests, S3 was identified as the optimal composition, with desirable fluidity achieved at 380°C. When sealing was performed at this temperature, the highest shear strength of 3.43 MPa was obtained. These findings provide valuable insights into the rational design of advanced low‐melting sealing glass.