Infrared-to-visible upconversion emission of Er3+/Yb3+-codoped SrMoO4 phosphors as wide-range temperature sensor

• Er3+/Yb3+-codoped SrMoO4 phosphors exhibited strong upconversion emissions.
• Temperature sensing properties of SrMoO4:0.01Er3+/0.05Yb3+ phosphor were investigated.
• The obtained samples can be operated in a very wide temperature range of 93–773 K.
• The maximum sensitivity of SrMoO4:0.01Er3+/0.05Yb3+ phosphor was as high as 0.0128 K−1.
• Er3+/Yb3+-codoped SrMoO4 phosphors can be used in low- and high-temperature thermometry.

Er3+/Yb3+-codoped SrMoO4 phosphors were prepared by a high-temperature solid-state reaction method. At room temperature, all the as-prepared samples exhibited strong upconversion properties and the emission intensity increased dramatically with the increase of Yb3+ ion concentration, reaching its maximum value when the concentration was 5 mol%. The dependence of emission intensity on the pump power suggested that the upconversion emission was a two-photon process. Furthermore, the optical temperature sensing properties based on green upconversion emissions of the SrMoO4:0.01Er3+/0.05Yb3+ phosphor were studied. It is found that the SrMoO4:0.01Er3+/0.05Yb3+ phosphor can be operated over a very wide temperature range of 93–773 K with a maximum sensitivity of ∼0.0128 K−1, indicating that low- and high-temperature thermometry can be simultaneously realized in this phosphor.