ZnO:Er, Li film prepared by sol–gel method and its properties of converting both UV and NIR light to visible light

•Li+ and Er3+ co-doped ZnO film was prepared by sol–gel method.•The obtained film can convert both UV and NIR light to visible light.•The film was featured with a high transmittance of 86.8% in 400–900 nm.

ZnO:Er, Li light conversion film has been successfully fabricated by sol–gel method. XRD measurement demonstrated the successful incorporation of Er3+ and Li+ into ZnO films. The as-grown film co-doped with 2% Er3+ and 3% Li+ is featured with a transmittance of about 86.8% in the range of 400–900 nm. Moreover, the film exhibits a visible light emission either being excited by 355 nm or 980 nm. Due to its relatively high transmittance characteristics and promising properties of converting both UV and NIR light to visible light, the developed film is considered to have a potential application in novel light conversion devices including solar cells.