Ca2Al2SiO7:Bi3+, Eu3+, Tb3+: A potential single-phased tunable-color-emitting phosphor

► Energy transfer from Bi3+ to Eu3+ was investigated. ► Color tunable from Bi3+ to Eu3+ can be achieved by Bi3+, Eu3+-codoped Ca2Al2SiO7. ► White light can be realized in Ca2Al2SiO7:Bi3+, Eu3+, Tb3+ phosphor.