A selective ‘turn-on’ fluorescent chemosensor for detection of Al3+ in aqueous medium: Experimental and theoretical studies

•A Schiff base chemosensor, HL, give cyan fluorescent response upon binding Al3+.•The chemosensor show good selectivity to Al3+ compared other competing metal ions.•The compound binds Al3+ in 2:1 ratio with a binding constant of 2.1 × 104 M−1.•Limit of detection of HL for Al3+ is found to be as low as 4.32 × 10−6 M.•The probe serves as an efficient fluorescent sensor at pH range 4.