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With K + as charge compensator, a series of KSr 4 (BO 3 ) 3 :Dy 3+ , Tb 3+ phosphors were successfully synthesized by solid–state reaction process. Under near-ultraviolet excitation (389 nm), the green emission of Tb 3+ is observed in Dy 3+ /Tb 3+ codoped samples due to the efficient energy transfer from Dy 3+ to Tb 3+ . The energy transfer efficiency, average donor-acceptor distance, as well as transfer mechanism were also studied. The energy transfer efficiency of KSr 4 (BO 3 ) 3 :Dy 3+ , xTb 3+ increased gradually and reached about 60% when the concentration of Tb 3+ was 0.030. And the critical distance R Dy-Tb was calculated to be 15.36 Å. Moreover, the energy transfer mechanism from Dy 3+ to Tb 3+ in KSr 4 (BO 3 ) 3 host was demonstrated to be dipole–dipole interaction. In addition, the emitting colors of Dy 3+ /Tb 3+ codoped samples can be adjusted from the edge of white area to green via tuning the Tb 3+ doped concentration. [ABSTRACT FROM AUTHOR]

N-doped carbon supported MOFs derived P-doped ZnCo 2 O 4 nanosheets (ZCP/NC) with rich oxygen vacancy are rationally designed and synthesized via a chemical heat treatment strategy. In the unique structure, N-doped carbon as a skeleton can provide an electrically conductive 3D continuous network with large surface area for the growth of active materials. P-doped ZnCo 2 O 4 nanosheets are rich in oxygen vacancies and have a large exposure area, which can enhance the charge storage capabilities. Electrochemical measurement displayed that the novel electrodes can deliver a highest specific capacitance of 1581.5 F g−1 at 1 A g−1. An asymmetric supercapacitor (ASC) fabricated by ZCP/NC and activated carbon can reach a high energy density of 47.8 Wh kg−1 at power density of 800 W kg−1. Besides, The ASC also exhibits a cyclic retention of 90.6% for 5000 cycles. The reasons for excellent properties of ZCP/NC are discussed in detail. ga1 3D N-doped carbon supported MOFs derived P-doped ZnCo 2 O 4 nanosheets with rich oxygen vacancies showed a superior electrochemical performance. • 3D N-doped carbon supported MOFs derived P-doped ZnCo 2 O 4 nanosheets are successfully prepared. • P-doped ZnCo 2 O 4 nanosheets are rich in oxygen vacancies can enhance the charge storage capabilities. • The unique electrode displays a high capacitance of 1581.5 F g−1. • The hybrid supercapacitor achieves a high energy density of 47.8 Wh L−1. [ABSTRACT FROM AUTHOR]