The structure of electronic energy bands, electric charge distribution and the amount of charge transfer of molecular crystals 1-MCI·(TCNQ)_2 (Ⅰ) and 2-MCI· (TCNQ)_2 (Ⅱ) have been studied. The results are...The structure of electronic energy bands, electric charge distribution and the amount of charge transfer of molecular crystals 1-MCI·(TCNQ)_2 (Ⅰ) and 2-MCI· (TCNQ)_2 (Ⅱ) have been studied. The results are: (ⅰ) The dominant contributions to the electrical conductivities for crystals Ⅰ and Ⅱ are from TCNQ molecular columns, and the charge carriers are electrons. (ⅱ) The electrical conduction is mainly due to the hopping of charge carriers between the seats of lattice. (ⅲ) The considerable difference of the electrical conductivities between crystals Ⅰ and Ⅱ is due to the differences between (a) the concentrations of charge carriers n_(AⅠ)~C= 0.9988-|e|/cell and n_(AⅡ)~C=0.0340-|e|/cell; (b) the widths of the energy bands △E_(AⅠ)^(LU)=0.88 eV and △E_(AⅡ)~LU=0.040 eV; (c) the first derivative of E with respect to k, (dE/dk)_(K_FAⅠ)^(LU)=0.27 eV· and (dE/dk)_(K_FAⅡ)~LU=0.0048 eV·; and (d) the difference of energy barriers for the hopping of charge carriers ∈_Ⅱ-∈Ⅰ=2.5-8.8 kJ/mol.展开更多
Design and development of high-efficiency and durable oxygen evolution reaction(OER)electrocatalysts is crucial for hydrogen production from seawater splitting.Herein,we report the in situ electrochemical conversion o...Design and development of high-efficiency and durable oxygen evolution reaction(OER)electrocatalysts is crucial for hydrogen production from seawater splitting.Herein,we report the in situ electrochemical conversion of a nanoarray of Ni(TCNQ)2(TCNQ=tetracyanoquinodimethane)on graphite paper into Ni(OH)_(2) nanoparticles confined in a conductive TCNQ nanoarray(Ni(OH)_(2)-TCNQ/GP)by anode oxidation.The Ni(OH)_(2)-TCNQ/GP exhibits high OER performance and demands overpotentials of 340 and 382 mV to deliver 100 mA·cm^(−2) in alkaline freshwater and alkaline seawater,respectively.Meanwhile,the Ni(OH)_(2)-TCNQ/GP also demonstrates steady long-term electrochemical durability for at least 80 h under alkaline seawater.展开更多
基金Project supported by the National Natural Science Foundation of China.
文摘The structure of electronic energy bands, electric charge distribution and the amount of charge transfer of molecular crystals 1-MCI·(TCNQ)_2 (Ⅰ) and 2-MCI· (TCNQ)_2 (Ⅱ) have been studied. The results are: (ⅰ) The dominant contributions to the electrical conductivities for crystals Ⅰ and Ⅱ are from TCNQ molecular columns, and the charge carriers are electrons. (ⅱ) The electrical conduction is mainly due to the hopping of charge carriers between the seats of lattice. (ⅲ) The considerable difference of the electrical conductivities between crystals Ⅰ and Ⅱ is due to the differences between (a) the concentrations of charge carriers n_(AⅠ)~C= 0.9988-|e|/cell and n_(AⅡ)~C=0.0340-|e|/cell; (b) the widths of the energy bands △E_(AⅠ)^(LU)=0.88 eV and △E_(AⅡ)~LU=0.040 eV; (c) the first derivative of E with respect to k, (dE/dk)_(K_FAⅠ)^(LU)=0.27 eV· and (dE/dk)_(K_FAⅡ)~LU=0.0048 eV·; and (d) the difference of energy barriers for the hopping of charge carriers ∈_Ⅱ-∈Ⅰ=2.5-8.8 kJ/mol.
基金supported by the National Natural Science Foundation of China(No.22072015)the Opening Fund of Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research(Hunan Normal University)Ministry of Education(2020-02).
文摘Design and development of high-efficiency and durable oxygen evolution reaction(OER)electrocatalysts is crucial for hydrogen production from seawater splitting.Herein,we report the in situ electrochemical conversion of a nanoarray of Ni(TCNQ)2(TCNQ=tetracyanoquinodimethane)on graphite paper into Ni(OH)_(2) nanoparticles confined in a conductive TCNQ nanoarray(Ni(OH)_(2)-TCNQ/GP)by anode oxidation.The Ni(OH)_(2)-TCNQ/GP exhibits high OER performance and demands overpotentials of 340 and 382 mV to deliver 100 mA·cm^(−2) in alkaline freshwater and alkaline seawater,respectively.Meanwhile,the Ni(OH)_(2)-TCNQ/GP also demonstrates steady long-term electrochemical durability for at least 80 h under alkaline seawater.
