Herein, novel plasmonic Bi metal in situ deposited in reduced Ti O2 microspheres(Bi@R-Ti O2) are fabricated via a bimetallic MOF-derived synthesized strategy by adjusting the synthesizing temperature. Different charac...Herein, novel plasmonic Bi metal in situ deposited in reduced Ti O2 microspheres(Bi@R-Ti O2) are fabricated via a bimetallic MOF-derived synthesized strategy by adjusting the synthesizing temperature. Different characterization techniques, including XRD, SEM, TEM, XPS, DRS, PL, EIS, and photocurrent generation, are performed to investigate the structural and optical properties of the as-prepared samples. The results indicate that the Bi particles are generated inside and outside of reduced Ti O2 microspheres via the reduction of Ti4+ and Bi3+ by ethylene glycol. When the annealing temperature is controlled at 300 o C, the corresponding Bi@R-Ti O2-300 sample with an appropriate amount of Bi nanoparticles exhibits the highest full solar spectrum photocatalytic oxygen evolution activity(4728.709 μmol h–1 g–1), which is 5.9 and 9.5 times higher than that of pure Ti O2 and Bi-Ti bimetal organic frameworks(Bi-Ti-MOFs). Several reasons are suggested for the above results:(1) Bi metal behaves as an "electron acceptor" to accelerate the charge carrier transfer from Ti O2 to Bi;(2) The surface plasmon resonance effect of loaded metallic Bi particles can enhance the visible and NIR light absorption capacity;(3) The generation of Ti3+ further narrows the band gap of TiO2.展开更多
Circuits with switched current are described by an admittance matrix and seeking current transfers then means calculating the ratio of algebraic supplements of this matrix. As there are also graph methods of circuit a...Circuits with switched current are described by an admittance matrix and seeking current transfers then means calculating the ratio of algebraic supplements of this matrix. As there are also graph methods of circuit analysis in addition to algebraic methods, it is clearly possible in theory to carry out an analysis of the whole switched circuit in two-phase switching exclusively by the graph method as well. For this purpose it is possible to plot a Mason graph of a circuit, use transformation graphs to reduce Mason graphs for all the four phases of switching, and then plot a summary graph from the transformed graphs obtained this way. First the author draws nodes and possible branches, obtained by transformation graphs for transfers of EE (even-even) and OO (odd-odd) phases. In the next step, branches obtained by transformation graphs for EO and OE phase are drawn between these nodes, while their resulting transfer is 1 multiplied by z^1/2. This summary graph is extended by two branches from input node and to output node, the extended graph can then be interpreted by the Mason's relation to provide transparent current transfers. Therefore it is not necessary to compose a sum admittance matrix and to express this consequently in numbers, and so it is possible to reach the final result in a graphical way.展开更多
Transition metal nitrides (TMNs) are of particular interest by virtue of their synergic advantages of superior electrical conductivity, excellent environmental durability and high reaction selectivity, yet it is dif...Transition metal nitrides (TMNs) are of particular interest by virtue of their synergic advantages of superior electrical conductivity, excellent environmental durability and high reaction selectivity, yet it is difficult to achieve flexible design and operation. Herein, mesocrystal nanosheets (MCNSs) of vanadium nitride (VN) are synthesized via a confined-growth route from thermally stable layered vanadium bronze, representing the first two-dimensional (2D) metallic mesocrystal in inorganic compounds. Benefiting from their single-crystalline-like long-range electronic connectivity, VN MCNSs deliver an electrical conductivity of 1.44×10^5 S/m at room temperature, among the highest values observed for 2D nanosheets. Coupled with their unique pseudocapacitance, VN MCNS-based flexible supercapacitors afford a superior volumetric capacitance of 1,937 mF/cm3. Nitride MCNSs should have wide applications in the energy storage and conversion fields because their intrinsic high conductivity is coupled with the reactivity of inorganic lattices.展开更多
基金the National Natural Science Foundation of China(51872173 and 51772176)Taishan Scholarship of Young Scholars(tsqn201812068)+2 种基金Natural Science Foundation of Shandong Province(ZR2017JL020)Taishan Scholarship of Climbing Plan(tspd20161006)Key Research and Development Program of Shandong Province(2018GGX102028)~~
文摘Herein, novel plasmonic Bi metal in situ deposited in reduced Ti O2 microspheres(Bi@R-Ti O2) are fabricated via a bimetallic MOF-derived synthesized strategy by adjusting the synthesizing temperature. Different characterization techniques, including XRD, SEM, TEM, XPS, DRS, PL, EIS, and photocurrent generation, are performed to investigate the structural and optical properties of the as-prepared samples. The results indicate that the Bi particles are generated inside and outside of reduced Ti O2 microspheres via the reduction of Ti4+ and Bi3+ by ethylene glycol. When the annealing temperature is controlled at 300 o C, the corresponding Bi@R-Ti O2-300 sample with an appropriate amount of Bi nanoparticles exhibits the highest full solar spectrum photocatalytic oxygen evolution activity(4728.709 μmol h–1 g–1), which is 5.9 and 9.5 times higher than that of pure Ti O2 and Bi-Ti bimetal organic frameworks(Bi-Ti-MOFs). Several reasons are suggested for the above results:(1) Bi metal behaves as an "electron acceptor" to accelerate the charge carrier transfer from Ti O2 to Bi;(2) The surface plasmon resonance effect of loaded metallic Bi particles can enhance the visible and NIR light absorption capacity;(3) The generation of Ti3+ further narrows the band gap of TiO2.
文摘Circuits with switched current are described by an admittance matrix and seeking current transfers then means calculating the ratio of algebraic supplements of this matrix. As there are also graph methods of circuit analysis in addition to algebraic methods, it is clearly possible in theory to carry out an analysis of the whole switched circuit in two-phase switching exclusively by the graph method as well. For this purpose it is possible to plot a Mason graph of a circuit, use transformation graphs to reduce Mason graphs for all the four phases of switching, and then plot a summary graph from the transformed graphs obtained this way. First the author draws nodes and possible branches, obtained by transformation graphs for transfers of EE (even-even) and OO (odd-odd) phases. In the next step, branches obtained by transformation graphs for EO and OE phase are drawn between these nodes, while their resulting transfer is 1 multiplied by z^1/2. This summary graph is extended by two branches from input node and to output node, the extended graph can then be interpreted by the Mason's relation to provide transparent current transfers. Therefore it is not necessary to compose a sum admittance matrix and to express this consequently in numbers, and so it is possible to reach the final result in a graphical way.
文摘Transition metal nitrides (TMNs) are of particular interest by virtue of their synergic advantages of superior electrical conductivity, excellent environmental durability and high reaction selectivity, yet it is difficult to achieve flexible design and operation. Herein, mesocrystal nanosheets (MCNSs) of vanadium nitride (VN) are synthesized via a confined-growth route from thermally stable layered vanadium bronze, representing the first two-dimensional (2D) metallic mesocrystal in inorganic compounds. Benefiting from their single-crystalline-like long-range electronic connectivity, VN MCNSs deliver an electrical conductivity of 1.44×10^5 S/m at room temperature, among the highest values observed for 2D nanosheets. Coupled with their unique pseudocapacitance, VN MCNS-based flexible supercapacitors afford a superior volumetric capacitance of 1,937 mF/cm3. Nitride MCNSs should have wide applications in the energy storage and conversion fields because their intrinsic high conductivity is coupled with the reactivity of inorganic lattices.