The Mn doping effects on the gate-tunable transport properties of topological Dirac semimetal Cd3As2 films have been investigated.Mn-doped Cd3As2 films are directly grown on GaAs(111)B substrates by molecular-beam epi...The Mn doping effects on the gate-tunable transport properties of topological Dirac semimetal Cd3As2 films have been investigated.Mn-doped Cd3As2 films are directly grown on GaAs(111)B substrates by molecular-beam epitaxy,during which the single crystal phase can be obtained with Mn concentration less than 2%.Shubnikov-de Haas oscillation and quantum Hall effect are observed at low temperatures,and electrons are found to be the dominant carrier in the whole temperature range.Higher Mn content results in smaller lattice constant,lower electron mobility and larger effective band gap,while the carrier density seems to be unaffected by Mn-doping.Gating experiments show that Shubnikov-de Haas oscillation and quantum Hall effect are slightly modulated by electric field,which can be explained by the variation of electron density.Our results provide useful information for understanding the magnetic element doping effects on the transport properties of Cd3As2 films.展开更多
In recent years, some important research indicated that the visible-light activity of photocatalysts could be enhanced via incorporating p-block non-metal elements into the lattice. In this paper, we investigated the ...In recent years, some important research indicated that the visible-light activity of photocatalysts could be enhanced via incorporating p-block non-metal elements into the lattice. In this paper, we investigated the electronic structures of pure and different non-metal （C, N, S, F, Cl, and Br） doped α-Bi2O3 using first-principles calculations based on the density functional theory. The band structures, the electronic densities of states, and the effective masses of electrons and holes for doped α-Bi2O3 were obtained and analyzed. The N and S dopings narrowed the band gap and reduced the effective mass of the carriers, which are beneficial for the photocatalytic performance. The theoretical predication was further confirmed by the experimental results.展开更多
A new inorganic-organic hybrid framework microporous material Cd 3(BDC) 0.5(BTC) 2·(DMF)(H 2O)·3DMF·H 3O·H 2O, in which two kinds of carboxylate ligands coordinate with cadmium ions synchronously, ...A new inorganic-organic hybrid framework microporous material Cd 3(BDC) 0.5(BTC) 2·(DMF)(H 2O)·3DMF·H 3O·H 2O, in which two kinds of carboxylate ligands coordinate with cadmium ions synchronously, was obtained under a mild synthesis condition. The titled compound is crystallized in a monoclinic system, space group P2(1)/c with a=1.584 7(7) nm, b=1.426 7(6) nm, c=1.936 3(6) nm, β=113.186(7)°, V=4.024 6(3) nm 3, Z=4, D X=1.947 mg/m 3, M r=1 179.92, μ=1.662 mm -1, F(000)=2 344, R=0.074 8, wR=0.215 1. Three cadmium centers link with each other through BDC or BTC ligand to form a 3-D open framework.展开更多
In this paper, the electrochemical synthesis method was used to prepare γ-Bi2O3. Ultrafine Bi metal powder was first synthesized by electrochemical method at room temperature in a single cell .The anode comprised the...In this paper, the electrochemical synthesis method was used to prepare γ-Bi2O3. Ultrafine Bi metal powder was first synthesized by electrochemical method at room temperature in a single cell .The anode comprised the sacrificial metal Bi; the cathode was Pt; the NaOH solution was used as the electrolyte. The ultrafine Bi metal powder had a special chemical reactivity. Then γ-Bi2O3 was prepared by the reaction of ultrafine Bi and NaOH solution. The effect of the concentration of NaOH solution, reaction temperature and additive were studied. The principle of the reaction was discussed. The component of the product was determined by atomic emission spectrometry and EDTA titration analysis. XRD, SEM ,TEM and DTA were employed for the characterization of the obtained products.展开更多
基金supported by NSFC(Grants Nos.U1632264 and 11704374)the the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant Nos.XDB44000000 and QYZDY-SSW-JSC015)。
文摘The Mn doping effects on the gate-tunable transport properties of topological Dirac semimetal Cd3As2 films have been investigated.Mn-doped Cd3As2 films are directly grown on GaAs(111)B substrates by molecular-beam epitaxy,during which the single crystal phase can be obtained with Mn concentration less than 2%.Shubnikov-de Haas oscillation and quantum Hall effect are observed at low temperatures,and electrons are found to be the dominant carrier in the whole temperature range.Higher Mn content results in smaller lattice constant,lower electron mobility and larger effective band gap,while the carrier density seems to be unaffected by Mn-doping.Gating experiments show that Shubnikov-de Haas oscillation and quantum Hall effect are slightly modulated by electric field,which can be explained by the variation of electron density.Our results provide useful information for understanding the magnetic element doping effects on the transport properties of Cd3As2 films.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.51072012 and 51272015)
文摘In recent years, some important research indicated that the visible-light activity of photocatalysts could be enhanced via incorporating p-block non-metal elements into the lattice. In this paper, we investigated the electronic structures of pure and different non-metal （C, N, S, F, Cl, and Br） doped α-Bi2O3 using first-principles calculations based on the density functional theory. The band structures, the electronic densities of states, and the effective masses of electrons and holes for doped α-Bi2O3 were obtained and analyzed. The N and S dopings narrowed the band gap and reduced the effective mass of the carriers, which are beneficial for the photocatalytic performance. The theoretical predication was further confirmed by the experimental results.
文摘A new inorganic-organic hybrid framework microporous material Cd 3(BDC) 0.5(BTC) 2·(DMF)(H 2O)·3DMF·H 3O·H 2O, in which two kinds of carboxylate ligands coordinate with cadmium ions synchronously, was obtained under a mild synthesis condition. The titled compound is crystallized in a monoclinic system, space group P2(1)/c with a=1.584 7(7) nm, b=1.426 7(6) nm, c=1.936 3(6) nm, β=113.186(7)°, V=4.024 6(3) nm 3, Z=4, D X=1.947 mg/m 3, M r=1 179.92, μ=1.662 mm -1, F(000)=2 344, R=0.074 8, wR=0.215 1. Three cadmium centers link with each other through BDC or BTC ligand to form a 3-D open framework.
文摘In this paper, the electrochemical synthesis method was used to prepare γ-Bi2O3. Ultrafine Bi metal powder was first synthesized by electrochemical method at room temperature in a single cell .The anode comprised the sacrificial metal Bi; the cathode was Pt; the NaOH solution was used as the electrolyte. The ultrafine Bi metal powder had a special chemical reactivity. Then γ-Bi2O3 was prepared by the reaction of ultrafine Bi and NaOH solution. The effect of the concentration of NaOH solution, reaction temperature and additive were studied. The principle of the reaction was discussed. The component of the product was determined by atomic emission spectrometry and EDTA titration analysis. XRD, SEM ,TEM and DTA were employed for the characterization of the obtained products.
