Charge Carrier Mediation and Ferromagnetism induced in MnBi6Te10 Magnetic Topological Insulators by antimony doping

A new kind of intrinsic magnetic topological insulators (MTI) MnBi2Te4 family have shed light on the observation of novel topological quantum effect such as quantum anomalous Hall effect (QAHE). However, the strong anti-ferromagnetic (AFM) coupling and high carrier concentration in the bulk hinder the practical applications. In closely related materials MnBi4Te7 and MnBi6Te10, the interlayer magnetic coupling is greatly suppressed by Bi2Te3 layer intercalation. However, AFM is still the ground state in these compounds. Here by magnetic and transport measurements, we demonstrate that Sb substitutional dopant plays a dual role in MnBi6Te10, which can not only adjust the charge carrier type and the concentration, but also induce the solid into a ferromagnetic (FM) ground state. AFM ground state region which is also close to the charge neutral point can be found in the phase diagram of Mn(SbxBi1-x)6Te10 when x ~ 0.25. An intrinsic FM-MTI candidate is thus demonstrated, and it may take a step further for the realization of high-quality and high-temperature QAHE and the related topological quantum effects in the future.

Pure and Sb-doped ZrO2 for removal of IO3− from radioactive waste solutions

Radioactive 129I with a long half-life (1.57 × 107 y) and high mobility is a serious radiohazard and one of the top risk radionuclides associated with its accidental and planned releases to nature. The complex speciation chemistry of iodine makes its removal a complicated task, and usually a single method is not able to remove all iodine species. Especially its oxidized form iodate (IO3−) lacks a selective and effective removal method. Here, the granular aggregates of hydrous zirconium oxides with and without antimony doping were tested for IO3− removal and the effects of contact time, competing anions in different concentrations and pH were examined. The materials showed high selectivity for IO3− (Kd over up to 50,000 ml/g) in the presence of competing ions and relatively fast uptake kinetics (eq. < 1 h). However, B(OH)4− and SO42−, as competing ions, lowered the iodate uptake significantly in basic and acidic solution, respectively. The suitability of the materials for practical applications was tested in a series of column experiments where the materials showed remarkably high apparent capacity for the IO3− uptake (3.2–3.5 mmol/g). Graphic abstract

Dopant-induced cationic bivalency in hierarchical antimony-doped tin oxide nano-particles for room-temperature SO2 sensing

Antimony doping in tin oxide triggered generation of tin bivalency and it is the variation in ratio of 2+ and 4+ states of tin that determines the efficiency of room temperature SO2 sensing.

Antimony doping to greatly enhance the electrocatalytic performance of Sr2Fe1.5Mo0.5O6-δ perovskite as ceramic anode for solid oxide fuel cell

Perovskite oxide Sr2Fe1.5Mo0.5O6-δ (SFM) has caused much attention as a potential ceramic anode material for solid oxide fuel cell. In this work, antimony is primarily proposed to partially replace the...