Xueyu Nie,Dongyue Luo,Huifen Ma,Longyan Wang,Chao Yang,Xike Tian,Yulun Nie
Currently, planting selenium-rich crops using inorganic selenium such as selenate and selenite is used to address human selenium deficiency problems. In this paper, besides the above two traditional inorganic selenium speciation, we chose a new organic selenium speciation of potassium selenocyanoacetate to investigate the different effects of selenium speciation on selenium absorption, selenium transformation and cadmium antagonism via foliar application. Planting experiments showed that the selenium content of garlic bulbs treated with organic selenium was 1.8–3.9 times higher than that of inorganic selenium. Additionally, the absorption and transformation efficiency of organic selenium in garlic was also the highest, reaching over 95 %. Importantly, it was noteworthy that the cadmium content in bulbs treated with organic selenium was significantly lower than the Chinese food safety standard (0.2 mg/kg). Hence, this study provides an efficient organic selenium speciation which is beneficial to meet human selenium requirements and ensure safe utilization of cadmium-contaminated soils.
Mingrui Tang,Junsheng Yu,Hua Tang,Jiang Cheng,Lu Li
Silver antimony sulfide (AgSbS 2 ) is considered a promising photovoltaic absorber material because of its suitable bandgap, large absorption coefficient, and environmental friendliness. However, the photovoltaic performance of AgSbS 2 -based solar cells is far from expectation and the applications of AgSbS 2 are limited by the underdeveloped fabrication technology. Herein, an effective method is developed to improve the photovoltaic performance of devices by adding indium (In) into the Ag–Sb–S system followed by a selenization process. With the addition of In, the morphology uniformity and the crystallinity of the films are simultaneously improved due to the diminished defects such as pinholes and cracks, leading to a better heterojunction interface between Ag 1− x In 2 x Sb 1− x S y Se 2− y and CdS. The Hall effect measurements demonstrate that the carrier concentration of the films effectively increases to 8.16 × 10 14 cm −3 on adding In. The optical characterization suggests that In addition significantly enhances the optical absorption and broadens the absorption wavelength range. Furthermore, the conduction band offset between the absorber and the buffer layer is substantially reduced by adding In, which lessens the carrier recombination at the interface, increasing the carriers transport efficiency. The power conversion efficiency of the Ag 1− x In 2 x Sb 1− x S y Se 2− y device is largely improved from 0.74% (In/Sb = 0) to 1.98% (In/Sb = 0.47).
危险品化学品经营许可证（带存储）