Sorption properties of U(VI) and Th(IV) on two-dimensional Molybdenum Disulfide (MoS2) nanosheets: Effects of pH, ionic strength, contact time, humic acids and temperature

2018 ◽  
Vol 11 ◽  
pp. 328-338 ◽  
Author(s):  
Xue Li ◽  
Qian Li ◽  
Wensheng Linghu ◽  
Runpu Shen ◽  
Baoshan Zhao ◽  
...  
2019 ◽  
Vol 75 ◽  
pp. 115-123 ◽  
Author(s):  
Jingjing Wang ◽  
Bihong He ◽  
Xiaoyan Wei ◽  
Ping Li ◽  
Jianjun Liang ◽  
...  

Author(s):  
Mengxia Wang ◽  
Qi Han ◽  
Yufei Shu ◽  
Kunkun Wang ◽  
Li Wang ◽  
...  

Mercury (Hg) contamination in groundwater has been recognized as a serious threat to human health and ecological system all over the world. This study demonstrated two-dimensional (2D) molybdenum disulfide (MoS2)...


Nanophotonics ◽  
2020 ◽  
Vol 9 (16) ◽  
pp. 4719-4728
Author(s):  
Tao Deng ◽  
Shasha Li ◽  
Yuning Li ◽  
Yang Zhang ◽  
Jingye Sun ◽  
...  

AbstractThe molybdenum disulfide (MoS2)-based photodetectors are facing two challenges: the insensitivity to polarized light and the low photoresponsivity. Herein, three-dimensional (3D) field-effect transistors (FETs) based on monolayer MoS2 were fabricated by applying a self–rolled-up technique. The unique microtubular structure makes 3D MoS2 FETs become polarization sensitive. Moreover, the microtubular structure not only offers a natural resonant microcavity to enhance the optical field inside but also increases the light-MoS2 interaction area, resulting in a higher photoresponsivity. Photoresponsivities as high as 23.8 and 2.9 A/W at 395 and 660 nm, respectively, and a comparable polarization ratio of 1.64 were obtained. The fabrication technique of the 3D MoS2 FET could be transferred to other two-dimensional materials, which is very promising for high-performance polarization-sensitive optical and optoelectronic applications.


Agronomy ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1067
Author(s):  
Aleksandra Ukalska-Jaruga ◽  
Romualda Bejger ◽  
Guillaume Debaene ◽  
Bożena Smreczak

The objective of this paper was to investigate the molecular characterization of soil organic matter fractions (humic substances (HS): fulvic acids-FAs, humic acids-HAs, and humins-HNs), which are the most reactive soil components. A wide spectrum of spectroscopic (UV–VIS and VIS–nearIR), as well as electrochemical (zeta potential, particle size diameter, and polydispersity index), methods were applied to find the relevant differences in the behavior, formation, composition, and sorption properties of HS fractions derived from various soils. Soil material (n = 30) used for the study were sampled from the surface layer (0–30 cm) of agricultural soils. FAs and HAs were isolated by sequential extraction in alkaline and acidic solutions, according to the International Humic Substances Society method, while HNs was determined in the soil residue (after FAs and HAs extraction) by mineral fraction digestion using a 0.1M HCL/0.3M HF mixture and DMSO. Our study showed that significant differences in the molecular structures of FAs, Has, and HNs occurred. Optical analysis confirmed the lower molecular weight of FAs with high amount of lignin-like compounds and the higher weighted aliphatic–aromatic structure of HAs. The HNs were characterized by a very pronounced and strong condensed structure associated with the highest molecular weight. HAs and HNs molecules exhibited an abundance of acidic, phenolic, and amine functional groups at the aromatic ring and aliphatic chains, while FAs mainly showed the presence of methyl, methylene, ethenyl, and carboxyl reactive groups. HS was characterized by high polydispersity related with their structure. FAs were characterized by ellipsoidal shape as being associated to the long aliphatic chains, while HAs and HNs revealed a smaller particle diameter and a more spherical shape caused by the higher intermolecular forcing between the particles. The observed trends directly indicate that individual HS fractions differ in behavior, formation, composition, and sorption properties, which reflects their binding potential to other molecules depending on soil properties resulting from their type. The determined properties of individual HS fractions are presented as averaged characteristics over the examined soils with different physico-chemical properties.


Nanoscale ◽  
2021 ◽  
Author(s):  
Ziqi Yang ◽  
Huiqiao Guo ◽  
Wenbin You ◽  
Zhengchen Wu ◽  
Liting Yang ◽  
...  

Structural engineering represents a major trend in two-dimensional (2D) material fields on microscopic interfacial electric/dielectric property and macroscopic device strategy. 2D Molybdenum disulfide (MoS2) with semiconductive feature and lamellar architecture...


Processes ◽  
2020 ◽  
Vol 8 (5) ◽  
pp. 504 ◽  
Author(s):  
Siyi Huang ◽  
Ziyun You ◽  
Yanting Jiang ◽  
Fuxiang Zhang ◽  
Kaiyang Liu ◽  
...  

Owing to their peculiar structural characteristics and potential applications in various fields, the ultrathin MoS2 nanosheets, a typical two-dimensional material, have attracted numerous attentions. In this paper, a hybrid strategy with combination of quenching process and liquid-based exfoliation was employed to fabricate the ultrathin MoS2 nanosheets (MoS2 NS). The obtained MoS2 NS still maintained hexagonal phase (2H-MoS2) and exhibited evident thin layer-structure (1–2 layers) with inconspicuous wrinkle. Besides, the MoS2 NS dispersion showed excellent stability (over 60 days) and high concentration (0.65 ± 0.04 mg mL−1). The MoS2 NS dispersion also displayed evident optical properties, with two characteristic peaks at 615 and 670 nm, and could be quantitatively analyzed with the absorbance at 615 nm in the range of 0.01–0.5 mg mL−1. The adsorption experiments showed that the as-prepared MoS2 NS also exhibited remarkable adsorption performance on the dyes (344.8 and 123.5 mg g−1 of qm for methylene blue and methyl orange, respectively) and heavy metals (185.2, 169.5, and 70.4 mg g−1 of qm for Cd2+, Cu2+, and Ag+). During the adsorption, the main adsorption mechanisms involved the synergism of physical hole-filling effects and electrostatic interactions. This work provided an effective way for the large-scale fabrication of the two-dimensional nanosheets of transition metal dichalcogenides (TMDs) by liquid exfoliation.


Soil Research ◽  
1981 ◽  
Vol 19 (1) ◽  
pp. 93 ◽  
Author(s):  
GP Gillman

The cation exchange capacity of six surface soils from north Queensland and Hawaii has been measured over a range of pH values (4-6) and ionic strength values (0.003-0.05). The results show that for variable charge soils, modest changes in electrolyte ionic strength are as important in their effect on caton exchange capacity as are changes in pH values.


Sign in / Sign up

Export Citation Format

Share Document