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Constructing high‐performance‐2D heterostructures and deciphering the underlying microscopic mechanism of carrier dynamics are crucial in optoelectronic and photovoltaic applications. Here, taking black phosphorus (BP)/MoS2 heterostructure with type‐II band alignment as a prototypical example, the ab initio nonadiabatic molecular dynamics simulations demonstrate that the interlayer carrier dynamics are thickness dependent. Specifically, the electron transfer from a monolayer (1L)‐BP to MoS2 occurs quickly within 54 fs. In contrast, hole transfer can only be observed within 1 ps with BP's layer number N ≥ 2, triggered by the excitation of low‐frequency acoustic phonon and interlayer shear and breathing phonon modes within 100 cm–1 that enhances the interlayer coupling. Particularly, the electron and hole transfer time exhibits respectively linear and exponential dependence on the layer number N of BP component. The present findings shed new light on improving the process of ultrafast carrier dynamics of 2D heterostructures for photoconversion. [ABSTRACT FROM AUTHOR]

As release formulations, superabsorbent polymers have attracted considerable attentions to reduce herbicide leaching and mitigate contamination. For this purpose, this study dealt with preparation, characterization, and performance test of a novel amphoteric superabsorbent polymer in adsorption and release of 2, 4‐Dichlorophenoxyacetic acid (2, 4‐D) herbicide. LW‐g‐p(AA‐co‐DMDAAC) was successfully synthesized by using leather waste (LW) as raw material and acrylic acid (AA), and dimethyldiallylammonium chloride (DMDAAC) as monomers. Then, the resulting LW‐g‐p(AA‐co‐DMDAAC) was characterized before and after 2, 4‐D sorption by scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). In addition, LW‐g‐p(AA‐co‐DMDAAC) with great equilibrium swelling capacity of 3203 g/g in distilled water, 181 g/g in 0.9 wt % NaCl exhibited excellent performance of swelling. Two absorption peaks appeared at pH = 4 and 7 solely when swelling occurred, and the swelling behavior in pH = 7 satisfied the pseudo first‐order kinetic equation. Moreover, the sorbed 2, 4‐D reached at 68 mg/g and showed sustained release cycle of 45 days under acidic or alkaline conditions. Therefore, the sustained release pattern of 2, 4‐D as well as water absorbency made LW‐g‐p(AA‐co‐DMDAAC) suitable and potential candidate for controlling the release of herbicides to improve utilization and reduce environmental pollution. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48480. [ABSTRACT FROM AUTHOR]