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The bulk photovoltaic effect shift current (SC), a constant photocurrent generated by irradiating polar homogeneous non‐centrosymmetric materials has lately emerged as a possible option for next‐generation photovoltaic systems that may potentially overcome the Shockley–Queisser limits. The current work predicts gigantic and anisotropic SC with multiple peaks across a wide range of frequencies in pristine 2D monolayer α‐AsP and α‐NP based on first‐principle calculations. The dominant SC tensors components hosted by 2D monolayer α‐AsP and α‐NP are the in‐plane, and reaches peaks of −154 µАV−2, and 87 µАV−2, respectively, in the UV region. The SC magnitudes of the α‐AsP are not significantly affected by the spin‐orbital coupling, while in α‐NP, no such effect occurs. This study recommends new photovoltaic materials with strong SC peaks spread across the electromagnetic spectrum, largely within the UV region. [ABSTRACT FROM AUTHOR]

The performance of lithium–sulfur (Li–S) battery is strongly dependent on the sulfur electrodes materials. Due to the chemical interaction between electrodes and intermediates produced in charging and discharging process, the Janus‐polar two dimensional (2D) electrode materials can enhance the electrochemical performance of Li–S battery by overcoming shuttle effect and increasing diffusion rates. Here, it is explored the structural, electronic, and dynamic characteristics of Li ion, S8 cluster, and lithium polysulfides adsorbed over Janus Phosphorus Nitride monolayer with blue phosphorene phase (b‐PN) by using first‐principles calculations. The reported findings highlight potential of the b‐PN monolayer as a good host material, given that the large absorption energies of different clusters vary from −0.47 to −3.78 eV, which can suppress shuttle effect effectively. These strong adsorptions are origin from the chemical interaction between nitrogen atoms of the b‐PN and Li atoms in lithium polysulfides in present work. Particularly, it is predicted that b‐PN monolayer has extremely small diffusion barriers for Li ion and Li2S8 clusters of 0.10 and 0.03 eV, which leading to a higher battery charge and discharge rate than reported graphene and MoS2. It is hoped that this efficient strategy for promising host materials of sulfur‐electrode guides the development of next‐generation lithium–sulfur batteries. [ABSTRACT FROM AUTHOR]

Recent reports have shown that self-assembled monolayers (SAMs) can induce doping effects in graphene transistors. However, a lack of understanding persists surrounding the quantitative relationship between SAM molecular design and its effects on graphene. In order to facilitate the fabrication of next-generation graphene-based devices it is important to reliably and predictably control the properties of graphene without negatively impacting its intrinsic high performance. In this study, SAMs with varying dipole magnitudes/directions are utilized and these values are directly correlated to changes in performance seen in graphene transistors. It is found that, by knowing the z-component of the SAM dipole, one can reliably predict the shift in graphene charge neutrality point after taking into account the influence of the metal electrodes (which also play a role in doping graphene). This relationship is verified through density functional theory and comprehensive device studies utilizing atomic force microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, and electrical characterization of graphene transistors. It is shown that properties of graphene transistors can be predictably controlled with SAMs when considering the total doping environment. Additionally, it is found that methylthio-terminated SAMs strongly interact with graphene allowing for a cleaner graphene transfer and enhanced charge mobility. [ABSTRACT FROM AUTHOR]