Publications by authors named "Ningning Xuan"

The research presented in this paper introduces a novel environmental energy-harvesting technology that harnesses electricity from the evaporation of water using porous structural materials. Specifically, a strategy employing paper-based hydroelectric generators (p-HEGs) is proposed to capture the energy produced during water evaporation and convert it into usable electricity. The p-HEGs offer several advantages, including simplicity in fabrication, low cost, and reusability.

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The booming frontier of electrochemistry is radically transforming the landscape of global chemical and energy industry. Most recent advancements in electrocatalysts have been built on trial and error, lacking model experiments to illuminate the fundamental factors hidden behind, such as phase, conductivity, and surface coordination environment. Here, we use phase-controllable, highly oriented two-dimensional MoTe as the model catalysts.

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Because of the strong quantum confinement effect, few-layer γ-InSe exhibits a layer-dependent band gap, spanning the visible and near infrared regions, and thus recently has been drawing tremendous attention. As a two-dimensional material, the mechanical flexibility provides an additional tuning knob for the electronic structures. Here, for the first time, we engineer the band structures of few-layer and bulk-like InSe by uniaxial tensile strain and observe a salient shift of photoluminescence peaks.

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Two-dimensional (2D) materials have attracted broad research interests across various nonlinear optical (NLO) studies, including nonlinear photoluminescence (NPL), second harmonic generation (SHG), transient absorption (TA), and so forth. These studies have unveiled important features and information of 2D materials, such as in grain boundaries, defects, and crystal orientations. However, as most research studies focused on the intrinsic NLO processes, little attention has been paid to the substrates underneath.

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Monolayer hexagonal boron nitride (h-BN) possesses a wide bandgap of ~6 eV. Trimming down the bandgap is technically attractive, yet poses remarkable challenges in chemistry. One strategy is to topological reform the h-BN's hexagonal structure, which involves defects or grain boundaries (GBs) engineering in the basal plane.

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Graphene, the sp carbonaceous two-dimensional (2D) material, is gaining more attention in recent electrochemical studies. However, this atomic thick electrode usually suffers with surface contamination and poor electrochemical endurance. To overcome the drawbacks, we developed a PMMA-assisted, flipped transfer method to fabricate the graphene electrode with pristine surface and prolonged lifetime in hydrogen evolution reaction (HER).

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