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Functional platinum-based carbonous nanostructures play important roles in exploring new electrode materials by constructing sensitive and selective platform in the electrochemical detection. In recent years, intense research efforts have focused on boosting the performance of platinum with desirable activity and stability. This work reports a facile strategy for the synthesis of platinum-based nitrogen-doped porous C x N 1-x compounds (Pt-pC x N 1-x ) with excellent enzyme-like activity. In the strategy, Pt-pC x N 1-x was simply prepared by in situ synthesis through a one-step microwave-assisted heating procedure, resulting with subnanometer-size (∼2.5 nm) platinum-based nanoparticles (Pt-BNPs) loaded on the multi-dimensional C x N 1-x structure. Due to the enriched edge and corner atoms, Pt-pC x N 1-x showed excellent intrinsic peroxidase-like activity. Meanwhile, it was demonstrated that Pt-pC x N 1-x possessed a lower Michaelis Constant ( K m = 0.104) compared with horseradish peroxidase (HRP) ( K m = 0.416) in the presence of 3,3,5,5-tetramethylbenzidine (TMB) and hydrogen peroxide (H 2 O 2 ). Moreover, the Pt-pC x N 1-x behaved better property and lower cost in H 2 O 2 electrochemical detection compared with the pC x N 1-x and Pt-BNPs. The detection results exhibited a low detection limit (2.29 μM) and a wide linear range (0.025 to 5.725 mM), which revealed its superior potential in H 2 O 2 electrochemical detection. Therefore, the Pt-pC x N 1-x may find a potential application in constructing electrochemical biosensors.

Control of structure-enriched abundant unsaturated or dangling bonds can precisely and effectively tune the activity and durability of materials. In this study, a new strategy to obtain fusiform nanoarchitectures (FNAs) has been found for the first time using Te nanostructures as the model materials. TeFNA could be transformed from Te nanorods (NRs) with different diameter (50, 25 nm), even the ultrathin nanowires (NWs) (10 nm). Besides, a novel perspective into the preliminary mechanism combining collision theory with density functional theory simulations was proposed to explain the transformation progress. In the mixing system of hexadecyl trimethylammonium bromide (CTAB) solution, the Te NR/NWs keep the translational motion together with the centroid rotation. The velocity of the two ends of TeNR/NWs is higher than that in the center under the reaction condition based on collision theory; meanwhile, the summation energy of both O2 and CTAB put on Te (0001) surface is −606.992 eV, which means that the T...

A novel and green multifunctional nanoplatform as a nanocarrier for drug delivery, cell imaging, and phototherapy has been engineered. The nanoplatform is composed of stabilized carbon spheres (CSs) as cores, a coated polydopamine (PDA) shell, targeted folic acid (FA), and the loaded anticancer drug indocyanine green (ICG), obtaining CSs@PDA-FA@ICG nanocomposites (NCs). The biocompatible PDA shell provided a high fluorescence quenching efficiency and a surface rich in functional groups for anchoring FA for targeting cancer cells. Aromatic ICG could be effectively loaded into the CSs@PDA-FA system via hydrophobic interactions and π-π stacking with a loading efficiency of 58.9%. Notably, the activated NIR fluorescence in an intracellular environment made CSs@PDA-FA@ICG a sensitive "OFF" to "ON" nanoprobe that can be used for NIR imaging. Moreover, compared to ICG alone, the CSs@PDA-FA@ICG NCs could induce efficient photoconversion for simultaneous synergetic photodynamic therapy (PDT) and photothermal therapy (PTT) under a single NIR laser irradiation. The results demonstrated that CSs@PDA-FA@ICG NCs as a targeted and activated nanoplatform provide new opportunities to facilitate the accurate diagnosis of cancer and enhanced treatment efficacy. This work stimulates more interest in the design of the facile surface functionalization strategy to construct other multifunctional nanocomposites, such as nanotubes and nanorods.

In this work, a high-capacity supercapacitor material based on functionalized three-dimensional (3D) porous graphene was fabricated by low temperature hydrothermal treatment of graphene oxide (GO) using both ionic liquid (IL) and SiO2 spheres as "spacers". In the synthesis, the introduction of dual "spacers" effectively enlarged the interspace between graphene sheets and suppressed their re-stacking. In addition, the IL also acted as a structure-directing agent playing a crucial role in inducing the formation of unique 3D architectures. Consequently, fast electron/ion transport channels were successfully constructed and numerous oxygen-containing groups on graphene sheets were effectively reserved, which had unique advantages in decreasing ion diffusion resistance and providing additional pseudocapacitance. As expected, the obtained material exhibited superior specific capacitance and rate capability compared to single "spacer" designed electrodes and simultaneously maintained excellent cycling stability. In particular, there was nearly no loss of its initial capacitance after 3000 cycles. In addition, we further assembled a symmetric two-electrode device using the material, which showed outstanding flexibility and low equivalent series resistance (ESR). More importantly, it was capable of yielding a maximum power density of about 13.3 kW kg(-1) with an energy density of about 7.0 W h kg(-1) at a voltage of 1.0 V in 1 M H2SO4 electrolyte. All these impressive results demonstrate that the material obtained by this approach is greatly promising for application in high-performance supercapacitors.