Understanding the transformation of graphitic carbon nitride (g-C3N4) is essential to assess nanomaterial robustness and environmental risks. Using an integrated experimental and simulation approach, our work has demonstrated that the photoinduced hole (h+) on g-C3N4 nanosheets significantly enhances nanomaterial decomposition under •OH attack. Two g-C3N4 nanosheet samples D and M2 were synthesized, among which M2 had more pores, defects, and edges, and they were subjected to treatments with •OH alone and both •OH and h+. Both D and M2 were oxidized and released nitrate and soluble organic fragments, and M2 was more susceptible to oxidation. Particularly, h+ increased the nitrate release rate by 3.37–6.33 times even though the steady-state concentration of •OH was similar. Molecular simulations highlighted that •OH only attacked a limited number of edge-site heptazines on g-C3N4 nanosheets and resulted in peripheral etching and slow degradation, whereas h+ decreased the activation energy barrier of C–N bond breaking between heptazines, shifted the degradation pathway to bulk fragmentation, and thus led to much faster degradation. This discovery not only sheds light on the unique environmental transformation of emerging photoreactive nanomaterials but also provides guidelines for designing robust nanomaterials for engineering applications.

A general solution-phase synthetic strategy is developed to construct both porous organic cages (POCs) and covalent organic frameworks (COFs) by simply stirring and heating organic solvent/water solutions of aldehydes and amines in the presence of MOH (M = Na, K, and Cs).

The structures of Pd islands at three different Pd coverages (0.028, 0.064, and 0.150 monolayer (ML)) on Ag(111) were studied at room temperature with scanning tunneling microscopy (STM). While previous studies have shown that the structure and composition of Pd islands on Ag(111) change at elevated temperatures, we found that Ag atoms migrate to cover the Pd islands even at room temperature. These Ag atoms occupy sites in the middle of the islands, and second layer growth begins at these sites. The migration of Ag atoms leads to the formation of vacancy islands in the Ag(111) terraces. Upon annealing to 340 K, the majority of the Pd islands are encapsulated by Ag atoms to form an Ag/Pd/Ag(111) structure. However, upon further annealing the composition of some islands at a Pd coverage of 0.150 ML changed to Ag/Ag/Pd/Ag(111).

On-surface synthesis via covalent coupling of adsorbed precursor molecules on metal surfaces has emerged as a promising strategy for the design and fabrication of novel organic nanoarchitectures with unique properties and potential applications in nanoelectronics, optoelectronics, spintronics, catalysis, etc. Surface-chemistry-driven molecular engineering (i.e., bond cleavage, linkage, and rearrangement) by means of thermal activation, light irradiation, and tip manipulation plays critical roles in various on-surface synthetic processes, as exemplified by the work from the Ernst group in a prior issue of ACS Nano. In this Perspective, we highlight recent advances in and discuss the outlook for on-surface syntheses and molecular engineering of carbon-based nanoarchitectures.

With the rapid development of the Internet of things (IoT) technology, the application of IoT has been expanded greatly, and the disadvantages of the traditional battery power supply have become increasingly prominent. The power supply mode limits the development of the concrete structural health monitoring network. And the application of magnetic resonance coupled wireless power transfer technology can solve the problem of power supply to sensors embedded in concrete. The corrected transmission efficiency considering the concrete conductivity is proposed which establishes the relationship between the electromagnetic field and the circuit model. And the field-circuit coupled model of asymmetric wireless power transfer system in concrete is developed. The effects of radial offset and axial dislocation on the transmission efficiency at different concrete conductivity are further analyzed. The relationship between the resonant frequency and the transmission efficiency in different concrete conductivity is analyzed, and an optimization scheme is proposed to improve the transmission efficiency. Finally, the experimental setups are established, and the theoretical analysis is verified. The conclusions cannot only break through the bottleneck of the scale of the concrete structural health monitoring network but also further releases the application potential of IoT.