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A facile and sustainable synthetic strategy based on the coordination of natural polyphenols with metal ions is developed for the textural engineering of mesocrystals and hierarchical carbon nanomaterials. The desired control of coordination between ellagic acid and zinc ions enables the macroscopic self-assembly behavior of crystalline nanoplatelets to be tailored into round and elongated "peanut"-like micron-sized mesostructured particles. Direct carbonization of these mesocrystals generates hierarchically porous carbon particles in good yields, possessing bimodal micro- and mesoporous architecture along with a well-preserved macroscopic structure. The pore system provides both small storage sites, demonstrated by high CO2 uptake, and transport channels also accessible by larger molecules. [ABSTRACT FROM AUTHOR]

The traditional NH 3 production method (Haber-Bosch process) is currently complemented by electrochemical synthesis at ambient conditions, but the rather low selectivity (as indicated by the Faradaic efficiency) for the electrochemical reduction of molecular N 2 into NH 3 impedes the progress. Here, we present a powerful method to significantly boost the Faradaic efficiency of Au electrocatalysts to 67.8% for the nitrogen reduction reaction (NRR) by increasing their electron density through the construction of inorganic donor-acceptor couples of Ni and Au nanoparticles. The unique role of the electron-rich Au centers in facilitating the fixation and activation of N 2 was also investigated via theoretical simulation methods and then confirmed by experimental results. The highly coupled Au and Ni nanoparticles supported on nitrogen-doped carbon are stable for reuse and long-term performance of the NRR, making the electrochemical process more sustainable for practical application.

Herein we report a general liquid-mediated pathway for the growth of continuous polymeric carbon nitride (C3N4) thin films. The deposition method consists of the use of supramolecular complexes that transform to the liquid state before direct thermal condensation into C3N4 solid films. The resulting films exhibit continuous porous C3N4 networks on various substrates. Moreover, the optical absorption can be easily tuned to cover the solar spectrum by the insertion of an additional molecule into the starting complex. The strength of the deposition method is demonstrated by the use of the C3N4 layer as the electron acceptor in a polymer solar cell that exhibits a remarkable open-circuit voltage exceeding 1 V. The easy, safe, and direct synthesis of carbon nitride in a continuous layered architecture on different functional substrates opens new possibilities for the fabrication of many energy-related devices.