Jingru Zhuang

Photocharging in carbon nitride materials is emerging as a promising route for light‐driven energy storage, yet the nature of the storage sites and their mechanisms remain elusive. Here, we investigate photocharging in poly(heptazine imide) (PHI), focusing on its protonated (H‐PHI) and sodium (Na‐PHI) forms. Using the photochemical dealkylation of triethylamine, we quantify the density of electron–proton (e ⁻ /H ⁺ ) pairs stored in these materials and define a descriptor, N _e : N _hept , to track photocharging at the molecular level. H‐PHI demonstrates superior electron storage and reactivity, attributed to its microporous 2D structure and favorable energetics. Theoretical modeling, combined with spectroscopic analysis, reveals the nature of the active heptazine sites and their transformation during charging. The material retains its structural and functional integrity across multiple cycles, underscoring its stability and recyclability. These insights open new avenues for the rational design of carbon nitride‐based semiconductors for light‐induced redox applications.

Photocharging in carbon nitride materials is emerging as a promising route for light‐driven energy storage, yet the nature of the storage sites and their mechanisms remain elusive. Here, we investigate photocharging in poly(heptazine imide) (PHI), focusing on its protonated (H‐PHI) and sodium (Na‐PHI) forms. Using the photochemical dealkylation of triethylamine, we quantify the density of electron–proton (e ⁻ /H ⁺ ) pairs stored in these materials and define a descriptor, N _e : N _hept , to track photocharging at the molecular level. H‐PHI demonstrates superior electron storage and reactivity, attributed to its microporous 2D structure and favorable energetics. Theoretical modeling, combined with spectroscopic analysis, reveals the nature of the active heptazine sites and their transformation during charging. The material retains its structural and functional integrity across multiple cycles, underscoring its stability and recyclability. These insights open new avenues for the rational design of carbon nitride‐based semiconductors for light‐induced redox applications.

A Pd nanocube-modified PHI composite was successfully fabricated via electrostatic self-assembly and effectively promoted the visible-light-driven hydrogenation of nitriles to primary amines.

ConspectusOrganic synthesis mediated by graphitic carbon nitrides (g-CNs) became a research hotspot primarily due to a combination of the following aspects: (1) the simple and convenient preparation of the material on a gram scale from inexpensive precursors, (2) the heterogeneous nature of the material, which allows for its easy recovery from the reaction mixture, chemical and thermal stability, and possibility to create nanostructures, such as membranes and thin films, and (3) the effective utilization of sustainable energy─photons in the UVA-vis range, which may be used to drive chemical reactions that are endergonic in the dark. By combining various spectroscopic techniques and the results of theoretical modeling, our group identified three modes of substrate activation by g-CN via (1) photoinduced electron transfer, (2) energy transfer, and (3) proton-coupled electron transfer/hydrogen atom transfer. In this Account, we discuss the chemical structure of the electronically excited state of g-CN. This information may be used to design rational pathways for substrate activation via the above-mentioned mechanisms. Using elemental sulfur (S₈) as a nearly 100% atom-efficient sulfurating agent, we developed a set of methods to incorporate sulfur atom(s) into the organic scaffold by means of g-CN photocatalysis. On the other hand, we identified S₈ as a more selective, compared to O₂, sacrificial oxidant to mediate a few net-oxidative photocatalytic transformations. Among the products of the developed synthetic methods are highly fluorescent heterocycles, artificial flavoring agents, and precursors for organic synthesis. While g-CNs are typically used by the community as photocatalysts under continuous light illumination (the sensitizer is regenerated many times in the catalytic cycle), our group contributed to understanding the ability of this class of materials to undergo photocharging, i.e., to store charges by forming long-lived radical species. We applied photocharged carbon nitrides as donors of electrons and protons in the dark in a series of organic transformations. We outline the current challenges and future development prospects of carbon nitride-mediated organic synthesis. At the same time, we provide guidance on the development of organic catalytic systems and material design at the molecular level.

Digital learning and gamification make studying chemistry more exciting and engaging. Interactive digital tools allow students to understand fundamental concepts of chemistry more easily. However, application of this knowledge is hampered by the lack of user-friendly chemistry simulators, in which students could apply their knowledge in a creative way. This paper describes the development of the application software – ChemChellenge. This software is intended for use primarily by undergraduate students studying chemistry and chemical engineers. The goal of the game is to design reaction equations that describe spontaneous chemical reactions. The application software has many features of video games, such as a developed reward system, that is based on principles of thermodynamics, customization of player’s chemistry laboratory and in-game currency. These features make gameplay less linear. As such, multiple solutions to the same task are possible. A case study of using ChemChallenge to teach thermodynamics at undergraduate level is described.