LAUSR

Graphitic carbon nitrides (g-CNxHys) have emerged as promising candidates for driving photocatalytic H2 evolution under visible light, CO2 reduction, and other renewable energy applications owing to their native high surface area, bandgap in the visible regime, and inexpensive synthesis routes [1]. Calcination of various N-rich precursors yields layered compounds with interplanar spacings of ~3.2 Å. Although commonly referred to as “g-C3N4”, the average structure of g-CNxHys are consistent with polymeric melon (C2N3H) whose in-plane structure is composed of amine (N-Hx) bridged heptazine (C6N7) building blocks (Figure 1a) [2]. However, structural differences between different g-CNxHys are not well understood as X-ray diffraction (XRD) and related measurements are limited to the bulk. High spatial resolution techniques, such as transmission electron microscopy (TEM), may be leveraged to probe the in-plane structure/disorder in these materials.