Establishing highly effective charge transfer channels in carbon nitride (C3N4) for enhancing its photocatalytic activity is still a challenging issue. Herein, for the first time, the engineering of C3N4 layers with single‐atom Cu bonded with compositional N (CuNx) is demonstrated to address this challenge. The CuNx is formed by intercalation of chlorophyll sodium copper salt into a melamine‐based supramolecular precursor followed by controlled pyrolysis. Two groups of CuNx are identified: in one group each of Cu atoms is bonded with three in‐plane N atoms, while in the other group each of Cu atoms is bonded with four N atoms of two neighboring C3N4 layers, thus forming both in‐plane and interlayer charge transfer channels. Importantly, ultrafast spectroscopy has further proved that CuNx can greatly improve in‐plane and interlayer separation/transfer of charge carriers and in turn boost the photocatalytic efficiency. Consequently, the catalyst exhibits a superior visible‐light photocatalytic hydrogen production rate (≈212 µmol h−1/0.02 g catalyst), 30 times higher than that of bulk C3N4. Moreover, it leads to an outstanding conversion rate (92.3%) and selectivity (99.9%) for the oxidation of benzene under visible light.

Graphene quantum dots were modified on hexagonal tubular carbon nitride to form a composite photocatalyst by freeze‐drying technology. With an optimum loading amount of 0.15 wt % GQDs, the composite photocatalyst exhibits an improved visible‐light photocatalytic performance for hydrogen evolution (112.1 μmol h−1) that is about 9 times higher than that of bulk carbon nitride. During the photocatalytic reaction, graphene quantum dots play a photosensitizer role and an electron reservoir, which can extend the visible‐light response of the photocatalyst, decrease its band gap, and improve the separation efficiency of photoinduced electron–hole pairs. The graphene quantum dots can also absorb the long‐wavelength light and then emit the shorter wavelength light based on its upper transfer luminescence properties, which also contribute to the utilization of visible light. This finding demonstrates that the graphene quantum‐dot modification is a promising method to improve visible‐light photocatalytic activities for traditional photocatalysts.

The electrocatalytic activity of carbon-based non-precious metal composites towards oxygen reduction reaction (ORR) is far from that of the recognized Pt/C catalyst. Thus, it is necessary to exploit novel catalysts based on multicomponent carbon-based composites with both high activity and high stability. Herein, a bottom-up strategy was used for constructing bamboo-like N-doped graphitic CNTs with a few encapsulated Co and VN nanoparticles (namely, NGT-CoV) by adopting melamine as both a nitrogen source and a carbon source. During the synthesis, melamine initially coordinated with cobalt and vanadium ions and then decomposed into carbon nitride nanosheet structures. Simultaneously, cobalt ions/clusters were converted into metal nanocatalysts by the reduced gases that were generated, which further rearranged the carbon nitride nanostructures to form N-doped CNTs. The presence of vanadium species strengthened the electronic structure and increased the contents of Co and N species by enhancing the interactions among Co and N species. The optimized NGT-CoV-45-900 exhibited an E of 0.92 V (vs. RHE), an E of 0.81 V (vs. RHE), and a Tafel slope of 66.1 mV dec in the ORR. It also displayed much higher durability (a negative shift in E of only 11 mV after 10 000 cycles) and methanol tolerance than a commercial Pt/C catalyst. The excellent performance should be attributed to the high exposure level of active sites that originated from Co-N, VN and N-doped bamboo-like graphitic CNTs. Moreover, the skeleton composed of hollow graphitic ultra-long CNTs could not only provide smooth mass transport pathways but also facilitate fast electron transfer.

Polyoxometalates (POMs) are anionic molecular metal oxides with expansive diversity in terms of their composition, structure, nuclearity and charge. Within this vast collection of compounds are dominant structural motifs (POM...

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A kind of green SiC fine powder was characterized by XRD and UV-Vis diffuse reflectance, and studied in the photocatalytic splitting of water. The results showed that the green SiC fine powder can absorb visible light and split water with the formation of hydrogen under visible light irradiation. The activity is affected significantly by the initial pH of solutions and the types of cheap reagents, where the addition of OH -or S 2-leads to a remarkable increase in the activity.

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Conjugated coordination polymers (CPs) with designable and predictable structures have drawn tremendous attention in recent years. However, the poor electrical conductivity and low structural stability seriously restrict their practical applications in electronic devices. Herein, the rational design and synthesis of a hierarchically structured 2D bimetallic CoNi‐hexaaminobenzene CPs derived from Co(OH)2 are reported as an efficient oxygen evolution reaction (OER) self‐supported electrode. The as‐obtained electrode possesses high electrochemical surface area and intrinsic activity, exhibiting high electrochemical catalytic activity, favorable reaction kinetics performance, and strong durability compared with those of the powder catalysts. As a result, the electrode delivers low overpotential of 219 mV @ 10 mA cm−2 and Tafel slope of 42 mV dec−1 as well as 91.3% retention of current density after 24 h of reaction time. The results of density functional theory computations reveal that the synergistic effect of Co and Ni plays an important role in OER. This work not only presents a strategy to fabricate advanced self‐supported electrodes with abundant and dense active sites, but also promotes the development of conjugated CPs for electrocatalysis.