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Low‐dimensional materials and heterostructure photocatalysts are distinct research topics in artificial photocatalysis. The rational design of photocatalysts considering both aspects has established significant importance due to the fascinating advantages of superior charge carrier transport/transfer and photocatalytic performances. Graphitic carbon nitride (g‐C3N4), a captivating metal‐free and visible light‐active photocatalyst, has drawn interdisciplinary attention in the field of solar energy conversion and pollutant degradation because of its appropriate electronic band structure, excellent physicochemical stability, facile synthesis, and unique layered structure. The g‐C3N4‐based low‐dimensional heterostructures demonstrate various mechanisms for photogenerated charge carrier transfer including type I heterojunction, type II heterojunction, p–n heterojunction, Z‐scheme heterojunction, Schottky junction, and surface plasmon resonance (SPR) effect. Herein, the state‐of‐the‐art g‐C3N4‐based low‐dimensional heterostructure photocatalysts are analyzed to provide an insightful outlook with respect to doping and defect engineering, band structures tuning, and charged carrier dynamics to realize enhanced visible light absorption, improved photoinduced charge carrier transport/transfer, and spatially separated electron–hole pairs for improved photocatalytic performances. Furthermore, the potential application of g‐C3N4‐based low‐dimensional heterostructures for water splitting, CO2 reduction, and pollutant degradation is also presented. Finally, conclusion and invigorating perspective about challenges and opportunities for advanced design of g‐C3N4‐based low‐dimensional heterostructures are briefed.

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The synergy between nitrogen (N) and sulfur (S) in quaternary heteroatom-doped carbons is rarely probed, although these elements can significantly alter the performance of the oxygen evolution reaction (OER). Herein, quaternary heteroatom (N, S, P, O)-doped multishelled carbon (NSPO-C) nanospheres are synthesized from heteroatom-containing poly­(cyclotriphosphazene-codioxo-thiane) (PCD) polymer nanospheres. The contents of these quaternary heteroatoms were controlled via a facile carbonization process. The OER performance was tested, which was found to be related to the N and S contents, and the as-prepared NSPO-C-8 nanosphere anode with optimized contents of N (2.76 wt %) and S (1.52 wt %) showed a maximum OER activity, that is, it required a very low overpotential of 339 mV to obtain a current density of 10 mA cm–2 with a low Tafel slope value (39.40 mV dec–1), which is much lower than its conventional RuO2 (401 mV), 20% Pt/C (566 mV), and PO-C nanosphere (452 mV) counterparts. Higher performance is attributed to the synergy between N and S in the NSPO-C nanospheres, which provides maximum exposure to electroactive sites, while special morphology ensures efficient pathways for fast charge transportation. These findings advocate that polyphosphazene-derived heteroatom-doped carbons are potential candidates to fabricate high-performance devices for water oxidation.

The current study aims to synthesize bimetal oxide nanoparticles (zinc and manganese ions) using the carica papaya leaf extract. The crystallite size of the nanoparticle from X-ray diffraction method was found to be 19.23 nm. The nanosheet morphology was established from Scanning Electron Microscopy. Energy-dispersive X-ray diffraction was used to determine the elemental content of the synthesized material. The atomic percentage of Mn and Zn was found to be 15.13 and 26.63. The weight percentage of Mn and Zn was found to be 7.08 and 10.40. From dynamic light scattering analysis, the hydrodynamic diameter and zeta potential was found to be 135.1 nm and −33.36 eV. The 1,1-diphenyl-2-picryl hydroxyl radical, hydroxyl radical, FRAP, and hydrogen peroxide scavenging tests were used to investigate the antioxidant activity of Mn-Zn NPs. Mn-Zn NPs have substantial antioxidant properties. The photocatalytic activity of the Mn-Zn NPs was assessed by their ability to degrade Erichrome black T (87.67%), methyl red dye (78.54%), and methyl orange dye (69.79%). Additionally, it had significant antimicrobial action S. typhi showed a higher zone of inhibition 14.3 ± 0.64 mm. Mn-Zn nanoparticles were utilized as a catalyst for p-nitrophenol reduction. The bimetal oxide Mn-Zn NPs synthesized using C. papaya leaf extract exhibited promising dye degradation activity in wastewater treatment. Thus, the aforementioned approach will be a novel, low cost and ecofriendly approach.