Photocatalytic Applications of Red Phosphorus in Environmental Remediation

Red phosphorus has emerged as an elemental, metal-free photocatalyst capable of harvesting visible light to drive a range of environmental remediation processes. Its inherently narrow band gap (≈2.0 eV), chemical stability and low cost render it ideal for applications such as organic pollutant degradation, heavy-metal reduction and microbial disinfection in aqueous media. By forming heterojunctions with semiconductors or carbon-based frameworks, red phosphorus can substantially improve charge-carrier separation and extend light absorption into the visible spectrum. Such composites facilitate the production of reactive oxygen species (ROS) under solar irradiation, promoting oxidative breakdown of contaminants and reduction of toxic ions. Advances in material design—spanning simple thermal treatments, surface modifications and single-atom anchoring—have enhanced photocatalytic efficiency, reusability and selectivity. These developments portend scalable, sustainable approaches to water treatment, soil detoxification and air purification that address global pollution challenges.

Research from Nature Portfolio

Recent studies have demonstrated that red phosphorus can be integrated with graphitic carbon nitride to yield RPh–g-C₃N₄ heterostructures with superior photocatalytic performance. A facile, low-temperature synthesis disperses elemental red phosphorus within a nitrogen-rich framework, producing a composite with a narrowed effective band gap and increased surface area. Under visible-light irradiation, this heterostructure exhibits dramatically enhanced degradation rates of model organic dyes compared with bare constituents. Photoelectrochemical measurements reveal higher photocurrent densities and robust cyclic stability, attributable to efficient charge-carrier separation at the RPh–g-C₃N₄ interface and the capacitive behaviour of red phosphorus. This work establishes a template for designing metal-free photocatalysts that combine strong light absorption with long-term operational durability.

Photocatalytic Applications of Red Phosphorus in Environmental Remediation publication trend

The graph below shows the total number of articles in photocatalytic applications of red phosphorus in environmental remediation across all publications each year (not limited to Nature Index journals).

Technical terms

Photocatalyst: A material that absorbs light to generate electron–hole pairs, driving chemical reactions without being consumed.

Band gap: The energy difference between the valence and conduction bands; determines the wavelengths of light a semiconductor can absorb.

Heterojunction: An interface formed between two distinct semiconductors or materials, which facilitates efficient charge separation.

Reactive oxygen species (ROS): Highly reactive molecules (such as •OH and O₂•–) produced under illumination that oxidise pollutants or pathogens.

Charge‐carrier recombination: The process by which photogenerated electrons and holes reunite, reducing photocatalytic efficiency.

References

1. Facile and Scale Up Synthesis of Red Phosphorus-Graphitic Carbon Nitride Heterostructures for Energy and Environment Applications. Scientific Reports (2016).
2. Evaluation of photocatalytic activity of commercial red phosphorus towards the disinfection of E. coli and reduction of Cr (VI) under direct sunlight. Materials Research Express (2020).
3. Fabrication of ZnO/Red Phosphorus Heterostructure for Effective Photocatalytic H2 Evolution from Water Splitting. Nanomaterials (2018).