Photocatalytic production of chlorine dioxide using inexpensive reagents and semiconductor photocatalysts

Overview

Chlorine dioxide (ClO2) is a well-established, non-toxic antimicrobial molecule widely used for disinfection. This research proposes a photocatalytic approach to produce ClO2 on demand under ambient conditions using inexpensive reagents, specifically sodium chlorate (NaClO3) as the chlorine source. By leveraging semiconductor-based photocatalysts activated under UV and visible light, excited electrons with sufficient reducing power are generated to convert NaClO3 into ClO2. This method offers a potentially low-cost, light-driven alternative to conventional ClO2 production routes, enabling decentralized and sustainable generation of this important disinfectant for water treatment, food safety, healthcare, and other antimicrobial applications.

Technical specifications

Core approach:

• Uses NaClO3 as an inexpensive chlorine source for ClO2 production
• Semiconductor-based photocatalysts activated by UV and visible light irradiation
• Excited electrons with strong reducing potential drive the reduction of NaClO3 to ClO2
• Alcohols or oxalic acid serve as hole scavengers to sustain the photocatalytic cycle

Photocatalyst library and capabilities:

• Semiconductors with high-lying conduction bands are selected for adequate reduction power
• Composition, size, and thickness of semiconductors are tuned to optimize redox performance
• Established expertise synthesizing TiO2, carbon nitrides, CdS, ZnS, ZnIn2S4, and metal-organic frameworks
• Morphologies range from ultrathin nanosheets to quantum dots

Optimization parameters:

• Band structure modulation of semiconductors
• Co-catalyst design
• Irradiation wavelength and intensity tuning
• ClO2 yield quantified via UV-visible absorption spectroscopy

Technology readiness level

This is an early-stage research concept at Technology Readiness Level 1–2 (basic principle observed and technology concept formulated). The hypothesis has not yet been experimentally tested in the laboratory. The research group brings strong prior expertise in photocatalytic transformations and semiconductor photocatalyst synthesis, which supports confidence in feasibility. The planned validation pathway begins with measuring the reduction potential of NaClO3 under application-relevant conditions, followed by catalyst design and synthesis, ClO2 quantification, and systematic optimization of production rate. The laboratory is well equipped for both materials synthesis and photocatalytic studies, enabling rapid hypothesis testing.