Biomolecule-free, selective detection of o-diphenol and its derivatives with WS2/TiO2-based photoelectrochemical platform

Herein, a novel photoelectrochemical platform with WS2/TiO2 composites as optoelectronic materials was designed for selective detection of o-diphenol and its derivatives without any biomolecule auxiliary. First, catechol was chosen as a model compound for the discrimination from resorcinol and hydroquinone; then several o-diphenol derivatives such as dopamine, caffeic acid, and catechin were also detected by employing this proposed photoelectrochemical sensor. Finally, the mechanism of such a selective detection has been elaborately explored. The excellent selectivity and high sensitivity should be attributed to two aspects: (i) chelate effect of adjacent double oxygen atoms in the o-diphenol with the Ti(IV) surface site to form a five/six-atom ring structure, which is considered as the key point for distinction and selective detection. (ii) This selected WS2/TiO2 composites with proper band level between WS2 and TiO2, which could make the photogenerated electron and hole easily separated and results in great improvement of sensitivity. By employing such a photoelectrochemical platform, practical samples including commercial clinic drugs and human urine samples have been successfully performed for dopamine detection. This biomolecule-free WS2/TiO2 based photoelectrochemical platform demonstrates excellent stability, reproducibility, remarkably convenient, and cost-effective advantages, as well as low detection limit (e.g., 0.32 μmol L(-1) for dopamine). It holds great promise to be applied for detection of o-diphenol kind species in environment and food fields.

Ultrathin g-C3N4/TiO2composites as photoelectrochemical elements for the real-time evaluation of global antioxidant capacity

Using utg-C₃N₄/TiO₂, a photoelectrochemical platform was designed for the sensing of global antioxidant capacity, which presented a rapid response, and anti-fouling and colour-interference-proof properties.

Carbon Nanostructures for Enhanced Photocatalysis for Biocidal Applications

In the last few decades, the demand for safer environmental conditions has increased dramatically. The burden of infectious diseases worldwide, related to contamination via contact with contaminated surfaces (fomites), is a growing issue. Globally, these infections are linked to an estimated 1.7 million deaths a year from diarrheal disease and 1.5 million deaths from respiratory infections [1]. Apart from hospitals, the problem has become a growing liability at places where food is prepared and handled [2], where there is a growing risk associated with the cross-contamination of edible goods and where large amounts are handled by a single facility [3]. Already many E. coli and Salmonella outbreaks have been recorded and linked to single a facility [2, 4, 5]. The problem of cross-contamination via surfaces can also be traced, in smaller scale, to households where common areas can accumulate pathogens that can potentially become a threat, especially to more sensitive population groups [6]. There are also biological threats in forms of dangerous epidemic outbreaks (Ebola and SARS) and biological warfare weapons (anthrax and smallpox). The need for effective and efficient disinfection is driving the industry in the development of a wide range of products. These products can currently be divided into three major categories: