Mechanism investigation for ultra-efficient photocatalytic water disinfection based on rational design of indirect Z-scheme heterojunction black phosphorus QDs/Cu2O nanoparticles

• Published in: Journal of hazardous materials Vol. 424; p. 127281
• Main Authors: Luo, Shijia, Liu, Ruixi, Zhang, Xixi, Chen, Rui, Yan, Mingming, Huang, Kerang, Sun, Jing, Wang, Rong, Wang, Jianlong
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.02.2022
• Subjects: Black phosphorus quantum dots; Indirect Z-scheme heterojunction; Methicillin-resistant Staphylococcus aureus; MOFs-derivatives; Photocatalytic inactivation; MOFs-derivatives; Photocatalytic inactivation; Black phosphorus quantum dots; Methicillin-resistant Staphylococcus aureus; Indirect Z-scheme heterojunction
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2021.127281

Photocatalysis has been regarded as a promising inactivation technology targeting to reduce drug-resistant bacteria contamination, but developing efficient photocatalysts with broad visible light harvesting capability is still a challenge. Here we report a MOFs-derived BPQDs/Cu2O/N-doped hollow porous carbon (BP/CNC) with indirect Z-scheme heterojunctions (BPQDs/Cu2O), which can inactivate 99.99999% Methicillin-resistant Staphylococcus aureus (MRSA) at a concentration of only 10 mg/L. Combining photoelectrochemical techniques and electrochemical measurements, the efficient inactivation process was attributed to the synergistic effect of enhanced light utilization and effective suppression of photogenerated carrier recombination. The mechanism of gradually damaged cell membrane for MRSA was studied by employing scanning electron microscopy (SEM), fluorescence staining and coagulase titer test to further decipher the changes in bacterial cells. We propose that reactive oxygen species (ROS) destroys the cell wall membrane and causes the leakage of cell contents, eventually leading to death. In addition, a series of in vitro and in vivo toxicity tests were conducted to evaluate the biocompatibility of the antibacterial system and its potential use in practice. This strategy of BPQDs/Cu2O indirect heterojunction fabrication can spatially inhibit the recombination of photogenerated carriers, expands the light absorption range, providing a feasible method for disinfecting microbial contaminated water. [Display omitted] •Superior photocatalytic activity of BP/CNC for inactivating resistant bacteria.•A method to construct a none-noble metal indirect Z-scheme heterojunction.•The hollow porous structure effectively extends the light path to improve light utilization.•Good biocompatibility makes BP/CNC have the potential for practical application.