TY - JOUR
T1 - Surface disordered rutile TiO2-graphene quantum dot hybrids
T2 - a new multifunctional material with superior photocatalytic and biofilm eradication properties
AU - Biswas, Anupam
AU - Salunke, Gayatri
AU - Khandelwal, Puneet
AU - Das, Raja
AU - Poddar, Pankaj
N1 - Funding Information:
P. P. acknowledges the Centre for Excellence in Surface Science at the National Chemical Laboratory, network project Nano-Safety, Health & Environment (SHE) funded by the Council of Scientific and Industrial Research (CSIR), India, and the Department of Science & Technology (DST), India through an Indo-Israel grant to develop materials for solar-voltaic energy devices DST/INT/ISR/P-8/2011. A. B. and G. S. acknowledge Department of Science & Technology (DST), India (DST/INT/ISR/P-8/2011) for financial support. R. D. and P. K. acknowledge Council of Scientific and Industrial Research (CSIR), India and Department of Biotechnology (DBT), India for financial support, respectively.
Publisher Copyright:
© The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.
PY - 2017
Y1 - 2017
N2 - The controlled introduction of defects in semiconductors has contributed to the development of electronic devices and technologies. Recently, chemical control over defects, formation of new hybrid materials and multifunctional nanostructures have been sought in energy, health, and environment related technologies. Surface-disordered anatase-TiO2 has received wide attention due to its exceptional photocatalytic performance. Herein, we demonstrate, for the first time, a one-step aqueous-phase synthesis of a surface-disordered rutile TiO2-graphene quantum dot (TG) hybrid material. The TG-hybrid is a rutile-TiO2 matrix in which homogeneous in situ insertion of GQDs occurs during the growth of the TiO2 particles. The TG-hybrid material showed superior photocatalytic performance with ∼98% solar light driven photo-degradation of methylene blue (MB) dye within 6 min and ∼86% of rhodamine-B (RhB) within 4 min which is much better than the photocatalytic performance shown by the rutile-TiO2 (∼30% and ∼20%, respectively) and GQDs (∼15% and ∼8%, respectively), themselves. Moreover, the TG-hybrid also showed enhanced toxicity to Gram-positive (S. aureus) as well as Gram-negative (E. coli, P. aeruginosa) bacterial cells. The growth-curves of E. coli cells, after incubating them with increasing concentrations of the TG-hybrid, showed that the TG-hybrid could effectively inhibit the growth of E. coli cells at a concentration of 60 μg mL−1. The effect of UV-light exposure on the bacterial-biofilm disruption by the TG-hybrid material was also investigated. It was observed that in the presence of UV-light, the biofilm disruption done by the TG-hybrid was larger in comparison to the TiO2 and GQDs alone, under the same conditions. The increase in the formation of reactive oxygen species (ROS) in the presence of sunlight for the TG-hybrid may be the reason behind its superior antibacterial and biofilm eradication properties. We believe that the TG-hybrid material will have applications in energy, health and environment related technologies.
AB - The controlled introduction of defects in semiconductors has contributed to the development of electronic devices and technologies. Recently, chemical control over defects, formation of new hybrid materials and multifunctional nanostructures have been sought in energy, health, and environment related technologies. Surface-disordered anatase-TiO2 has received wide attention due to its exceptional photocatalytic performance. Herein, we demonstrate, for the first time, a one-step aqueous-phase synthesis of a surface-disordered rutile TiO2-graphene quantum dot (TG) hybrid material. The TG-hybrid is a rutile-TiO2 matrix in which homogeneous in situ insertion of GQDs occurs during the growth of the TiO2 particles. The TG-hybrid material showed superior photocatalytic performance with ∼98% solar light driven photo-degradation of methylene blue (MB) dye within 6 min and ∼86% of rhodamine-B (RhB) within 4 min which is much better than the photocatalytic performance shown by the rutile-TiO2 (∼30% and ∼20%, respectively) and GQDs (∼15% and ∼8%, respectively), themselves. Moreover, the TG-hybrid also showed enhanced toxicity to Gram-positive (S. aureus) as well as Gram-negative (E. coli, P. aeruginosa) bacterial cells. The growth-curves of E. coli cells, after incubating them with increasing concentrations of the TG-hybrid, showed that the TG-hybrid could effectively inhibit the growth of E. coli cells at a concentration of 60 μg mL−1. The effect of UV-light exposure on the bacterial-biofilm disruption by the TG-hybrid material was also investigated. It was observed that in the presence of UV-light, the biofilm disruption done by the TG-hybrid was larger in comparison to the TiO2 and GQDs alone, under the same conditions. The increase in the formation of reactive oxygen species (ROS) in the presence of sunlight for the TG-hybrid may be the reason behind its superior antibacterial and biofilm eradication properties. We believe that the TG-hybrid material will have applications in energy, health and environment related technologies.
UR - http://www.scopus.com/inward/record.url?scp=85016304301&partnerID=8YFLogxK
U2 - 10.1039/c6nj03607d
DO - 10.1039/c6nj03607d
M3 - Article
AN - SCOPUS:85016304301
VL - 41
SP - 2642
EP - 2657
JO - New Journal of Chemistry
JF - New Journal of Chemistry
SN - 1144-0546
IS - 7
ER -