TY - JOUR
T1 - Gold nanoparticles decorated two-dimensional TiO2 nanosheets as effective catalyst for nitroarenes and rhodamine B dye reduction in batch and continuous flow methods
AU - Shanmugaraj, Krishnamoorthy
AU - Mangalaraja, Ramalinga Viswanathan
AU - Campos, Cristian H.
AU - Pratap Singh, Dinesh
AU - Aepuru, Radhamanohar
AU - Thirumurugan, Arun
AU - Gracia-Pinilla, M. A.
AU - Shaji, Sadasivan
N1 - Publisher Copyright:
© 2023 Elsevier B.V.
PY - 2023/3
Y1 - 2023/3
N2 - Our environment is greatly endangered by the accumulation of various toxic organic pollutants that are continually produced through unavoidable human needs and the industrialization process. Herein, we report highly active gold nanoparticles (AuNPs) immobilized on two-dimensional (2D) TiO2 nanosheets (AuNPs-TiO2NSs) as a catalyst for the catalytic reduction of nitroarenes (NAs) such as 4-nitroaniline (4-NA), 4-(4-nitrophenyl)morpholine (4-NM), 4-(2-fluoro-4-nitrophenyl)morpholine (4-FNM) and rhodamine B (RhB) dye in the presence of sodium borohydride (NaBH4) medium. Initially, TiO2NSs are prepared by the hydrothermal treatment followed by the modification with 3-aminopropyl-trimethoxysilane (APTMS) coupling agent for strong anchoring of the AuNPs. HR-TEM images exhibit that AuNPs (2.30 ± 0.06 nm) are immobilized on the surface of ultrathin 2-dimensional TiO2NSs. AuNPs-TiO2NSs catalyst shows excellent catalytic activity towards the reduction of various NAs (4-NA, 4-NM and 4-FNM) and RhB dye with maximum conversion efficiency of >98 %. Moreover, the pseudo-first-order rate constants are estimated as 5.50 × 10−3 s−1, 7.20 × 10−3 s−1, 6.40 × 10−3 s−1 and 4.30 × 10−3 s−1 for the reduction of 4-NA, 4-NM, 4-FNM, and RhB, respectively. For large-scale industrial applications, AuNPs-TiO2NSs catalyst embedded in a continuous flow-fixed bed reactor for the catalytic reduction of 4-NA and RhB dye under optimized reaction conditions. AuNPs-TiO2NSs catalyst shows high conversion rates for 4-NA (>99 %) and RhB (>99%) along with excellent recyclability over 12 cycles in continuous flow fixed bed reactor. The mechanism of synthetic pathway and catalytic reduction of NAs and RhB dye over AuNPs-TiO2NSs catalyst are also proposed. This study may lead to the use AuNPs-TiO2NSs catalyst with superior recyclable catalytic efficiency in various catalytic reactions.
AB - Our environment is greatly endangered by the accumulation of various toxic organic pollutants that are continually produced through unavoidable human needs and the industrialization process. Herein, we report highly active gold nanoparticles (AuNPs) immobilized on two-dimensional (2D) TiO2 nanosheets (AuNPs-TiO2NSs) as a catalyst for the catalytic reduction of nitroarenes (NAs) such as 4-nitroaniline (4-NA), 4-(4-nitrophenyl)morpholine (4-NM), 4-(2-fluoro-4-nitrophenyl)morpholine (4-FNM) and rhodamine B (RhB) dye in the presence of sodium borohydride (NaBH4) medium. Initially, TiO2NSs are prepared by the hydrothermal treatment followed by the modification with 3-aminopropyl-trimethoxysilane (APTMS) coupling agent for strong anchoring of the AuNPs. HR-TEM images exhibit that AuNPs (2.30 ± 0.06 nm) are immobilized on the surface of ultrathin 2-dimensional TiO2NSs. AuNPs-TiO2NSs catalyst shows excellent catalytic activity towards the reduction of various NAs (4-NA, 4-NM and 4-FNM) and RhB dye with maximum conversion efficiency of >98 %. Moreover, the pseudo-first-order rate constants are estimated as 5.50 × 10−3 s−1, 7.20 × 10−3 s−1, 6.40 × 10−3 s−1 and 4.30 × 10−3 s−1 for the reduction of 4-NA, 4-NM, 4-FNM, and RhB, respectively. For large-scale industrial applications, AuNPs-TiO2NSs catalyst embedded in a continuous flow-fixed bed reactor for the catalytic reduction of 4-NA and RhB dye under optimized reaction conditions. AuNPs-TiO2NSs catalyst shows high conversion rates for 4-NA (>99 %) and RhB (>99%) along with excellent recyclability over 12 cycles in continuous flow fixed bed reactor. The mechanism of synthetic pathway and catalytic reduction of NAs and RhB dye over AuNPs-TiO2NSs catalyst are also proposed. This study may lead to the use AuNPs-TiO2NSs catalyst with superior recyclable catalytic efficiency in various catalytic reactions.
KW - Catalytic reduction
KW - Fixed bed reactor
KW - Gold nanoparticles modified TiO nanosheets
KW - Nitroarenes
KW - Rate constant
KW - Rhodamine B
UR - http://www.scopus.com/inward/record.url?scp=85146469003&partnerID=8YFLogxK
U2 - 10.1016/j.inoche.2023.110406
DO - 10.1016/j.inoche.2023.110406
M3 - Article
AN - SCOPUS:85146469003
SN - 1387-7003
VL - 149
JO - Inorganic Chemistry Communications
JF - Inorganic Chemistry Communications
M1 - 110406
ER -