Article
Chemistry, Multidisciplinary
Eero Hulkko, Tanja Lahtinen, Varpu Marjomaki, Emmi Pohjolainen, Ville Saarnio, Karolina Sokolowska, Ardra Ajitha, Mikael Kuisma, Lauri Lehtovaara, Gerrit Groenhof, Hannu Hakkinen, Mika Pettersson
Summary: The study investigated the interaction between an atomically precise gold nanocluster and a fluorescent organic dye molecule. By covalently linking the dye to the nanocluster, the hybrids could enter cells and release their cargo via hydrolysis of the ester bond. Changes in pH inside endosomes regulated reversible fluorescence, paving the way for future development of cluster-reporter sensors for in vivo measurements.
NANOSCALE ADVANCES
(2021)
Article
Chemistry, Analytical
Xue Hu, Xiaodan Zhang, Haiyan Cao, Yuming Huang
Summary: The study introduces a new strategy for preparing photoluminescent Cu NCs using Cu-MOFs as precursors, which can be applied in a ratiometric fluorescent sensing platform for pH detection. The Cu NCs exhibit unique pH-dependent photoluminescence property, offering potential for applications in bioassays and other fields.
SENSORS AND ACTUATORS B-CHEMICAL
(2022)
Article
Chemistry, Inorganic & Nuclear
Anish Kumar Das, Roopesh Mekkat, Subarna Maity, Akhil S. Nair, Subhrajyoti Bhandary, Rohit Bhowal, Amitava Patra, Biswarup Pathak, Deepak Chopra, Sukhendu Mandal
Summary: A series of face-centered cubic-based silver nanoclusters were studied by varying the halogen atom in the thiolate ligand to investigate the influence of halide atoms on the electronic structure. These clusters are emissive at room temperature, with luminescence intensity increasing as temperature decreases, predominantly originating from interband relaxation of the silver cores.
INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Inorganic & Nuclear
Anish Kumar Das, Roopesh Mekkat, Subarna Maity, Akhil S. Nair, Subhrajyoti Bhandary, Rohit Bhowal, Amitava Patra, Biswarup Pathak, Deepak Chopra, Sukhendu Mandal
Summary: The structure-property correlation of a series of silver nanoclusters reveals a strong relationship between the optical and electrochemical bandgap values and the electronic effect of halides, governed by intracluster and intercluster pi-pi interactions. Emission from these clusters at room temperature is predominantly due to interband relaxation of the Ag cores, with femtosecond transient absorption spectra showing decay profiles dominated by relaxation to surface states. This sheds light on the molecular-like dynamics of these nanoclusters with a face-centered cubic core.
INORGANIC CHEMISTRY
(2021)
Article
Spectroscopy
Miao An, Hui Li, Ming Su, Shu Gao, Ming Chen Wang, Shi Gang Shen, Zhong Feng Gao, Jiang Xue Dong
Summary: A water-soluble fluorescent Ag nanoclusters (DPA@Ag NCs) were prepared using D-Penicillamine as a stabilizer, and the fluorescence quantum yield was enhanced fourfold by doping with Cu2+ to create DPA@Ag/Cu NCs. This enhancement was attributed to changes in the self-assembly structures of the nanoclusters induced by Cu2+. A highly sensitive and selective Ag+ sensor was developed based on these nanoclusters, with a linear relationship between fluorescence intensity quenching and Ag+ concentration in the range of 0.05-800 mu M, and a detection limit of 0.03 mu M.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2021)
Article
Chemistry, Analytical
Shanshan Liu, Nian Wang, Li Li, Yi Liu
Summary: In this study, a signal-on fluorescence biosensing platform based on self-assembled aggregation-induced emission fluorochrome ZIF-8@EBTAC was developed for the detection of alkaline phosphatase. The biosensor showed excellent performance in monitoring ALP activity with a detection limit of 0.01 U L-1, using pyrophosphate as a substrate.
ANALYTICAL METHODS
(2023)
Article
Chemistry, Physical
Jin Li, Xiao-Peng Liu, Wen-Qi Ye, Zhang-Run Xu
Summary: A novel photothermal quantitative method based on the etching of MnO2-coated gold nanoparticles was developed for the determination of alkaline phosphatase (ALP) activity using a household thermometer as a visual readout. The photothermal effect of the nanoparticles was significantly enhanced by the MnO2 shell, and the etching of the nanoparticles caused a gradual decrease in the temperature increment of the solution. The method showed a wide linear range and a low detection limit, and could potentially be applied for screening enzyme inhibitors.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2023)
Article
Engineering, Environmental
Zhongnan Huang, Zhenglian Li, Zhimin Weng, Paramasivam Balasubramanian, Mingchun Lai, Wei Chen, Juewen Liu, Huaping Peng
Summary: In this study, a model system was developed to evaluate the effect of electrocatalysis (EC) on electrochemiluminescence (ECL) through kinetic analysis of electrocatalytic reactions. The results demonstrated a dual EC-mediated ECL enhancement and identified the catalytically active sites. With a better understanding of the EC mechanism, the researchers successfully used EC to regulate ECL and developed a biosensor with a record low limit of detection.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Physical
Debkumar Bera, Mousumi Baruah, Asish K. Dehury, Animesh Samanta, Yatendra S. Chaudhary, Nirmal Goswami
Summary: Nanoscale assembly of ultrasmall metal nanoclusters using molecular forces has been shown to be a powerful strategy to manipulate their properties in various dimensions. In this study, we demonstrate the formation of kinetically trapped assemblies with enhanced photoluminescence and extended this principle to other materials. We also show a thermal energy driven process to isolate these assemblies, which exhibit thermodynamic stability and unique properties. Our strategy may have broader applications in creating different MNC-based assemblies with unforeseen arrangements and properties.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Chemistry, Applied
Zheng-Fen Pu, Jun Peng, Qiu-Lin Wen, Yu Li, Jian Ling, Peng Liu, Qiu-E Cao
Summary: A new photocatalytic synthesis strategy was developed for the rapid preparation of BSA-Au nanoclusters with tunable fluorescence, which could be used for highly selective detection of silver ions. The silver ion not only acted as a photocatalyst to accelerate the formation of fluorescent Au nanoclusters, but also as a regulator to tune the fluorescence emission color of the BSA-Au nanoclusters. This method showed high selectivity for silver ion detection and had potential applications in environmental water sample analysis.
Article
Chemistry, Analytical
Bo Fu, Xinyu Zheng, Huihui Li, Lu Ding, Fuxiang Wang, Dong-Yu Guo, Weiting Yang, Qinhe Pan
Summary: This study developed a fluorescent probe for highly stable, rapid, and sensitive determination of CIP through Al3+-enhanced fluorescence of gold nanoclusters, exhibiting ratiometric response and the ability to avoid analyte-independent interference.
SENSORS AND ACTUATORS B-CHEMICAL
(2021)
Article
Chemistry, Multidisciplinary
Yu-Jin Kong, Jia-Hua Hu, Xi-Yan Dong, Yubing Si, Zhao-Yang Wang, Xi-Ming Luo, Hong-Ren Li, Zongwei Chen, Shuang-Quan Zang, Thomas C. W. Mak
Summary: Understanding the contributions of chiral and achiral sections in chiral nanostructures to circularly polarized light emission (CPLE) is fundamentally important. This study investigates the effects of homochiral and heterochiral structures on CPLE using two pairs of atomically precise enantiomers. The findings reveal that the metal bonding in the heterochiral structure activates CPLE by altering the delocalization of orbitals and the proportion of achiral and chiral sections in electron transition-involved orbitals, providing new insights for the development of CPLE nanoparticles.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Nanoscience & Nanotechnology
Qiming Shen, Faisal Hossain, Changhao Fang, Tong Shu, Xueji Zhang, John Lok Man Law, Michael Logan, Michael Houghton, D. Lorne Tyrrell, Michael A. Joyce, Michael J. Serpe
Summary: This study developed an approach to assess SARS-CoV-2 infection. The virus nucleocapsid protein (NP) was targeted for virus detection. Antibodies were immobilized on magnetic beads to capture the NPs, which were then detected using specific antibodies and alkaline phosphatase. This assay showed high sensitivity and reliability, with a relatively short detection time.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Inorganic & Nuclear
Jin Wu, Ning Chen, Tao Wu
Summary: In this study, two discrete dimeric metal-chalcogenide supertetrahedral clusters were prepared via solvothermal reactions. The crystal structures, optical, and electrical properties of these compounds were also investigated.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Physical
Gyongyi Gombar, Peter Simon, Ditta Ungor, Istvan Szatmari, Edit Csapo
Summary: A new biomolecule, HisHA, is demonstrated to produce few-atomic fluorescent gold nanoclusters (Au NCs) in water. The preparation protocol is optimized by studying various factors, and the role of citrate as a reducing agent is explored. The stability of these NCs under high salt concentration and their ability to detect metal ions (copper and zinc) is confirmed.
JOURNAL OF MOLECULAR LIQUIDS
(2023)
Article
Chemistry, Physical
Sikta Chakraborty, Dipankar Bain, Subarna Maity, Sarita Kolay, Amitava Patra
Summary: In this study, bimetallic AuCu nanoclusters were synthesized and their aggregation-induced emission (AIE) was investigated. The emission band of Au NCs showed a significant blue shift with changes in the Au/Cu molar ratio, and a significant enhancement in emission intensity was observed at lower temperatures. Aggregation of the ultrasmall-sized AuCu NCs in a less polar medium resulted in a 200-fold increase in emission intensity. Metal cluster-based AIE-type materials offer a promising approach for designing highly luminescent materials for various applications.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Multidisciplinary
Dipankar Bain, Aarti Devi, Sikta Chakraborty, Amitava Patra
Summary: We designed a fluorescent probe, poly(allylamine) hydrochloride (PAH) functionalized copper nanocluster (Cu NC@PAH), for the selective detection of sulfide (S2-) ions in water. The probe showed a significant enhancement in photoluminescence (PL) intensity and quantum yield (QY) after functionalizing with the cationic polymer PAH. The probe also exhibited excellent selectivity and a reasonable quenching response for S2- ions, with a detection limit of 2.39 μM.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2023)
Article
Chemistry, Physical
Srijon Ghosh, Kritiman Marjit, Goutam Ghosh, Debarati Ghosh, Amitava Patra
Summary: This study investigates the photoinduced energy and electron transfer processes between quaterthiophene (QTH) and squaraine (SQR) dye in hybrid aggregates. The results show that energy transfer from QTH aggregates to SQR aggregates occurs within 120 fs, while electron transfer occurs at timescales of 131.5 ps and 3.3 ns, leading to the formation of a long-lived charge-separated state for more than 8 ns.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Goutam Ghosh, Kritiman Marjit, Srijon Ghosh, Amitava Patra
Summary: We investigate the fast hot-carrier (HC) relaxation and Auger recombination (AR) rates in hexapod CsPbBr3 NCs using ultrafast transient absorption (TA) spectroscopy. Our results show that hexapod CsPbBr3 has a prolonged HC cooling time and bi-exciton lifetime compared to cubic CsPbBr3. By employing the electron-phonon coupling model, we confirm the slower HC relaxation rate in hexapod CsPbBr3, suggesting a delayed decay of longitudinal optical (LO) phonons. We demonstrate that delocalization of charge carriers in shallow trap states leads to reduced overlap of electron and hole wave functions and suppresses the bi-exciton AR rate.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Sarita Kolay, Subarna Maity, Sikta Chakraborty, Srijon Ghosh, Amitava Patra
Summary: This work investigates the impact of substituent groups on the relaxation dynamics of atomically precise Ag44(SR)304- nanoclusters. The electronegativity and polarization of the surface ligands are found to control the electron-phonon interaction, affecting the population transfer within the nanoclusters upon photoexcitation. Transient absorption spectroscopic data analysis reveals a slower relaxation process from the core state to the surface state, depending on the electronegativity. The ligand-protected Ag44 nanoclusters exhibit fast internal conversion, core-to-surface relaxation, and slower electron-hole recombination.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Multidisciplinary
Lipipuspa Sahoo, Aarti Devi, Amitava Patra
Summary: The generation of green hydrogen through electrocatalytic water splitting is a promising approach for future energy devices. In this study, a water-soluble, atomically precise Ni nanocluster (NC)-modified MoSe2 nanosheet (NS) catalyst was developed to enhance the hydrogen evolution reaction (HER) performance. The Ni/MoSe2 nanocomposite exhibited significantly improved HER efficiency, with an overpotential of 170 mV @ 10 mA/cm2, compared to bare MoSe2 NSs (350 mV). The incorporation of Ni NCs accelerated the HER kinetics of MoSe2, as indicated by the lower Tafel slope and reduced charge-transfer resistance in the nanocomposite. This work highlights the potential of combining non-precious metal NCs and transition-metal dichalcogenides to design efficient and cost-effective electrocatalysts for HER.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2023)
Article
Nanoscience & Nanotechnology
Debarati Ghosh, Monojit Ghosal Chowdhury, Rathindranath Biswas, Krishna Kanta Haldar, Amitava Patra
Summary: In this study, a nanocomposite containing europium molybdate and molybdenum disulfide was synthesized in situ for enhanced electrochemical hydrogen evolution reaction (HER). The nanoflower architecture of MoS2 coupled with flakes of europium molybdate was observed, leading to an enhanced surface area and improved HER activity. The fabrication of lanthanide-containing MoS2 nanocomposites shows promise for efficient electrocatalytic hydrogen generation.
ACS APPLIED NANO MATERIALS
(2023)
Article
Chemistry, Physical
Kritiman Marjit, Goutam Ghosh, Srijon Ghosh, Debarati Ghosh, Anusri Medda, Amitava Patra
Summary: In this study, the electron transfer dynamics in the CsPbBr3-Au-144 cluster hybrid system were investigated using ultrafast transient absorption spectroscopy. The results showed faster hot carrier cooling time and a significant drop in hot carrier temperature, indicating hot electron transfer from CsPbBr3 nanocrystals to Au nanoclusters. Furthermore, a much faster hot electron transfer compared to band-edge electron transfer was observed, and a 45% hot-electron transfer efficiency was achieved at energy above the band-edge excitation. The significant enhancement of the photocurrent to the dark current ratio confirmed the charge separation via electron transfer in this hybrid system.
ACS PHYSICAL CHEMISTRY AU
(2023)
Article
Chemistry, Multidisciplinary
Anusri Medda, Soubhik Ghosh, Amitava Patra
Summary: Transition metal-doped two-dimensional semiconductor nanoplatelets (NPLs) have been synthesized and investigated, showing improved charge carrier separation and efficient performance as photodetectors.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Physical
Igor M. Goncalves, Anusri Medda, Alyson J. A. Carvalho, Ceciilia L. A. V. Campos, Soubhik Ghosh, Anderson S. L. Gomes, Amitava Patra
Summary: The nonlinear optical response of CdSe and CdSe/CdS core/shell nanoplatelets in toluene suspension was studied using Z-scan and optical Kerr gate techniques. The Z-scan analysis yielded nonlinear coefficients of n(2) = 1.4 x 10(-16) cm(2)/W and n(2) = 1.3 x 10(-16) cm(2)/W for CdSe and CdSe/CdS NPLs, respectively. The dominant behavior was fifth-order nonlinear absorption, with alpha(4) = 4.0 x 10(-2) cm/GW for CdSe NPLs and alpha(4) = 9.0 x 10(-3) cm/GW for CdSe/CdS NPLs. The results from Z-scan and optical Kerr gate were in good agreement, and the response time from OKG was less than 1 ps for all materials. NLA was observed for CdSe and CdSe/CdS NPLs but not for toluene, indicating that the presence of NPLs reduces the threshold of absorptive nonlinearity. The electronic structure of the materials was discussed to explain the results.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Antika Das, Kritiman Marjit, Srijon Ghosh, Debarati Ghosh, Amitava Patra
Summary: Lead halide perovskite nanocrystals (NCs) are advanced semiconductor materials for optoelectronic device development. Delaying the relaxation time of hot carriers (HCs) can enhance solar conversion efficiency. In this study, the surface of CsPbX3 (X = Br/Cl) NCs was treated with hexadecylamine (HDA) molecules, and femtosecond transient absorption spectroscopy was used to analyze the HC relaxation dynamics and ultrafast carrier dynamics. The results show faster ultrafast carrier relaxation with increasing Cl content in CsPbX3 NCs (X = Br/Cl). HDA-passivated CsPbX3 (X = Br/Cl) NCs exhibit slower ultrafast carrier relaxation and longer HC relaxation time compared to pristine NCs. Understanding the charge-carrier relaxation dynamics in CsPbX3 (X = Br/Cl) NCs can aid in the design of efficient optoelectronic devices.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Aarti Devi, Harshita Seksaria, Dipankar Bain, Sarita Kolay, Rashi, Abir De Sarkar, Amitava Patra
Summary: In this study, gold-copper bimetallic nanoclusters (AuCu NCs) were synthesized using a one-step co-reduction method. The emission wavelength of the NCs was tuned from 520 nm to 620 nm by changing the [Cu2+]/[Au3+] molar ratio. The quantum yield increased from 6% to 13% upon incorporation of Cu atoms. The composition of the Au NCs was determined to be Au-6(MPA)(5), while the bimetallic nanocluster was Au4Cu2(MPA)(5).
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Sarita Kolay, Subarna Maity, Sikta Chakraborty, Srijon Ghosh, Amitava Patra
Summary: This study reveals the influence of substituent groups on the relaxation dynamics of atomically precise Ag-44(SR)(30)(4-) nanoclusters. It shows that the electronegativity and polarization of surface ligands control the electron-phonon interaction and the population transfer from the core state to the surface state. The analysis of transient absorption spectroscopic data reveals the slower relaxation from the core state to the surface state depending on electronegativity and provides insights into the excited-state decay times of Ag-44 nanoclusters.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Kritiman Marjit, Anita Gemmy Francis, Swapan K. Pati, Amitava Patra
Summary: This study investigates the significance of dielectric confinements and exciton binding energy in controlling the carrier relaxation dynamics of hybrid layered perovskites (LPs). It is found that LPs with larger dielectric confinement and higher exciton binding energy exhibit faster carrier relaxation dynamics.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Physical
Debarati Ghosh, Kritiman Marjit, Goutam Ghosh, Srijon Ghosh, Amitava Patra
Summary: This study investigates the impact of bifunctional short-chain aromatic ligands on the charge transfer dynamics of 2D Ruddlesden Popper perovskites. Ultrafast transient absorption spectroscopy reveals evident electron transfer and hole transfer with different ligands, occurring in 900 fs and 1.9 ps, respectively. These findings provide insights for understanding the charge transfer dynamics in 2D Ruddlesden Popper perovskites, which will enhance the performance of next-generation optoelectronic devices.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)