Publications
Dalton Trans., 2022, 51, 8160-8168
Chandan Das, Jagrit Grover, Tannu, Ayon Das, Debabrata Maiti *, Arnab Dutta * and Goutam Kumar Lahiri *
Abstract
Our modern civilization is currently standing at a crossroads due to excessive emission of anthropogenic CO2 leading to adverse climate change effects. Hence, a proper CO2 management strategy, including appropriate CO2 capture, utilization, and storage (CCUS), has become a prime concern globally. On the other hand, C1 chemicals such as methanol (CH3OH) and formic acid (HCOOH) have emerged as leading materials for a wide range of applications in various industries, including chemical, biochemical, pharmaceutical, agrochemical, and even energy sectors. Hence, there is a concerted effort to bridge the gap between CO2 management and methanol/formic acid production by employing CO2 as a C1-synthon. CO2 hydrogenation to methanol and formic acid has emerged as one of the primary routes for directly converting CO2 to a copious amount of methanol and formate, which is typically catalyzed by transition metal complexes. In this frontier article, we have primarily discussed the abundant first-row transition metal-driven hydrogenation reaction that has exhibited a significant surge in activity over the past few years. We have also highlighted the potential future direction of the research while incorporating a comparative analysis for the competitive second and third-row transition metal-based hydrogenation.
J. Chem. Phys. 159, 234703 (2023)
Insight into the photocatalytic and photothermal effect in plasmon-enhanced water oxidation property of AuTNP@ MnOx core–shell nanoconstruct
Diptiranjan Paital, Tarun Bansal, Tannu Kaushik, Gayatri Joshi, Soumyadip Sett, and Saumyakanti Khatua*
ABSTRACT
The development of robust and efficient photocatalytic constructs for boosting the water oxidation reaction (WOR) is needed for establishing a sunlight-driven renewable energy infrastructure. Here, we synthesized plasmonic core–shell nanoconstructs consisting of triangulargold nanoprism (AuTNP) core with mixed manganese oxide (MnOx) shell for photoelectrocatalytic WOR. These constructs show electrocatalytic WOR with a low onset overpotential requirement of 270 mV at pH 10. Photoexcitation showed further enhancement of theircatalytic activity resulting in ∼15% decrease of the onset overpotential requirement along with the generation of photocurrent density ofup to 300 μA/cm2. We showed that such light-driven enhancement of AuTNP@MnOx dyad’s catalytic activity toward the WOR processincludes contributions from both photocatalytic (hot carriers driven) and photothermal effects with photothermal effect playing the majorrole for wavelength between 532 and 808 nm. The contribution from the photocatalytic effect is appreciable only for high-energy excitationsnear the interband region, while the photothermal effect largely dominates for lower energy excitations near the LSPR wavelengths of the dyad.
Environ. Sci.: Water Res. Technol., 2023, 9, 2219-2225.​​
Deploying a molecular copper catalyst for efficient degradation of commercial and industrial dyes under practical conditions
A. Ali, B. V. Meena, N. A. Shah, Tannu, T. Dolkar, C. Ghoroi*, A. Dutta*,
Abstract
Water pollution due to the discharge of inadequately treated contaminated water from industry creates an ecological imbalance posing several health hazards leading to the depletion of aquatic flora and fauna. Therefore, an immediate solution pertaining to stringent action and awareness is warranted to preserve natural water bodies from industrial effluent. Here, we report a two-step method for wastewater treatment, wherein the first step deploys an adsorption-based dye-treatment method (coagulation and flocculation). In contrast, the second step enforces chemical oxidation induced via a combination of a bio-inspired molecular copper complex and H2O2. This catalytic unit efficiently degrades a versatile array of toxic industrial dyes, with varying molecular templates, present in aqueous solution at room temperature. The dye treatment process was primarily monitored via optical spectroscopy as decolouration of the solution indicated oxidative degradation of the dye molecules. A complementary gas chromatography experiment established that CO2 gas is produced as the major product of this process. Detailed mechanistic studies revealed that the chemical process proceeds via the formation of a Cu(III)-hydroxo intermediate, which actively destroys the aromatic backbone of the dyes without following traditional radical-based Fenton's chemistry. This two-step process was active over a broad pH range (pH 3–11) of aqueous solutions, while it exhibited excellent efficiency even during the degradation of actual industrial dyes in their original form without any pre-treatment. The capability of this dye-treatment process was successfully tested at 100 liter scale with industrial dyes, showcasing the high technology readiness level (TRL) of this process.
Exploring the hydrogen evolution reaction (HER) side of perovskite-based materials during photoelectrochemical water splitting
S.K. Tarik Aziz, Anwesha Banerjee, Tannu Kaushik, Sukanta Saha,and Arnab Dutta*
Book: SOLAR-DRIVEN GREEN HYDROGENGENERATIONAND STORAGE