Tanmay Ghosh

Developing plasmonic metal‐based electrocatalysts for selective and sensitive biomolecular sensing remains an important research focus. Herein, a facile non‐enzymatic electrochemical sensing platform based on Au@Ag _n core–shell nanocubes (NCs)‐modified glassy carbon electrode is reported for the simultaneous detection of three kidney dysfunction biomarkers (KDBs): creatinine (Crn), uric acid (UA), and xanthine (Xan). Among different shell thicknesses, Au@Ag ₃ NC exhibited superior electrocatalytic activity, showing well‐resolved diffusion‐controlled oxidation peaks, enhanced current response, interference‐free detection, and good long‐term stability. The enhanced catalytic performance is attributed to interfacial tensile strain and electronegativity differences between the Au core and Ag shell, generating a positively charged surface which is favorable for electron rich analyte adsorption. Density functional theory (DFT) calculations further revealed enhanced charge transfer between the adsorbates (KDBs) and Au@Ag _n NC surfaces with increasing Ag‐shell thickness, supporting the experimental observations. Differential pulse voltammetry (DPV) demonstrated a wide linear detection range from nM to mM concentrations with limits of detection (LOD) of 20.6, 28.0, and 34.3 nM for Crn, UA, and Xan, respectively. The proposed nanocatalytic platform also showed satisfactory recovery in human bio‐fluid analysis, highlighting its potential for multiplexed kidney biomarker sensing.

Tuning of catalyst-support interactions potentially offers a powerful means to control activity. However, rational design of the catalyst support is challenged by a lack of clear property-activity relationships. Here, we uncover how the electronegativity of a support influences reaction pathways in electrochemical CO ₂ reduction. This was achieved by creating a model system consisting of Cu nanoparticles hosted on a series of carbon supports, each with a different heteroatom dopant of varying electronegativity. Notably, we discovered that dopants with high electronegativity reduce the electron density on Cu and induce a selectivity shift toward multicarbon (C ₂₊ ) products. With this design principle, we built a composite Cu and F-doped carbon catalyst that achieves a C ₂₊ Faradaic efficiency of 82.5% at 400 mA cm ⁻² , with stable performance for 44 hours. Using simulated flue gas, the catalyst attains a C ₂₊ FE of 27.3%, which is a factor of 5.3 times higher than a reference Cu catalyst.

A hard and soft acid and base theory guided “ship-in-a-bottle” strategy to incorporate bismuth nanoparticles inside a thiol-rich MOF unlocking dual catalytic activities.

Rechargeable magnesium batteries (RMBs) are emerging as promising alternatives to lithium-ion batteries due to their high volumetric capacity and natural abundance. However, challenges arising from severe passivation and uneven deposition in conventional electrolytes persist, resulting in poor reversibility and cycling stability. Herein, a covalent molecule of 1-chloropropane (CP) is introduced into conventional electrolytes to manipulate the kinetics and surface chemistry of Mg anodes. Stemming from the reduced surface energy of the Mg (002) crystal plane from CP–Mg interactions, a horizontally arranged platelet morphology with enhanced (002) orientations is preferentially formed during the electrodeposition process. Moreover, the appropriate lowest unoccupied molecular orbital energy level of CP enables a robust Cl-rich interphase in situ formed on the Mg electrode surface. The planar deposition morphology coupled with the protective interphase can effectively suppress parasitic reactions between Mg electrodes and electrolytes and facilitate the electrochemical reaction kinetics. The as-designed electrolyte achieves reversible Mg plating/stripping with a high coulombic efficiency of 99.79% in asymmetric cells and maintains stable cycling for over 215 h in symmetric cells at an ultrahigh current density of 25 mA cm⁻², outperforming previously reported results. This engineered electrolyte also exhibits excellent compatibility with different inorganic/organic cathode materials, offering promising opportunities for RMB applications.

Nanoparticle (NP) catalysts are ubiquitous in energy systems, chemical production, and reducing the environmental impact of many industrial processes. Under reactive environments, the availability of catalytically active sites on the NP surface is determined by its dynamic structure. However, atomic-scale insights into how a NP surface reconstructs under reaction conditions and the impact of the reconstruction on catalytic activity are still lacking. Using operando transmission electron microscopy, we show that Pd NPs exhibit periodic round–to–flat transitions altering their facets during CO oxidation reaction at atmospheric pressure and elevated temperatures. This restructuring causes spontaneous oscillations in the conversion of CO to CO₂ under constant reaction conditions. Our study reveals that the oscillatory behavior stems from the CO-adsorption-mediated periodic restructuring of the nanocatalysts between high-index-faceted round and low-index-faceted flat shapes. These atomic-scale insights into the dynamic surface properties of NPs under reactive conditions play an important role in the design of high-performance catalysts.

Organic-inorganic metal halide perovskite films have emerged as potential candidate materials for photoelectric devices because of their superior optoelectronic properties. The performance of these devices depends on the quality of perovskite films defined by their grain size, crystallinity, and absence of pinholes. While solution-based processing is the most cost-effective and scalable approach to producing these films, the impact of the process parameters on the film quality and nanoscale details of these processes are unknown. Specifically, it is unclear how perovskites grow from a liquid precursor to form solid-phase nanocrystals and how these nanocrystals arrange to form a uniform film. Here, using liquid-phase transmission electron microscopy (TEM), we show how perovskite nanocrystals nucleate from a precursor solution and then grow and coalesce to form a polycrystalline film. Furthermore, we show how additives, such as urea, can improve the film crystallinity by increasing perovskite solubility, which induces the dissolution and subsequent redeposition of smaller crystals onto larger grains. Our approach to studying the growth of perovskite films provides an important insight into improving the synthesis of perovskites and other technologically relevant crystalline films.