Browsing by Author "Basu, Mrinmoyee"

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2D Nanostructures of CoFe2O4 and NiFe2O4: Efficient Oxygen Evolution Catalyst
(Elsiever, 2018-05-20) Basu, Mrinmoyee
Development of cost-effective, efficient electrocatalyst for oxygen evolution reaction (OER) is a challenging issue as OER has sluggish reaction kinetics due to transfer of multi-electrons. In this study, a new strategy has been developed for the synthesis of 2D nanostructures of CoFe2O4 and NiFe2O4 following a wet-chemical route followed by calcination. Following this method nanoplates of CoFe2O4 and nanosheets of NiFe2O4 have been successfully synthesized. These interconnected 2D structures are very efficient for oxygen evolution reaction and it is observed that CoFe2O4 nanoplates and NiFe2O4 nanosheets are catalytically more active compared to nanocubes and nanobipyramids of CoFe2O4 and NiFe2O4. CoFe2O4 nanoplates require only 1.64 V vs. RHE for generating current density of 10 mA/cm2 whereas nanocubes of CoFe2O4 require 1.68 V vs. RHE. Similarly, NiFe2O4 nanosheets require 1.69 V to generate current density 10 mA/cm2 and NiFe2O4 nanobipyramids require 1.77 V vs. RHE to engender 10 mA/cm2 current density. 2D sheet or Plate-like structure with more exposed surface atoms faces more electrolyte to adsorb and react which results in higher electrocatalytic activity.
2D Thin Sheet Heterostructures of MoS2 on MoSe2 as Efficient Electrocatalyst for Hydrogen Evolution Reaction in Wide pH Range
(ACS, 2020-03-09) Basu, Mrinmoyee
Two-dimensional layered transition metal dichalcogenides, MoSe2 and MoS2, have drawn potential attention in the field of water splitting. Coupling of MoS2 and MoSe2 provides a sustainable route to improve the electrocatalytic activity for the hydrogen evolution reaction (HER). Here, the heterostructures of thin sheets (ts) of MoSe2 and MoS2 are combined to develop the MoSe2-ts@MoS2-ts heterostructure via multiple-step methodology. First, thin sheets of MoSe2 are synthesized following the stepwise hydrothermal method. After the successful synthesis of MoSe2-ts, MoS2-ts is synthesized on it to develop the heterostructure: MoSe2-ts@MoS2-ts. By tuning the amount of MoS2-ts and MoSe2-ts in the heterostructure separately, the optimum condition is obtained for HER. The unique heterostructure is efficient for HER under wide pH conditions like 1 M KOH, pH-7 phosphate buffer, 3.5% saline water, and finally 0.5 M H2SO4. MoSe2-ts@MoS2-ts can generate 10 mA/cm2 current density under the application of −0.186 V vs RHE with a low Tafel value of 71 mV/decade. The formation of the heterojunction plays an essential role in facilitating charge transportation. Furthermore, the heterostructure provides the more active sites for the adsorption of hydrogen to generate H2. An excess amount of any of the bare counter parts in the heterostructure leads to a decrease in electrocatalytic efficiency because of the lowered heterojuction formation. MoSe2-ts@MoS2-ts has very high stability during the electrocatalytic reaction, which is determined from 1000 consecutive cycles and a 24 h prolonged scan. MoSe2-ts@MoS2-ts can generate 147 μmol of H2 in ∼50 min of reaction time with 100% Faradaic efficiency.
Ag–Si artificial microflowers for plasmon-enhanced solar water splitting
(RSC, 2015) Basu, Mrinmoyee
We prepared Ag–Si microflowers as the photocathode for water splitting through a facile chemical method. The photocurrent and the hydrogen evolution rate of partially Ag particle decorated-Si microwires were enhanced through the synergistic effects of Ag co-catalytic and plasmonic assistance.
Ag2S/Ag Heterostructure: A Promising Electrocatalyst for the Hydrogen Evolution Reaction
(ACS, 2017) Basu, Mrinmoyee; Pande, Surojit; Gangopadhyay, Subhashis
Different metal chalcogenides, being a potential candidate for hydrogen evolution catalysts, have attracted enormous attention in the field of water splitting. In the present study, Ag2S/Ag is revealed as an efficient catalyst for hydrogen evolution. When a sacrificial template of the CuS nanostructure is used, Ag2S/Ag heterostructures are synthesized following a simple wet-chemical technique. Two different routes, wet chemical and hydrothermal, are followed to modulate the morphology of the CuS templates from flower ball to wirelike structures, which subsequently results in the formation of Ag2S nanostructure. Finally, the Ag layer is deposited on Ag2S with the help of a photoreduction technique. The unique heterostructure of Ag2S/Ag shows efficient catalytic activity in the H2 evolution reaction. A Ag2S/Ag wire can successfully generate a 10 mA/cm2 current density at a −0.199 V potential. Ag2S/Ag contains the micronanostructure where nanoplates of Ag2S/Ag assemble to give rise to microstructures such as flower balls and wire.
Aggregates of Ni/Ni(OH)2/NiOOH Nanoworms on Carbon Cloth for Electrocatalytic Hydrogen Evolution
(ACS, 2020-11-09) Basu, Mrinmoyee; Pande, Surojit
The development of an efficient electrocatalyst for hydrogen evolution reaction (HER) is essential to facilitate the practical application of water splitting. Here, we aim to develop an electrocatalyst, Ni/Ni(OH)2/NiOOH, via electrodeposition technique on carbon cloth, which shows efficient activity and durability for HER in an alkaline medium. Phase purity and morphology of the electrodeposited catalyst are determined using powder X-ray diffraction and electron microscopic techniques. The compositional and thermal stability of the catalyst is checked using X-ray photoelectron spectroscopy and thermogravimetry analysis. Electrodeposited Ni/Ni(OH)2/NiOOH material is an efficient, stable, and low-cost electrocatalyst for hydrogen evolution reaction in a 1.0 M KOH medium. The catalyst exhibits remarkable performance, achieving a current density of 10 mA/cm2 at a potential of −0.045 V vs reversible hydrogen electrode (RHE), and the Tafel slope value is 99.6 mV/dec. The overall electrocatalytic water splitting mechanism using Ni/Ni(OH)2/NiOOH catalyst is well explained, where formation and desorption of OH– ion on the catalyst surface are significant at alkaline pH. The developed electrocatalyst shows significant durability up to 200 h in a negative potential window in a highly corrosive alkaline environment along with efficient activity. The electrocatalyst can generate 165.6 μmol of H2 in ∼145 min of reaction time with 81.5% faradic efficiency.
AgPd Alloy Nanoparticles Decorated MoS2 2D Nanosheets: Efficient Hydrogen Evolution Catalyst in Wide pH Condition
(Wiley, 2019-01-08) Basu, Mrinmoyee
MoS2, MoS2/Ag, and AgPd alloy are developed as efficient HER catalyst in a wide range of pH condition. AgPd alloy nanoparticle is developed on the surface of MoS2, using MoS2/Ag as the precursor following galvanic exchange method. MoS2, MoS2/AgPd-1 and MoS2/AgPd-2 can generate unaltered current density up to 30 h.
An Aminolytic Approach toward Hierarchical β-Ni(OH)2 Nanoporous Architectures: A Bimodal Forum for Photocatalytic and Surface-Enhanced Raman Scattering Activity
(ACS, 2010) Basu, Mrinmoyee
A surfactantless, trouble-free, and gentle wet chemistry approach has been used to interpret the precisely controlled growth of β-Ni(OH)2 with the assistance of ammonia and nickel acetate from seedless mild hydrothermal conditions. A thorough investigation of the reaction kinetics and product morphology with varied concentration of NH3 and different reaction times suggests that a putative mechanism of dissolution, recrystallization, and oriented attachment supports the intelligent self-assembly of nanobuilding blocks. Associated characterizations (FTIR, PXRD, FESEM, EDAX, HRTEM, and Raman) have identified it to be pure β-Ni(OH)2 without any signature of contamination. The assembled units result in porous frameworks (nanoflowers and nanocolumns) and are indeed full of communally intersecting nanopetals/nanoplates with both lengths and widths on the order of micrometer to nanometer length scale. The as-synthesized material could also be used as a precursor for nanometric black NiO under calcination. The hydroxide has been found to be a potent and environmentally benign material because it warrants its photocatalytic activity through dye mineralization. Finally, Ni(OH)2 has been photochemically derivatized with dosages of silver nanoparticles bringing a competent composite authority Ag@Ni(OH)2, to give a full-proof enhanced field effect of prolific SERS activity. In a nutshell, these results are encouraging and fetch new promise for the fabrication of a low-cost and high-yielding greener synthetic protocol for a functional material with promising practicability.
AU nanoparticles on in2s3/in2o3 nanopyramids increase photoanodic activity in photoelectrochemical water splitting
(ACS, 2024-07) Basu, Mrinmoyee
To fulfill the increasing energy demand, photoelectrochemical (PEC) water splitting is an effective approach. For that, it is very important to give rise to efficient photoelectrodes for the PEC water splitting reaction as the anodic reaction is sluggish, and because of that the overall efficiency remains obstructed. In this context, In2S3/In2O3 nanopyramids with exposed (111) facets are developed following a simple hydrothermal method. Further, the effect of Au plasmonic nanoparticles (NPs) on the In2S3/In2O3 nanopyramid surface is investigated. Au NPs are decorated on In2S3/In2O3 nanopyramids by the thermal reduction method. The dipping time of In2S3/In2O3 in a Au-precursor solution is varied to alter the loading amount of Au. Au NPs enhance the light absorption of In2S3/In2O3 nanopyramids effectively from 600 to 800 nm. Furthermore, in the presence of Au NPs, carrier concentration is enhanced at the same time charge as transportation ability is also enhanced at the interface. The optimum decoration of Au NPs helps to achieve the efficient PEC activity. The best obtained In2S3/In2O3/Au in this study shows enhancement in photocurrent density by generating 5.16 mA/cm2 photocurrent density, which is nearly 3.66 times higher compared to that of In2S3/In2O3 at an applied potential of 0.599 V vs Ag/AgCl. Decoration of Au NPs also leads to a 2.6-fold higher carrier density and cathodic shift in onset potential. In2S3/In2O3/Au achieves a maximum photoconversion efficiency of nearly 1.18% at 0.26 V vs Ag/AgCl in 0.5 M Na2SO4 electrolyte. The In2S3/In2O3/Au nanostructure can even withstand the highly corrosive environment of 3.5% saline water. High photocurrent density of 4.52 mA/cm2 at 0.599 V vs Ag/AgCl can be generated by In2S3/In2O3/Au, where 3.5 wt % saline water is used as electrolyte. The developed photoelectrode: In2S3/In2O3–Au is capable of generating higher photocurrent at 0 V vs Ag/AgCl in 3.5% saline water compared to 0.5 M Na2SO4. Under continuous illumination for 3600 s in saline water, the stability of In2S3/In2O3/Au is observed.
Band gap tuning to improve the photoanodic activity of ZnInxSy for photoelectrochemical water oxidation
(RSC, 2019) Basu, Mrinmoyee
Photoelectrochemical (PEC) water splitting being a greener and ecofriendly pathway has become a renowned technique to generate hydrogen (H2). To attain remarkable photoconversion efficiency, it is highly required to develop efficient photoelectrodes for PEC water splitting. For this, ternary metal chalcogenide ZnInxSy (x = 1.6, 2, 2.2, and 3) is synthesized as an efficient photoanode for PEC water splitting. Tuning of morphology helps to improve the PEC performance through enhanced light absorption and charge transportation. Similarly, elemental doping is a very fruitful strategy to modulate the band structure. Here, a facile hydrothermal approach is developed to synthesize thin sheets of ZnInxSy (x = 1.6, 2, 2.2, and 3) followed by calcination. Through controlling the calcination time and the indium content, the band structure and morphology of ZnInxSy are modulated. The observed results indicate that ZnIn2.2Sy has the optimum and appropriate amount of indium content and oxygen doping. ZnIn2.2Sy can generate a maximum photocurrent density of 4.83 mA cm−2 at ‘0.7767’ vs. RHE. Furthermore, with the help of Mott–Schottky analysis the carrier density is calculated. The calculated carrier density of ZnIn2.2Sy is 7.886 × 1021 cm−3, which is 2.37, 1.77, and 3.69-fold higher compared to ZnInxSy (x = 1.6, 2, and 3). Photoconversion efficiency (η) is direct evidence to legitimize the superiority of ZnIn2.2Sy; it shows a maximum efficiency of 2.744% at potential 0.507 V vs. RHE. ZnIn2.2Sy shows high stability, i.e., it can generate nearly unaltered photocurrent density for 1000 seconds. The determined band alignment of ZnIn2.2Sy indicates the more negative shift of valence band energy compared to others, which promotes easy oxidation of H2O to O2.
CdIn2.2Sy Nanosheet-Based Photoanodes for Photoelectrochemical Water Splitting
(ACS, 2022-06) Basu, Mrinmoyee
Photoelectrochemical water splitting is a greener approach to produce hydrogen (H2) as an efficient chemical fuel for the future with high energy density. However, it is extremely challenging to develop suitable semiconductor materials with desired efficiency and stability, which can be applied for practical applications. Looking at the theoretical efficiency and the solar spectrum, it is clear that visible-light-active semiconductors are the most appealing candidates. Herein, CdIn2.2Sy (CIS), a visible light-active semiconductor, is explored as a photoanode for PEC water splitting. The thin nanosheets of CIS are grown vertically through a hydrothermal method. These can efficiently absorb visible light through multiple reflections and scattering of light inside the material and enhance the light–matter interaction. As a result, the developed CIS thin nanosheets produce a maximum photocurrent density of 3.97 mA/cm2 at “1.6” V versus RHE under continuous back illumination. On the other hand, CIS attains a maximum photoconversion efficiency of ∼1.72% at “0.60” V versus RHE. Furthermore, to improve the efficiency and stability, “S” and “N” codoped C-dots (S, N-CDs) are adorned on the CIS photoanode. The “S” and “N” codoped C-dots and CIS form the type-II heterostructure, which efficiently boosts the charge separation and transportation of photogenerated electrons and holes. The transient decay time becomes longer in the case of heterostructure compared to bare CIS. The heterostructure generates 11.2 mA/cm2 photocurrent densities at an applied potential of “1.6” V versus RHE. At the same time, the heterostructure CIS/S, N-CDs-B achieves a ∼2.08-fold higher photoconversion efficiency compared to bare CIS nanosheets and is stable up to 1500 s under continuous back illumination. The present work offers an approach for designing an efficient and stable photoanode for PEC water splitting.
Chelate Effect in Surface Enhanced Raman Scattering with Transition Metal Nanoparticles
(ACS, 2009-12-17) Basu, Mrinmoyee
Over the years, several protocols have been designed to achieve surface enhanced Raman scattering (SERS) from noble/coinage metal nanoparticles preferably with silver and gold owing to the local electromagnetic field enhancement near their surface. However, the higher value of the imaginary component of the dielectric constant and the coupling between conduction and interband electron transitions result in poor SERS intensity for transition metals. Therefore, a good number of approaches such as the development of various surface roughening procedures have been made to increase the SERS sensitivity involving transition metal nanoparticles. This letter reports that chelating ligands such as 1,10-phenanthroline, ethylenediammine, and so forth have been found to be superior alternatives to bring forth the SERS activity from “3d” block transition metal nanoparticles (nickel and cobalt). Thus, a comparative account of SERS efficiency derived from these materials as well as from coinage metal nanoparticles engaging chelating and nonchelating (e.g., pyridine) ligands becomes intriguing.
Construction of CuS/Au Heterostructure through a Simple Photoreduction Route for Enhanced Electrochemical Hydrogen Evolution and Photocatalysis
(Springer Nature, 2016-10-05) Pande, Surojit; Basu, Mrinmoyee; Nazir, Roshan
An efficient Hydrogen evolution catalyst has been developed by decorating Au nanoparticle on the surface of CuS nanostructure following a green and environmental friendly approach. CuS nanostructure is synthesized through a simple wet-chemical route. CuS being a visible light photocatalyst is introduced to function as an efficient reducing agent. Photogenerated electron is used to reduce Au(III) on the surface of CuS to prepare CuS/Au heterostructure. The as-obtained heterostructure shows excellent performance in electrochemical H2 evolution reaction with promising durability in acidic condition, which could work as an efficient alternative for novel metals. The most efficient CuS-Au heterostructure can generate 10 mA/cm2 current density upon application of 0.179 V vs. RHE. CuS-Au heterostructure can also perform as an efficient photocatalyst for the degradation of organic pollutant. This dual nature of CuS and CuS/Au both in electrocatalysis and photocatalysis has been unveiled in this study.
Construction of CuS/Au Heterostructure through a Simple Photoreduction Route for Enhanced Electrochemical Hydrogen Evolution and Photocatalysis
(Nature, 2016-10) Basu, Mrinmoyee; Pande, Surojit
An efficient Hydrogen evolution catalyst has been developed by decorating Au nanoparticle on the surface of CuS nanostructure following a green and environmental friendly approach. CuS nanostructure is synthesized through a simple wet-chemical route. CuS being a visible light photocatalyst is introduced to function as an efficient reducing agent. Photogenerated electron is used to reduce Au(III) on the surface of CuS to prepare CuS/Au heterostructure. The as-obtained heterostructure shows excellent performance in electrochemical H2 evolution reaction with promising durability in acidic condition, which could work as an efficient alternative for novel metals. The most efficient CuS-Au heterostructure can generate 10 mA/cm2 current density upon application of 0.179 V vs. RHE. CuS-Au heterostructure can also perform as an efficient photocatalyst for the degradation of organic pollutant. This dual nature of CuS and CuS/Au both in electrocatalysis and photocatalysis has been unveiled in this study
Controlling the aspect ratio and electrocatalytic properties of nickel cobaltite nanorods
(RSC, 2013) Basu, Mrinmoyee
NiCo2O4 nanorods (assembled with small nanoparticles) with different aspect ratios were synthesized through a surfactant mediated reverse micellar route. Anisotropy of the nickel cobaltite nanorods was retained after calcination of nickel cobalt oxalate precursors. A high aspect ratio (∼12) of the NiCo2O4 nanorods was obtained by using a cationic surfactant (CTAB) while a non-ionic surfactant (Tergitol) led to the formation of a much lower aspect ratio (∼5) of the nanorods. These nanorods could potentially be used as anodic electrocatalysts for the oxygen evolution reaction. Due to having a high surface roughness, nanorods assembled with the smallest particles, ∼5–10 nm in diameter (surface area ∼158 m2 g−1), show a high current density of ∼140 mA cm−2 with a low onset potential of ∼0.31 V (at 0.9 V) towards the oxygen evolution reaction and the values of current density is significantly higher than earlier reports.
A core@shell hollow heterostructure of Co3O4 and Co3S4: an efficient oxygen evolution catalyst
(RSC, 2019) Basu, Mrinmoyee
To avoid a massive energy crisis in the near future, it becomes urgent to develop efficient catalysts for the oxygen evolution reaction (OER) in water splitting. For this purpose, a two dimensional (2D) heterostructure of Co3O4 and Co3S4 is prepared following a simple multi-step method that incorporates a wet-chemical technique followed by a hydrothermal method. Initially, 2D sheets of Co3O4 are synthesized using the wet-chemical method followed by calcination. Finally, the heterostructure Co3O4@Co3S4 is fabricated from the Co3O4 sheets following a simple Kirkendall process through sulfurization for electrochemical application. Slow anion exchange leads to development of a hollow core@shell 2D Co3O4@Co3S4 heterostructure. After sulfidation, the heterostructure of 2D sheets shows excellent conductivity and improved electrocatalytic activity for the OER compared to bare Co3O4. The best-obtained Co3O4@Co3S4 can produce a 20 mA cm−2 current density upon application of 1.647 V vs. RHE, which is ∼100 mV lower compared to bare Co3O4. Sulfidation of Co3O4 leads to the formation of hollow heterostructures with a ∼2.8 times higher electrochemically active surface area. Co3O4@Co3S4 is very stable, and it can produce an unaltered current density up to 1000 continuous cycles in the OER.
CoSe2 Embedded in C3N4: An Efficient Photocathode for Photoelectrochemical Water Splitting
(ACS, 2016-09-16) Basu, Mrinmoyee
An efficient H2 evolution catalyst is developed by grafting CoSe2 nanorods into C3N4 nanosheets. The as-obtained C3N4–CoSe2 heterostructure can show excellent performance in H2 evolution with outstanding durability. To generate phatocathode for photoelectrochemical water splitting CoSe2 grafted in C3N4 was decorated on the top of p-Si microwires (MWs). p-Si/C3N4–CoSe2 heterostructure can work as an efficient photocathode material for solar H2 production in PEC water splitting. In 0.5 M H2SO4, p-Si/C3N4–CoSe2 can afford photocurrent density −4.89 mA/cm2 at “0” V vs RHE and it can efficiently work for 3.5 h under visible light. Superior activity of C3N4–CoSe2 compared to CoSe2 toward H2 evolution is explained with the help of impedance spectroscopy.
The CoTe2 nanostructure: an efficient and robust catalyst for hydrogen evolution
(RSC, 2015) Basu, Mrinmoyee
Cobalt ditelluride nanoparticles in a diameter range of 20–50 nm were synthesized as a new electrocatalyst for the hydrogen evolution reaction in 0.50 M H2SO4(aq). These nanoparticles can generate −10 mA cm−2 at an overpotential of 246 mV without any decay up to 48 h of continuous reaction.
CuO Barrier Limited Corrosion of Solid Cu2O Leading to Preferential Transport of Cu(I) Ion for Hollow Cu7S4 Cube Formation
(ACS, 2011) Basu, Mrinmoyee
Highly ordered, uniform Cu7S4 hollow cubes have been successfully synthesized in a mild, low-temperature condition from freshly prepared solid Cu2O cubes. Cu2O cubes have been synthesized at ∼80 °C, exploiting the water-soluble Cu(II)–EDTA complex (λmax = 730 nm) as precursor and glucose as reducing agent under alkaline conditions. In the synthetic pathway, Cu2O solid cubes act as corrosion-prone, sacrificial templates. Kinetic parameters describe the corrosion of Cu2O solid cubes in the presence of sulfide ions, which is the product of hydrolysis of thioacetamide. Corrosion results in a nonstoichiometric hollow Cu7S4 structure like a solid cubic template. Strong affinity of Cu(I) toward sulfide (“soft”–“soft” interaction) fetches Cu(I) from the central region of the solid Cu2O template, making hollow cubes of Cu7S4. Mechanistically, the thin film of the oxidized surface layer on Cu2O cubes protects the template. Then the oxidized layer offers resistance to the passage of sulfide ions for its inward transportation. Conversely, soft–soft affinity fetches Cu(I) ions from inside. Finally, hollow Cu7S4 cubes are formed at the solid–liquid interface. The transformation process has been further examined and confirmed from UV–visible spectroscopy, scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectra, and impedance measurement. Hollow Cu7S4 cubes with increased surface area are generated from solid Cu2O cubes via Kirkendall diffusion.
Decoration of Carbon Nitride Surface with Bimetallic Nanoparticles (Ag/Pt, Ag/Pd, and Ag/Au) via Galvanic Exchange for Hydrogen Evolution Reaction
(ACS, 2017) Basu, Mrinmoyee; Pande, Surojit
Here, we propose the synthesis of AgPt, AgPd, and AgAu bimetallic nanoparticles (NPs) on a carbon nitride (C3N4) surface via a galvanic exchange technique for the hydrogen evolution reaction (HER). Prior to the synthesis of C3N4/AgPt, AgPd, and AgAu, Ag NPs were synthesized on a C3N4 surface. For the synthesis of Ag NPs, initially Ag+ ions were adsorbed and then reduced by NaBH4 resulting in the decoration of Ag NPs. These Ag NPs were then subjected to galvanic exchange where sacrificial Ag was replaced by Pt2+, Pd2+, and Au3+ to fabricate AgPt, AgPd, and AgAu NPs. The galvanic exchange reaction occurs on a solid substrate, which favored slow exchange of Ag and resulted in the transformation of Ag into AgPt, AgPd, and AgAu alloys. The synthesized heterostructures were characterized with the help of PXRD, XPS, TEM, FESEM, and EDS techniques. All the materials were applied for hydrogen evolution using 0.5 M H2SO4 solution. C3N4/AgPt shows efficient electrocatalytic activity as it requires only −150 mV potential to attain current density of 10 mA/cm2. Bimetallic catalysts synthesized through galvanic exchange proved very efficient as compared to monometallic C3N4/Ag.
Decoration of Carbon Nitride Surface with Bimetallic Nanoparticles (Ag/Pt, Ag/Pd, and Ag/Au) via Galvanic Exchange for Hydrogen Evolution Reaction
(ACS, 2017-08-21) Basu, Mrinmoyee; Pande, Surojit
Here, we propose the synthesis of AgPt, AgPd, and AgAu bimetallic nanoparticles (NPs) on a carbon nitride (C3N4) surface via a galvanic exchange technique for the hydrogen evolution reaction (HER). Prior to the synthesis of C3N4/AgPt, AgPd, and AgAu, Ag NPs were synthesized on a C3N4 surface. For the synthesis of Ag NPs, initially Ag+ ions were adsorbed and then reduced by NaBH4 resulting in the decoration of Ag NPs. These Ag NPs were then subjected to galvanic exchange where sacrificial Ag was replaced by Pt2+, Pd2+, and Au3+ to fabricate AgPt, AgPd, and AgAu NPs. The galvanic exchange reaction occurs on a solid substrate, which favored slow exchange of Ag and resulted in the transformation of Ag into AgPt, AgPd, and AgAu alloys. The synthesized heterostructures were characterized with the help of PXRD, XPS, TEM, FESEM, and EDS techniques. All the materials were applied for hydrogen evolution using 0.5 M H2SO4 solution. C3N4/AgPt shows efficient electrocatalytic activity as it requires only −150 mV potential to attain current density of 10 mA/cm2. Bimetallic catalysts synthesized through galvanic exchange proved very efficient as compared to monometallic C3N4/Ag.