Dendritic Ferroselite (FeSe₂) with 2D Carbon-Based Nanosheets of rGO and g-C₃N₄ as Efficient Catalysts for Electrochemical Hydrogen Evolution

Abstract

Nanostructured transition metal dichalcogenides are demonstrated to be potential catalysts to produce molecular hydrogen through electroreduction of water. Finding an efficient and cost-effective catalyst as a substitute for a platinum-based catalyst for sustainable hydrogen production is still a major issue, more so for large-scale production. Herein, we have designed dendritic ferroselite (FeSe 2 ) hybrid nanocomposites with 2D g-C 3 N 4 and reduced graphene oxide (rGO) nanosheets, that is, FeSe 2 /g-C 3 N 4 and FeSe 2 / rGO as electrocatalysts for hydrogen evolution reaction (HER). Interestingly, FeSe 2 /rGO exhibited higher performance compared to FeSe 2 /g-C 3 N 4 . The highly conductive 2D FeSe 2 /rGO hybrid with an aligned curvy rippling surface and dendritic morphology demonstrates an onset potential of 218 mV at a current density of 10 mV/ cm 2 versus reversible hydrogen electrode in comparison to that of FeSe 2 /g-C 3 N 4 showing an onset potential of 437 mV. The detailed density functional theory (DFT) calculations were performed to investigate the intrinsic catalytic sites and Gibbs free energy (ΔG H* ) of hydrogen adsorption for the HER process. The DFT calculations displayed 0.33 V less overpotential for carbon atoms of g-C 3 N 4 (0.97 V) compared to rGO (1.3 V). In contrast, hybrids of FeSe 2 /rGO (0.86 V) display lower overpotential when compared to FeSe 2 /g-C 3 N 4 (1.63 V), which is in agreement with experimental results. Electrochemical impedance spectroscopy reveals lower charge transfer resistance (R ct ) for FeSe 2 /rGO. The high hydrogen evolution activity of FeSe 2 /rGO is due to the electrocatalytic synergistic effect of iron diselenide and rGO, contributing to the optimum free energy for HER and improved electron mobility.

Boosting Photocatalytic Activity Using Carbon Nitride Based 2D/2D van der Waals Heterojunctions

“…[551][552][553]553 The 0D/1D hybrid FeSe 2 and ZnSe demonstrated increased photosplitting of water due to better charge separation in the type-I heterojunction. 554 Other heterojunctions such as 1D/2D FeSe 2 /MoSe 2 and FeSe 2 nanodendrites decorated on GO and g-C 3 N 4 have been reported 555,556 Remarkable results were obtained by the marriage of 2D FeSe 2 and 2D sheets of g-C 3 N 4 (CN NS ) (Figure 21). 557 The synthesis of 2D/2D FeSe 2 /CN NS was achieved via the formation of g-C 3 N 4 sheets followed by in situ growth of FeSe 2 using Fe(acac) 3 and Se precursors in the presence of 1octadecene (ODE) and oleylamine (OLA) (Figure 21a).…”

“…FeSe 2 exhibits an excellent conductivity (resistivity ≈10 –3 Ω·cm), populated surface iron atoms, low toxicity, and benign nature and is favorable for the water splitting due to the presence of abundant [Fe–Fe] hydrogenase type active centers accelerating proton adsorption and H 2 O 2 decomposition. , Even with such excellent properties, photocatalytic applications of FeSe 2 are sparse, and most of the applications of FeSe 2 are limited to solar cells and the sodium-ion battery (SIB). − , The 0D/1D hybrid FeSe 2 and ZnSe demonstrated increased photosplitting of water due to better charge separation in the type-I heterojunction . Other heterojunctions such as 1D/2D FeSe 2 /MoSe 2 and FeSe 2 nanodendrites decorated on GO and g-C 3 N 4 have been reported , …”

Novel Carbene Anchored Molecular Catalysts for Hydrogen Evolution Reactions

“…Of late, nanocrystals, nanoparticles, and hydrogel films of transition metal chalcogenides, transition metal carbides, layered double hydroxides, and transition metal phosphides are largely explored for HER as efficient substitutes for platinum . Interestingly, there have been a lot of reports on metal chalcogenide-based materials that have been largely explored for HER − However, several inadequacies are associated with their preparation such as high operational temperature, high vacuum, and the state-of-the-art instrumentation facility required for their appropriate characterization, which collectively make them costly and energy intensive.…”

Review on Electrochemical Sensing of Triclosan using Nanostructured Semiconductor Materials

“…Several advanced techniques had been utilized for the detection of TCS at low concentrations namely electrochemical sensing, chemiluminescence (CL), liquid chromatography‐mass spectroscopy (LC–MS), liquid chromatography–ultraviolet detector(LC‐UVD), gas chromatography ion trap mass spectrometry (GCITMS) and gas chromatography–atomic emission detection (GC‐AED) among which the electrochemical sensing is well suitable for detection of TCS because of its easy fabrication, cost‐effective, portable, quick response, low detection limit with high degree of sensitivity, which have attracted considerable attention over the drawbacks of other techniques which are complicated to operate and time consuming [7] . The electrochemical workstation consists of working electrode, counter electrode (CE) and reference electrode (RE) [8] . The most popular working electrode is the glassy carbon electrode (GCE), paper‐based electrode system which includes screen printed carbon electrode (SPCE) [9] .…”

“…[7] The electrochemical workstation consists of working electrode, counter electrode (CE) and reference electrode (RE). [8] The most popular working electrode is the glassy carbon electrode (GCE), paper-based electrode system which includes screen printed carbon electrode (SPCE). [9] Originally, electrochemical behavior of TCS can be determined by applying cyclic voltammetry technique by using simple electrochemical sensors.…”