Ag-Doped WO₃ Nanoplates as Heterogenous Multifunctional Catalyst for Glycerol Acetylation, Electrocatalytic and Enhanced Photocatalytic Hydrogen Production

Abstract

Herein, we report a hydrothermal method to synthesize pristine and Agdoped WO 3 nanoplates and study their multifunctional competence in the accomplishment of enhanced catalytic organic conversion and highly efficient photocatalytic and electrocatalytic H 2 evolution reactions. The as-synthesized nanoplates were characterized by using various techniques including X-ray diffraction, field emission scanning electron microscopy-energy-dispersive X-ray analysis, transmission electron microscopy, UV−vis diffuse reflectance spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy, and BET surface area studies. The significant catalytic performance was shown by 1% Agdoped WO 3 nanoplates with 100% glycerol conversion and 90% triacetin selectivity. The photocatalytic activity was also examined toward water splitting H 2 evolution reaction which demonstrates the highest H 2 evolution of 12.06 mmol g −1 catalyst for 1% Ag-doped WO 3 nanoplates in a time span of 8 h. Moreover, the electrocatalytic hydrogen evolution reaction was also monitored in acidic media (0.1 M H 2 SO 4 ) which demonstrates good results for 1% Ag-doped WO 3 nanoplates with a low overpotential of 0.53 V and a low Tafel slope of 40 mV dec −1 .

MoS2 Nanoflower-Deposited g-C3N4 Nanosheet 2D/2D Heterojunction for Efficient Photo/Electrocatalytic Hydrogen Evolution

“…14,15 PC and PEC water splitting thrives upon the advanced activity and elongated stability of visible-light-driven catalytic systems as it comprises nearly 45% of solar energy reaching out to earth. 16,17 In this context, the tunability of the band gap emerges as a critical optical parameter that governs the dynamics of charge carrier separation and migration (e−h+ pair), essential for facilitating efficient visible-light-driven PC and PEC water-splitting processes. 18,19 The strategic utilization of p−n heterojunction formation for hydrogen evolution represents a visionary approach in order to enhance the effectiveness of the water-splitting reaction.…”

“…The generation of H 2 fuel through ecofriendly and sustainable methods represents a crucial solution to global energy shortages and the pressing problem of global warming. − Over the past few decades, green hydrogen (H 2 ) production through water splitting has gained the interest of researchers due to high gravimetric density of H 2 , which promises to be used effectively as a sustainable energy resource to meet the current energy demand. , For the achievement of scalable water-splitting reactions, a prudent choice of a catalytic system is required to carry out efficient H 2 evolution. , The scalable applicability of green H 2 production is a nontrivial undertaking that requires optimized reactors and catalytic systems that can perform synergistically . Motivated by this approach, photocatalytic (PC), electrocatalytic (EC), and photoelectrocatalytic (PEC) water-splitting strategies are promising pathways for sustainable energy solutions. ,, The hydrogen evolution reaction (HER) through PC, EC, and PEC water splitting is a low-energy process primarily driven by photon and electrical energy sources. − Since the exceptional work of Honda and Fujishima on TiO 2 -assisted PEC water splitting, a diverse range of catalytic systems have been developed such as noble metal, metal oxides, metal chalcogenides, multiferroics, , graphene-based catalysts, etc., and exploited in PC, EC, and PEC water-splitting operations. , PC and PEC water splitting thrives upon the advanced activity and elongated stability of visible-light-driven catalytic systems as it comprises nearly 45% of solar energy reaching out to earth. , In this context, the tunability of the band gap emerges as a critical optical parameter that governs the dynamics of charge carrier separation and migration (e–h+ pair), essential for facilitating efficient visible-light-driven PC and PEC water-splitting processes. , …”

Unveiling the Bifunctional Photo/Electrocatalytic Activity of In Situ Grown CdSe QDs on g-C3N4 Nanosheet Z-Scheme Heterostructures for Efficient Hydrogen Generation

“…Due to energy shortage and environmental concerns, there is a great deal of interest in alternate energy storage and conversion systems. , Hydrogen is considered a potential replacement for conventional traditional fuels because of its high energy density and environmental-friendly combustion products. − The photo/electrocatalytic water splitting is a promising method for the conversion of solar and electrical energy into chemical fuels. , Significant efforts have been undertaken over the past few decades to produce highly efficient catalysts for the H 2 evolution reaction (HER). The noble metal-based HER catalysts, such as platinum, ruthenium, etc., have proven to be the most efficient catalyst, to date .…”

Symbiotic MoO3–SrTiO3 Heterostructured Nanocatalysts for Sustainable Hydrogen Energy: Combined Experimental and Theoretical Simulations

“…39 Also, these materials tend to be relatively cheaper than the conventionally used noble metals in HER such as Pt, Pd, Au, or Ag. 40,41 Numerous chemical methodologies are available in the literature for the fabrication of metal oxide nanostructures such as precursor-based microemulsion route, 42 reverse micellar method, 43 or solvothermal method; 44 however, we have fabricated MoO 3 −SrTiO 3 nanostructures via an environmentally friendly sol−gel precursor route. 45 In this work, we have modified SrTiO 3 nanoparticles by incorporating MoO 3 with an aim to improve its catalytic efficiency principally to enhance the rate of photochemical, EC, and PEC water splitting for H 2 evolution.…”

“…Interestingly, the ionic radius of Mo 6+ ions (0.062 nm) is quite comparable to that of Ti 4+ ions (0.0605 nm); this resemblance of ionic radii makes the equiatomic substitution of Ti sites by Mo 6+ ions feasible. , Noble metal-free MoO 3 –SrTiO 3 Z-scheme-heterostructured nanocatalysts have been fabricated owing to their improved chemical stability, cost effectiveness, and environment friendliness. − MoO 3 -based heterostructures have been exploited in the EC and PEC water splitting operations as well owing to their enhanced optoelectronic properties, which stimulate their usage . Also, these materials tend to be relatively cheaper than the conventionally used noble metals in HER such as Pt, Pd, Au, or Ag. , …”