Ethylene Glycol Electro-Oxidation on Platinum-Free Surfaces: How the Composition of PdRuRh Surfaces Influences the Catalysis

et al. 2023

Preprint

The cost-effective production of green hydrogen is one of the most important challenges for a sustainable energy transition. To decrease the cost in the production of hydrogen through electrolysis, there are several obstacles that must be overcome. For instance, more active and stable anodes made of abundant and cheap materials will contribute to lowering the capital and operational expenditure of the process. It is well-known that the oxidation of water requires high overpotentials, which is the main limitation for the performance of the device. In this context, substituting the oxidation of water (OER) at the anode of electrolyzers by the oxidation of biomass-derived substances contribute to the overall process by decreasing the power input of the devices and, in some cases, by producing value-added chemicals. Herein, we re-visited some of the most important fundamental aspects of the (electro-)oxidation of alcohols and polyols on metal-based catalysts, focusing on reaction descriptors. Then, we moved to the (electro-)oxidation of these molecules on metal oxides, re-visiting some of the literature about their application in heterogeneous catalysis and for OER, to get insights about the relation of the structure of the materials and their activity. Due to the lack of fundamental knowledge about the electro-oxidation of alcohols and polyols on metallic oxides and to the vast literature about the use of perovskite oxides for OER, we propose to start systematic studies using perovskite oxides for the electrooxidation of alcohols and polyols. Consequently, we presented results for LaCoO3, LaFeO3, LaMnO3, and LaNiO3, and propose a mechanism for the electro-oxidation of glycerol based on the formation and reactivity of MOH(O) species. We believe that fundamental and systematic studies in this topic would permit the establishment of reaction descriptors, speeding up the searching for suitable materials for this reaction and paving the way for a most cost-effective production of green hydrogen.

Section: (Electro-)oxidation Of Bigger Molecules On Metalsmentioning

confidence: 99%

Perovskite oxides as an opportunity to systematically study the Electrooxidation of alcohols and Polyols on materials based on abundant elements: Learning from the experience using pure metals and metallic oxides in (Electro-)catalysis

et al. 2023

Preprint

“…Studies about the electrooxidation of ethylene glycol, , ethanol, − glycerol, , and glucose , have mainly focused on the determination of reaction products and intermediates by combining several electrochemical and analytical tools. Some works have used electrochemical, analytical, and computational tools to arrive at a more general understanding, from the atomic point of view, of the first steps that occur in the electrooxidation of polyols. , In these works, researchers have focused on compounds with low oxygenation degrees, which generate several value-added chemicals.…”

Section: Electrooxidation Of Alcohols and Polyols On Metalsmentioning

confidence: 99%

“…115−117 Although the reaction mechanism is more complicated in alkaline media due to the instability of several aldehydes and ketones, which are generated electrochemically but are then quickly oxidized in solution, 118,119 the higher activity and stability of several materials (important for the concomitant H 2 production) encouraged researchers to work in high pHs. 103,113 Apart from Pt, metals such as Pd, 104,105 Au, 96 Ni, 26,29,120 and Ag 113,121 have been used for the electrooxidation of small organic molecules due to the lower cost and/or higher abundance. Unfortunately, the reactions occur at much higher potentials, matching the formation of oxygenated species at the electrocatalyst surface, suggesting again the key role of these species.…”

Section: Electrooxidation Of Bigger Molecules On Metalsmentioning

confidence: 99%

Perovskite Oxides as an Opportunity to Systematically Study the Electrooxidation of Alcohols and Polyols on Materials Based on Abundant Elements: Learning from the Experience Using Pure Metals and Metallic Oxides in Electrocatalysis

ACS Appl. Energy Mater.

et al. 2023

The cost-effective production of green hydrogen is one of the most important challenges for a sustainable energy transition. To decrease the cost of the production of hydrogen through electrolysis, there are several obstacles that must be overcome. For instance, more active and stable anodes made of abundant and cheap materials will contribute to lowering capital and operational expenditure. It is well known that the oxidation of water requires high overpotentials, which is the main limitation of the performance of the device. In this context, substituting the oxidation of water [oxygen evolution reaction (OER)] at the anode of electrolyzers by the oxidation of biomass-derived substances contributes to the overall process by decreasing the power input of the devices and, in some cases, by producing value-added chemicals. Herein, we revisited some of the most important fundamental aspects of the electrooxidation of alcohols and polyols on metal-based catalysts, focusing on reaction descriptors. Then, we moved to the electrooxidation of these molecules on metal oxides, revisiting some of the literature about their application in heterogeneous catalysis and for OER, to get insights about the relation of the structure of the materials and their activity. Due to the lack of fundamental knowledge about the electrooxidation of alcohols and polyols on metallic oxides and to the vast literature about the use of perovskite oxides for OER, we propose to start systematic studies using perovskite oxides for the electrooxidation of alcohols and polyols. Consequently, we presented results for LaCoO3, LaFeO3, LaMnO3, and LaNiO3 and proposed a mechanism for the electrooxidation of glycerol based on the formation and reactivity of MOH(O) species. We believe that fundamental and systematic studies on this topic would permit the establishment of reaction descriptors, speeding up the search for suitable materials for this reaction and paving the way for more cost-effective production of green hydrogen.

Section: (Electro)oxidation Of Bigger Molecules On Metalsmentioning

confidence: 99%

“…Apart from Pt, metals such as Pd 102,103 , Au 93 , Ni 26,29,120 and Ag 107,112,121 have been used for the electrooxidation of small organic molecules due to the lower cost and/or higher abundance. Unfortunately, the reactions occur at much higher potentials matching the formation of oxygenated species at the electrocatalyst surface, suggesting again the key role of these species.…”

Section: (Electro)oxidation Of Bigger Molecules On Metalsmentioning

confidence: 99%

Perovskite oxides as an opportunity to systematically study the Electrooxidation of alcohols and Polyols on materials based on abundant elements: Learning from the experience using pure metals and metallic oxides in (Electro-)catalysis

et al. 2022

Preprint

The cost-effective production of green hydrogen is one of the most important challenges for a sustainable energy transition. To decrease the cost in the production of hydrogen through electrolysis, there are several obstacles that must be overcome. For instance, more active and stable anodes made of abundant and cheap materials will contribute to lowering the capital and operational expenditure of the process. It is well-known that the oxidation of water requires high overpotentials, which is the main limitation for the performance of the device. In this context, we believe that substituting the oxidation of water (OER) at the anode of electrolyzers by the oxidation of biomass-derived substances could contribute to the overall process by decreasing the power input of the devices and, in some cases, by producing value-added chemicals. Herein, we re-visited some of the most important fundamental aspects of the (electro-)oxidation of alcohols and polyols on metal-based catalysts, focusing on reaction descriptors. Then, we moved to the (electro-)oxidation of these molecules on metal oxides, re-visiting some of the literature about their application in heterogeneous catalysis and for OER, to get insights about the relation of the structure of the materials and their activity. Due to the lack of fundamental knowledge about the electro-oxidation of alcohols and polyols on metallic oxides and to the vast literature about the use of perovskite oxides for OER, we propose to start systematic studies using perovskite oxides for the electrooxidation of alcohols and polyols. We believe that fundamental studies in this topic would permit the establishment of reaction descriptors, speeding up the searching for suitable materials for this reaction and paving the way for a most cost-effective production of green hydrogen.