Abstract

Two-dimensional transition metal dichalcogenides (TMDs) are a new family of 2D materials with features that make them appealing for potential applications in nanomaterials science and engineering. Recently, these 2D TMDs have attracted a great research interest because of the abundant choice of materials with diverse and tunable electronic, optical, chemical, and electrocatalytic properties. Although, the edges of the 2D TMDs show excellent electrocatalytic performance, their basal plane (001) is inert which hinders the industrial applications for electrocatalysis. Transition metal/chalcogen atom vacancies or doping with some other foreign atoms may be a remedy to activate the inert basal plane. Here, we have computationally designed the 2D monolayer MoSe₂ and studied its electronic properties with electrocatalytic activities. Pt-atom has been doped in the pristine 2D MoSe₂ (i.e., Pt-MoSe₂) to activate the inert basal plane resulting zero bandgap. This study reveals that the Pt-MoSe₂ is an excellent bifunctional electrocatalyst for both the hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR) with the aid of the first principle-based hybrid density functional theory (DFT). Periodic hybrid DFT method has been applied to compute the electronic properties of both the pristine MoSe₂ and Pt-MoSe2. To determine both the HER and ORR mechanisms on the surface of the Pt-MoSe₂ material, a non-periodic DFT calculation has been performed by considering a molecular Pt₁-Mo₉Se₂₁ cluster model. The present study shows that the 2D Pt-MoSe₂ follows Volmer-Heyrovsky mechanism for HER with the energy barriers about 9.29 kcal.mol-1 and 10.55 kcal.mol-1 during the H˙-migration and Heyrovsky reactions. The ORR is achieved by four-electron transfer mechanism with the formation of two transition energy barriers about 14.94 kcal.mol-1 and 11.10 kcal.mol-1, respectively. The lower energy barriers and high turnover frequency during the reactions expose that the Pt-MoSe₂ can be adopted as an efficient bifunctional electrocatalyst for both the HER and ORR. The present studies demonstrate that the exceptional HER and ORR activity and stability performance shown by the MoSe₂ electrocatalyst can be enhanced by Pt-doping, opening a promising concept for the sensible design of high-performance catalyst for H₂ production and O₂ reduction.

Abstract

Two-dimensional transition metal dichalcogenides (TMDs) are a new family of 2D materials with features that make them appealing for potential applications in nanomaterials science and engineering. Recently, these 2D TMDs have attracted a great research interest because of the abundant choice of materials with diverse and tunable electronic, optical, chemical, and electrocatalytic properties. Although, the edges of the 2D TMDs show excellent electrocatalytic performance, their basal plane (001) is inert which hinders the industrial applications for electrocatalysis. Transition metal/chalcogen atom vacancies or doping with some other foreign atoms may be a remedy to activate the inert basal plane. Here, we have computationally designed the 2D monolayer MoSe₂ and studied its electronic properties with electrocatalytic activities. Pt-atom has been doped in the pristine 2D MoSe₂ (i.e., Pt-MoSe₂) to activate the inert basal plane resulting zero bandgap. This study reveals that the Pt-MoSe₂ is an excellent bifunctional electrocatalyst for both the hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR) with the aid of the first principle-based hybrid density functional theory (DFT). Periodic hybrid DFT method has been applied to compute the electronic properties of both the pristine MoSe₂ and Pt-MoSe2. To determine both the HER and ORR mechanisms on the surface of the Pt-MoSe₂ material, a non-periodic DFT calculation has been performed by considering a molecular Pt₁-Mo₉Se₂₁ cluster model. The present study shows that the 2D Pt-MoSe₂ follows Volmer-Heyrovsky mechanism for HER with the energy barriers about 9.29 kcal.mol-1 and 10.55 kcal.mol-1 during the H˙-migration and Heyrovsky reactions. The ORR is achieved by four-electron transfer mechanism with the formation of two transition energy barriers about 14.94 kcal.mol-1 and 11.10 kcal.mol-1, respectively. The lower energy barriers and high turnover frequency during the reactions expose that the Pt-MoSe₂ can be adopted as an efficient bifunctional electrocatalyst for both the HER and ORR. The present studies demonstrate that the exceptional HER and ORR activity and stability performance shown by the MoSe₂ electrocatalyst can be enhanced by Pt-doping, opening a promising concept for the sensible design of high-performance catalyst for H₂ production and O₂ reduction.

Abstract

Two-dimensional transition metal dichalcogenides (TMDs) are a new family of 2D materials with features that make them appealing for potential applications in nanomaterials science and engineering. Recently, these 2D TMDs have attracted a great research interest because of the abundant choice of materials with diverse and tunable electronic, optical, chemical, and electrocatalytic properties. Although, the edges of the 2D TMDs show excellent electrocatalytic performance, their basal plane (001) is inert which hinders the industrial applications for electrocatalysis. Transition metal/chalcogen atom vacancies or doping with some other foreign atoms may be a remedy to activate the inert basal plane. Here, we have computationally designed the 2D monolayer MoSe₂ and studied its electronic properties with electrocatalytic activities. Pt-atom has been doped in the pristine 2D MoSe₂ (i.e., Pt-MoSe₂) to activate the inert basal plane resulting zero bandgap. This study reveals that the Pt-MoSe₂ is an excellent bifunctional electrocatalyst for both the hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR) with the aid of the first principle-based hybrid density functional theory (DFT). Periodic hybrid DFT method has been applied to compute the electronic properties of both the pristine MoSe₂ and Pt-MoSe2. To determine both the HER and ORR mechanisms on the surface of the Pt-MoSe₂ material, a non-periodic DFT calculation has been performed by considering a molecular Pt₁-Mo₉Se₂₁ cluster model. The present study shows that the 2D Pt-MoSe₂ follows Volmer-Heyrovsky mechanism for HER with the energy barriers about 9.29 kcal.mol-1 and 10.55 kcal.mol-1 during the H˙-migration and Heyrovsky reactions. The ORR is achieved by four-electron transfer mechanism with the formation of two transition energy barriers about 14.94 kcal.mol-1 and 11.10 kcal.mol-1, respectively. The lower energy barriers and high turnover frequency during the reactions expose that the Pt-MoSe₂ can be adopted as an efficient bifunctional electrocatalyst for both the HER and ORR. The present studies demonstrate that the exceptional HER and ORR activity and stability performance shown by the MoSe₂ electrocatalyst can be enhanced by Pt-doping, opening a promising concept for the sensible design of high-performance catalyst for H₂ production and O₂ reduction.

Abstract

Two-dimensional transition metal dichalcogenides (TMDs) are a new family of 2D materials with features that make them appealing for potential applications in nanomaterials science and engineering. Recently, these 2D TMDs have attracted a great research interest because of the abundant choice of materials with diverse and tunable electronic, optical, chemical, and electrocatalytic properties. Although, the edges of the 2D TMDs show excellent electrocatalytic performance, their basal plane (001) is inert which hinders the industrial applications for electrocatalysis. Transition metal/chalcogen atom vacancies or doping with some other foreign atoms may be a remedy to activate the inert basal plane. Here, we have computationally designed the 2D monolayer MoSe₂ and studied its electronic properties with electrocatalytic activities. Pt-atom has been doped in the pristine 2D MoSe₂ (i.e., Pt-MoSe₂) to activate the inert basal plane resulting zero bandgap. This study reveals that the Pt-MoSe₂ is an excellent bifunctional electrocatalyst for both the hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR) with the aid of the first principle-based hybrid density functional theory (DFT). Periodic hybrid DFT method has been applied to compute the electronic properties of both the pristine MoSe₂ and Pt-MoSe2. To determine both the HER and ORR mechanisms on the surface of the Pt-MoSe₂ material, a non-periodic DFT calculation has been performed by considering a molecular Pt₁-Mo₉Se₂₁ cluster model. The present study shows that the 2D Pt-MoSe₂ follows Volmer-Heyrovsky mechanism for HER with the energy barriers about 9.29 kcal.mol-1 and 10.55 kcal.mol-1 during the H˙-migration and Heyrovsky reactions. The ORR is achieved by four-electron transfer mechanism with the formation of two transition energy barriers about 14.94 kcal.mol-1 and 11.10 kcal.mol-1, respectively. The lower energy barriers and high turnover frequency during the reactions expose that the Pt-MoSe₂ can be adopted as an efficient bifunctional electrocatalyst for both the HER and ORR. The present studies demonstrate that the exceptional HER and ORR activity and stability performance shown by the MoSe₂ electrocatalyst can be enhanced by Pt-doping, opening a promising concept for the sensible design of high-performance catalyst for H₂ production and O₂ reduction.