PtCo@PtSn Heterojunction with High Stability/Activity for pH‐Universal H₂ Evolution

Abstract

Developing highly efficient Pt‐based catalysts through interface engineering is significant for hydrogen production by water electrolysis working at pH‐universal conditions but still challenging. Herein, a PtCo@PtSn heterojunction with good hydrogen evolution reaction (HER) performance in pH‐universal electrolytes is designed and prepared by combining the advantages of a Pt‐based bimetallic alloy and heterojunction. Density functional theory simulations illustrate that the surface electronic structure of Pt is optimized by interface engineering to effectively improve the ability of water dissociation and decrease the PtH bond strength for obtaining the suitable H* Gibbs free energy (∆GH*). It shows low HER overpotentials in 1.0 m KOH (η−10 = 25 mV), 1.0 m phosphate‐buffered saline (η−10 = 18 mV), and 0.5 m H2SO4 (η−10 = 21 mV) solutions, respectively, and it can steadily work for 100 000 (100k) cycles by cyclic voltammetry method. Thus, this work provides a novel strategy to design Pt‐based hydrogen evolution catalyst with robust catalytic performance.

Tuning d‐Band Center of Pt by PtCo‐PtSn Heterostructure for Enhanced Oxygen Reduction Reaction Performance

“…[47] Qiao et al [48] coupled Pt with CoO to form hybrid catalysts, suggesting that the significant enhancement of activity and stability is attributed to the interface interactions between Pt and CoO. Additionally, Pt also coupled with other metal oxides to form engineering hybrid materials such as CeO 2 , [49] TiO 2 , [50,51] etc., which are characterized by the improved intrinsic activity and stability toward oxygen evolution reaction (OER), [52] hydrogen evolution reaction (HER), [53,54] and ORR. [55] Based on the above, we introduce Sn and Co elements into Pt and use post-treated at high temperatures to form PtCo-PtSn/C heterostructure for efficiently boosting the activity and long-term stability.…”

Rational Design of Better Hydrogen Evolution Electrocatalysts for Water Splitting: A Review

“…Interface effect refers to the interface between two types of active materials due to strong bonding, electronic interaction or synergistic effect, which can form more active centers than individual components. [ 250 , 251 , 252 , 253 , 254 , 255 , 256 , 257 , 258 , 259 , 260 , 261 , 262 , 263 , 264 , 265 , 266 , 267 , 268 , 269 ] The complex electronic structures of interfacial electrocatalysts make the fundamental investigations of structure‐activity relationships still remain as a great challenge. Nevertheless, this complexity also introduces various structural features that can be adjusted advantageously.…”

Recent progress on the long‐term stability of hydrogen evolution reaction electrocatalysts

“…Yin et al have constructed Pt-based bimetallic alloys and heterojunction (PtCo@PtSn) by a three-step heat-treatment-hydrothermal-heat treatment process to enhance the stability for pH-universal H 2 evolution. 27 DFT theoretical calculations show that PtCo@PtSn heterojunction presents the lowest ΔG H* and water dissociation energy (0.03/0.49 eV) compared to PtCo (À0.174/0.61 eV) and PtSn (0.398/0.65 eV), indicating the faster hydrogen adsorption and desorption, as well as timely hydrogen replenishment (Figure 5I). The introduction of Sn and Co elements modulates the 73 Copyright 2019, The Royal Society of Chemistry.…”

“…Reproduced with permission. 27 Copyright 2021, Wiley-VCH commercialization. The reports so far still have Pt as the main active site, and aim to reduce the amount of Pt and improve stability by some strategies, such as stabilizing the Pt element by alloying with other elements, spacelimited metal atoms, clusters, or strong metal-support interactions.…”

“…Here, we highlight the recent advances in the robust heterogeneous electrocatalysts for HER in various electrolytes. Generally, heterogeneous HER catalysts are classified into three categories (Figure 1): noble metal‐based (NMB), transition metal‐based (TMB), and metal‐free catalysts (MFC) 27–50 . This review addresses the current progress of catalytic stability of the heterogeneous HER electrocatalysts.…”