Surface-functionalized three-dimensional MXene supports to boost the hydrogen evolution activity of Pt catalysts in alkaline media

Abstract

Distinctive surface functional groups on 3D MXenes as Pt-supports are correlated with optimized Pt–H affinity and HER activity in alkaline media.

Versatile MXene Gels Assisted by Brief and Low-Strength Centrifugation

“…Figures 2 d, S15 , S16 and Table S1 further show that such transitions in surface chemistry of Ti 3 C 2 T x MXenes were reversible, since both the FTIR and XPS absorptions of pristine pH 4 gel can be recovered after an alternate alkaline and acid treatments. Similar findings can be discovered in Hong et al’s work [ 46 ], where the –F terminations of Ti 3 C 2 T x MXene can gradually evolve to –OH and then to –O after an alkali-induced treatment, and the resultant Ti 3 C 2 (OH) x and Ti 3 C 2 O x powders regained a relatively high amount of –F groups after re-submerged in HF solutions. Hence, the pH-controlled internal structural alterations of MXene gel can be attributed to an interplay between the protonation/deprotonation of –OH groups and reversible conversion between the terminal –F and –O, which determined the strength between the competitive hydrogen bonding associations and mutual electrostatic repulsions among the nanosheets.…”

Platinum Species on Oxygen Vacancy-Rich Titania for Efficient Basic Electrocatalytic Hydrogen Evolution

“…This is because there are more hydronium ions in acidic environments, which are easier to adsorb on the surface of catalysts and combine with catalysts to form hydrogen intermediates, while in alkaline environments, the number of protons is limited, so the process of breaking the hydrogen–oxygen bond of water molecules is relatively slow, which becomes the rate-limiting step as in refs − . According to the principle of Sabatier Qs, platinum (Pt) is considered to be the most iconic catalyst for the hydrogen evolution reaction (HER) because its hydrogen adsorption free energy (Δ G H* = 0.05 eV) is closest to 0 eV, even the most active Pt catalysts are two to three orders of magnitude less active in neutral/basic media than in acidic media. − However, the high cost of Pt and the corrosion of equipment in acidic conditions seriously hinder its practical application, and it is very important to develop Pt-based catalysts with low loading and high catalytic activity in alkaline media. , …”

A Review of the Recent Advances in Development of Noble Metal‐Free Materials as Electrocatalysts for Hydrogen and Oxygen Evolution Reactions

“…[24] In the field of electrocatalysis, there is an enormous necessity to expand electrocatalysts with high catalytic activity, long-term stability, and good electrical conductivity. Up to now, although the noble metal nanomaterials like Pd, Pt, Ir, Ru, and Rh elements have been extensively identified as the most effective electrocatalysts toward the OER and HER (e. g. Pt-based electrocatalysts for HER, Ir-based and Ru-based electrocatalysts for OER), [25][26][27] they have some disadvantages, including high cost and poor stability in long-term oxidative environments. [28] In the last years, most studies have focused on the expansion and design of high-performance and earth-abundant water-splitting electrocatalysts due to their high electrocatalytic efficiency and low cost.…”