Amorphous Doping Promotes Utilization of Fe‐Doped Amorphous Zr(HPO₄)₂ for Superb Water Oxidation Electrocatalysis

Abstract

Mn, [18] which can play an indispensable role in tuning the electrocatalytic activity. It is well known that the electrochemical reaction mainly occurs on the surface of the catalyst. [19] Therefore, realizing effective surface doping can improve the utilization of dopant atoms to obtain superb electrocatalytic performance. Nevertheless, most of the doping occurs inside the host, so achieving effective surface doping is an enormous challenge. [20] In recent years, amorphous materials have been widely used in electrocatalysis due to their short-range order and long-range disorder nature. More importantly, the composition of amorphous nanomaterials is more flexible and can be adjusted in a wider range to obtain suitable catalytic active centers. [21,22] Meanwhile, the surface of the amorphous nanomaterials possesses a large scale of coordinated unsaturated sites with high surface energy, strong activation ability as well as highly active center density. [23,24] Thus, the above unique structure merits may accommodate doping ions with different sizes and valence, inducing more exposure of dopant to form steady state and achieving high dopant atom utilization. The above discussion motivates us to look into amorphous doping, and further fabricate a suitable amorphous catalyst model to investigate exposed dopant as an active site for enhanced electrocatalytic performance.In terms of electrocatalysis, the most promising application is electrocatalytic water splitting which can solve environmental pollution, especially the depletion of fossil energy. [25,26] And the key to realize the large-scale application of electrocatalysis water splitting in the market is to reduce the overpotential of oxygen evolution reaction (OER). For that OER is hindered by the slow four-electron transfer process and has become a bottleneck, hampering the development of green electrolyzed water technology. [27,28] Traditionally, Ru/Ir oxides belong to the most stateof-the-art electrocatalysts for OER in electrolytes with different pH. [29,30] The shortage of these noble metal catalysts and high expense stint their large-scale practical utilization. [31] Given these, transition metal phosphates have gained popular attention on account of their noteworthy catalytic activity, especially the abundant resource, opening new avenues for hopeful development of other phosphate electrocatalysts. [32][33][34] Despite this, phosphate zirconium phosphates (α-ZrP), as a typical phosphate, is rarely used in the field of electrolyzed water because of the inherent relative inert activity and poor conductivity. [35] For example, metal-modified ZrP nanoparticles electrocatalyst Doping hetero-atoms on the surface of host materials, namely effective doping with high atom utilization, is a promising strategy to optimize the activity of electrocatalysts for water electrolysis, especially for oxygen evolution reaction (OER). Herein, high utilization of doped atoms is successfully achieved in Fe-doped 2D amorphous Zr(HPO 4 ) 2 nanosheets (amorphous Fe-ZrP). Due to the u...

Design of earth‐abundant amorphous transition metal‐based catalysts for electrooxidation of small molecules: Advances and perspectives

“…Compared with anionic doping, cationic doping is more prevalent, and the most frequently used dopants are Fe and Ni. 44,64,209,210 Generally, cationic doping can improve the electrical conductivity and modify catalysts' electronic structures, thereby upgrading the catalytic performance.…”

“…The N‐dopant can tailor the electronic structure of CoFe selenites and thus leads to a high OER performance ( η 10 = 242 mV, Tafel slope = 59.1 mV dec −1 ). Compared with anionic doping, cationic doping is more prevalent, and the most frequently used dopants are Fe and Ni 44,64,209,210 . Generally, cationic doping can improve the electrical conductivity and modify catalysts’ electronic structures, thereby upgrading the catalytic performance.…”

Advances and insights in amorphous electrocatalyst towards water splitting

“…This problem can be solved to some extent by elemental doping, and it is widely believed that bimetallic centers lower the thermodynamic potential barrier and promote the formation of O-O bonds. Among the transition metal-based OER catalysts, Fe-based oxides, hydroxides, hydroxyl oxides, and sulfides have been studied extensively [172][173][174][175][176] because of their high electrocatalytic activity and low preparation cost [177,178].…”