From Ensemble Electrochemistry to Nano‐Impact Electrochemistry: Altered Reaction Selectivity

Abstract

Selective electrochemical production of valued chemicals is of significant importance but remains a great challenge in chemistry. Conventional approaches for enhancing reaction selectivity focus on the improvement of the catalysts themselves. In this work, we systematically studied the reaction kinetics and mass transport behavior of LaNiO3 nanocubes (LaNiO3 NCs) catalyzed hydrogen peroxide reduction reaction (HPRR) at ensemble and single nanoparticle levels using nano‐impact electrochemistry (NIE). We find that the selectivity of HPRR was altered at individual random‐walk nanoparticles as compared to their ensemble counterpart without changing the reaction kinetics, due to the significantly enhanced mass transport at single nanoparticles. This discovery offers the scope of new catalytic approaches for engineering electrochemical reactions in general.

Multiphase Chemistry under Nanoconfinement: An Electrochemical Perspective

“…Figure a displays the electrolysis collisions that refers to the electro-oxidation or electroreduction of the redox-active entities, which causes the transient increase in i – t responses. − The dimensions, compositions, and concentrations of target entities can be determined by statistically analyzing the high-throughput current signals. The second type describes the collisions of electrocatalytically active NPs with the catalytically inert UME. − These collisions enable one to observe the enhanced current responses, where an electrochemical reaction occurs on the impacting particle once it is in electrical connection with the working electrode. The inelastic adsorption of individual NPs on the UME surface results in a steady-state increase of current.…”

Simple and Efficient Method for Screening Electrocatalyst Supports at the Single Nanoparticle Level

“…Single NP collision electrochemistry (SNCE) can measure the transient signals from individual events when single NPs stochastically collide with an ultramicroelectrode. − Therefore, the SNCE method provides a unique tool for determining the intrinsic activity and reaction kinetics of individual electrocatalysts . Moreover, high mass transfer of single NPs on the ultramicroelectrode can avoid ensemble and film effects that are often encountered during the conventional electrocatalytic measurements on a macroscopic scale. , Recently, SNCE has already demonstrated its screening capabilities in the case of bimetallic NPs toward methanol oxidation and ORR .…”

Carbon Nanotubes as Controllable Electric-Field-Induced Bipolar Electrodes for Efficient Water Purification

“…Although few pioneer works have been conducted, − the performance is not quite satisfactory, and the mechanism still needs to be carefully investigated. For example, reactive oxygen species (ROSs) were the main oxidants in the bipolar electrode process, but their production ability was limited. , The effect of the electric field on the electrochemical behaviors of conducting materials remains a long-term dispute: monopolar electrode versus bipolar electrode. ,− Therefore, we aimed to address the above-mentioned scientific and practical issues in this work.…”