Solar‐Driven Interfacial Evaporation Accelerated Electrocatalytic Water Splitting on 2D Perovskite Oxide/MXene Heterostructure

Abstract

The rational design of economic and high‐performance electrocatalytic water‐splitting systems is of great significance for energy and environmental sustainability. Developing a sustainable energy conversion‐assisted electrocatalytic process provides a promising novel approach to effectively boost its performance. Herein, a self‐sustained water‐splitting system originated from the heterostructure of perovskite oxide with 2D Ti3C2Tx MXene on Ni foam (La1‐xSrxCoO3/Ti3C2Tx MXene/Ni) that shows high activity for solar‐powered water evaporation and simultaneous electrocatalytic water splitting is presented. The all‐in‐one interfacial electrocatalyst exhibits highly improved oxygen evolution reaction (OER) performance with a low overpotential of 279 mV at 10 mA cm−2 and a small Tafel slope of 74.3 mV dec−1, superior to previously reported perovskite oxide‐based electrocatalysts. Density functional theory calculations reveal that the integration of La0.9Sr0.1CoO3 with Ti3C2Tx MXene can lower the energy barrier for the electron transfer and decrease the OER overpotential, while COMSOL simulations unveil that interfacial solar evaporation could induce OH− enrichment near the catalyst surfaces and enhance the convection flow above the catalysts to remove the generated gas, remarkably accelerating the kinetics of electrocatalytic water splitting.

Janus Nano‐Micro Structure‐Enabled Coupling of Photothermal Conversion, Heat Localization and Water Supply for High‐Efficiency Solar‐Driven Interfacial Evaporation

“…The low heat convection loss in small regions facilitates the evaporation of water molecules, which agrees with experimental results in some previous reports. [31,32] PVA and Janus nano-micro structures are believed to result in the reduction of evaporation enthalpy. We then calculated the evaporation enthalpy change and corresponding solar-to-vapor conversion efficiency under 1 sun illumination (see Supporting Information for the calculation details).…”

Boosting Water Evaporation by Construction of Photothermal Materials with a Biomimetic Black Soil Aggregate Structure

“…Fresh water and energy scarcity have become two of the most challenging issues of the 21st century as populations grow and fossil resources deplete. − Considering the environmental and economic aspects, solar-driven evaporation, − as an environmentally friendly technology, is now a reliable way to get fresh water. − Benefiting from a lot of exploration work by researchers in the past, the interface isolation evaporator has been widely applied, including water transport, thermal management, and the design of photothermal materials to achieve high photothermal conversion capacity, − which can maximize the evaporation rate compared with the traditional floating evaporation device, which is in direct contact with water. − However, considering the salt pollution of the photothermal evaporation layer in the long-term desalination, the photothermal conversion technology is still difficult to achieve long-term stable operation in practical application.…”

Synergistic photothermal conversion and photocatalysis in 2D/2D MXene/Bi2S3 hybrids for efficient solar-driven water purification

“…13 Yang and co-authors successfully fabricated MXene/perovskite oxide composites and demonstrated improved simultaneous water purification performance. 14 Despite the great progress in this field, the development of economic, easy to prepare, and stable photothermal membranes based on MXenes is persistently needed.…”