Highly Effective Freshwater and Seawater Electrolysis Enabled by Atomic Rh‐Modulated Co‐CoO Lateral Heterostructures

Abstract

Atomic metal‐modulated heterostructures have been evidenced as an exciting solution to develop high‐performance multifunctional electrocatalyst toward water splitting. In this research, a catalyst of continuous cobalt‐cobalt oxide (Co‐CoO) lateral heterostructures implanted with well‐dispersed rhodium (Rh) atoms and shelled over conductive porous 1D copper (Cu) nano‐supports for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in both freshwater and seawater under alkaline condition is proposed. It is found that synergistic effects coming from uniform Rh atoms at doping level and Co‐CoO heterostructures afford rich multi‐integrated active sites and excellent charge transfer, thereby effectively promoting both HER and OER activities. The material requires overpotentials of 107.3 and 137.7 mV for HER and 277.7 and 260 mV for OER to reach an output of 10 mA cm−1 in freshwater and mimic seawater, respectively, surpassing earlier reported catalysts. Compared to a benchmark a Pt/C//RuO2‐based two‐electrode electrolyzer, a device derived from the 1D‐Cu@Co‐CoO/Rh on copper foam delivers comparable cell voltages of 1.62, 1.60, and 1.70 V at 10 mA cm−2 in freshwater, mimic seawater, and natural seawater, respectively, together with robust stability. These results evidence that 1D‐Cu@Co‐CoO/Rh is a promising catalyst for green hydrogen generation via freshwater and seawater electrolysis applications.

Boosting efficient alkaline fresh water and seawater electrolysis via electrochemical reconstruction

“…As shown in Fig. 5(e), compared to other state-of-the-art alkaline seawater electrolyzers, 33,53–62 Fe 0.01 -Ni&Ni 0.2 Mo 0.8 N‖Fe 0.01 &Mo-NiO delivers a record-high current density of 688 mA cm −2 at the voltage of 1.7 V. Compared to our previous study of a two-electrode electrolyzer using NiMoN as the cathode and NiFeN/NiMoN as the anode, the current density of Fe 0.01 -Ni&Ni 0.2 Mo 0.8 N‖Fe 0.01 &Mo-NiO at 1.7 V is about 2.2 times as large. 33 These results reveal the excellent seawater electrolysis performance of Fe 0.01 -Ni&Ni 0.2 Mo 0.8 N‖Fe 0.01 &Mo-NiO and again underscore the importance of utilizing electrochemical reconstruction for the design of highly active bifunctional catalysts.…”

Energy‐Saving Hydrogen Production by Seawater Electrolysis Coupling Sulfion Degradation

“…[13] Huge electricity consumption (>4.5-6 kWh per m 3 H 2 ) also remains a major bottleneck impeding the commercial application of seawater electrolysis. [13][14][15] So far, the development of energy-saving and chlorine-free seawater electrolysis technologies for sustainable and cost-effective hydrogen production is still extremely challenging.…”

Competitive Coordination‐Pairing between Ru Clusters and Single‐Atoms for Efficient Hydrogen Evolution Reaction in Alkaline Seawater

“…[35] By comparing the over potential at 10 mA cm −2 (η 10 ) in alkaline and seawater media with those reported in previous literature (Figure 4h; Tables S4 and S5, Supporting Information), it can be seen that Ru 1,n -ZnFe 2 O x -C delivers the best performance in Ru−based materials, as the most active alkaline HER catalysts to our knowledge. [5,31,[36][37][38]…”