The use of proton exchange membrane (PEM) hydrolysis technology offers promise for environmentally friendly hydrogen production using renewable energy. However, the development of efficient, economical, and durable bifunctional electrocatalysts for acid oxygen evolution (OER) and hydrogen evolution (HER) remains a challenge. To solve this problem, we synthesized the RuO2 CeO2 heterojunction (RuO2 ceo2@c) loaded on a carbon sphere by hydrothermal and annealing techniques. Our experiments demonstrate the specific catalytic activity of RUO2 ceo2@c on OER and HER at 0In 5 M H2SO4, the overpotentials are 170 mV and 120 mV at 10 mA cm2, respectively. In addition, the electrocatalyst is capable of 1Full hydrolysis was achieved at 54 V and stability was maintained at 10 mA cm2 for more than 100 h. Density functional theory (DFT) calculations show that the RuO2 CeO2 heterojunction changes the center of the D-band of Ru, balances the adsorption and desorption behavior of H, accelerates the reaction kinetics, reduces the energy barrier, and thus improves the electrocatalytic activity. These findings provide valuable insights into the design of efficient bifunctional hydrolysis electrocatalysts in the future.
Schematic diagram of the RUO2 ceo2@c synthesis.
A) SEM diagram of RUO2 ceo2@c, (B) TEM diagram of RUO2 ceo2@c with size distribution, (C) HRTEM diagram of RUO2 ceo2@c, (D) XRD diagram of RUO2 ceo2@c, ceo2@cand ruo2@c, (E) element diagram of RUO2 ceo2@c.
A) RU 3P XPS spectra for RUO2 ceo2@c and ruo2@c, (B) CE 3D XPS spectra for RUO2 ceo2@c and ceo2@c, (C) O 1S XPS spectra for RUO2 ceo2@c, (D) O 1S XPS spectra for RUO2 ceo2@c.
A) polarization curves, (B) corresponding Tafel plots, (c) Nyquist plots of RUO2 ceo2@c, ruo2@c, ceo2@c and commercial RUO2. (d) RuO2 ceo2@c chronopotentiometric assay at 10 mA cm2 and 50 mA cm2.
A) Polarization curves, (B) corresponding Tafel plots, (C) Nyquist plots of RuO2 ceo2@c, ruo2@c, ceo2@c and commercial PT C (20 wt%), (D) Time potentiometric assays of RuO2 ceo2@c at 10 mA cm2 and 50 mA cm2.
a) Configured full cell polarization curve, (b) ruo2 ceo2@c||Long-term stability testing of the RUO2 ceo2@c.
a) the geometry of RuO2 CEO2, (b) the four-step process of OER, (c) the OER free energy diagram of RuO2 CEO2 and RuO2, (d) the HER free energy diagram of PT, RuO2 CEO2 and RuO2, (e) the projected density of states (DOS) of RuO2 CEO2, and f) the projected density of states (DOS) of RuO2. With pt ( 009 ev).
In this study, we synthesized the RuO2 CeO2 heterostructure and loaded it on a carbon sphere through a precise hydrothermal and annealing process. The results showed that the ceo2@c heterostructure of the RuO2 showed excellent electrocatalytic activity and stability for both OER and HER in a wide pH range. In particular, ruo2 ceo2@c heterostructure at 0The overpotentials of OER and HER are 170 220 mV and 120 82 mV, respectively, and the current density is 10 mA cm2 under the condition of 5 M H2SO4 and 1 M KOH, respectively. DFT calculations show that the RuO2 CeO2 heterojunction reduces the center of the D-band of Ru, thereby balancing the adsorption and desorption behavior of H and improving the reaction kinetics. In addition, the two-electrode water electrolysis experiment showed that ruO2 ceo2@c||ruo2 ceo2@c in 1A current density of 10 mA cm2 can be achieved at 54 V, highlighting the importance of loading the RUO2 CEO2 heterojunction on the carbon sphere to achieve the dual functions of HER, OER, and total hydrolysis. The heterostructure of RuO2 CeO2 on conductive carbon designed in this study provides a valuable reference for the preparation of high-efficiency hydrogen-producing electrocatalysts.
ruo2/ceo2 heterostructure anchored on carbon spheres as a bifunctional electrocatalyst for efficient water splitting in acidic media - sciencedirect