Synergistic Fe−Se Atom Pairs as Bifunctional Oxygen Electrocatalysts Boost Low‐Temperature Rechargeable Zn‐Air Battery

Abstract

Herein, we successfully construct bifunctional electrocatalysts by synthesizing atomically dispersed Fe−Se atom pairs supported on N‐doped carbon (Fe−Se/NC). The obtained Fe−Se/NC shows a noteworthy bifunctional oxygen catalytic performance with a low potential difference of 0.698 V, far superior to that of reported Fe‐based single‐atom catalysts. The theoretical calculations reveal that p‐d orbital hybridization around the Fe−Se atom pairs leads to remarkably asymmetrical polarized charge distributions. Fe−Se/NC based solid‐state rechargeable Zn‐air batteries (ZABs−Fe−Se/NC) present stable charge/discharge of 200 h (1090 cycles) at 20 mA cm−2 at 25 °C, which is 6.9 times of ZABs−Pt/C+Ir/C. At extremely low temperature of −40 °C, ZABs−Fe−Se/NC displays an ultra‐robust cycling performance of 741 h (4041 cycles) at 1 mA cm−2, which is about 11.7 times of ZABs−Pt/C+Ir/C. More importantly, ZABs−Fe−Se/NC could be operated for 133 h (725 cycles) even at 5 mA cm−2 at −40 °C.

A Fe Single Atom Seed‐Mediated Strategy Toward Fe3C/FeNC Catalysts with Outstanding Bifunctional ORR/OER Activities

“…[7,48,49] Regulation of the local coordination environment of metal centers in SACs can significantly enhance the OER performance. [18,21,[50][51][52][53] As expected, the introduction of foreign Fe 3 C species leads to a remarkable improvement of the OER activity (Figure 3c), evidenced by the relatively low potential (E j10 ) of 1.809 V versus RHE required to achieve a current density of 10 mA cm −2 on Fe-N-C/Fe 3 Cl. For Fe-N-C/Fe 3 C-op, E j10 value is only 1.579 V versus RHE, comparable to that of Pt/C + RuO 2 (1.63 V).…”

Cobalt selenide with ordered cation vacancies for efficient oxygen reduction and frigostable Al–air batteries

“…37 The intensity ratio of the D-band to the G-band (I D /I G ) was 1.89 for Co 0.85 Se@N,Se-CNFs, higher than the others', disclosing a larger amount of disordered C atoms in the graphitized network of Co 0.85 Se@N,Se-CNFs. 38,39 Higher degree of defects in carbon could propel the ORR kinetics more energetically. The graphitic carbon could enhance the conductivity of the Co-Se species to accelerate electron transferring.…”

Recent advances of single-atom catalysts in CO2 conversion

“…[41][42][43] The most crucial issues call for innovations in catalytic systems through cost-efficient, high-activity, controlled selectivity, and long-term stability catalysts. [44][45][46] As a result, improving and adjusting catalytic materials have become the core in the study for CO 2 utilization technologies, with significant progress having been obtained at present. 47 Yet, considerable challenges still remain.…”