Synthesis of Water-Dispersible Single-Layer CoAl-Carbonate Layered Double Hydroxide.

Despite extensive study on single-layer layered double hydroxides (SL-LDHs) with NO3- counterions, SL-LDHs with CO32- counterions (CO32- SL-LDHs) have never been prepared before. Herein, a CoAl-CO32- SL-LDH which stays stable in water and powdery state is first synthesized using ethylene glycol as a reaction medium. The SL-LDH, with thickness of ∼0.85 nm, is composed of one Co(Al)O6 layer sandwiched between two CO32- layers. The SL-LDH powder shows high specific surface area (∼289 m2/g) and excellent electrocatalytic oxygen evolution efficiency. This work provides the first simple way to prepare CO32- SL-LDHs and will open an avenue for synthesizing other SL-LDHs.