Hydrolysis mechanism of YbB2C2 and the microstructure of the carbon derived from the hydrolysis reaction.

• Graphite crystal is formed during a room-temperature hydrolysis process of novel layered compound YbB 2 C 2. In addition, YbB 6 , Yb 3 (OH) 3 n (BO 3) (3- n) sol, hydrogen, hydrocarbons, and carbon oxides form simultaneously. • H, B, O, and Yb in Yb 3 (OH) 3 n (BO 3) (3- n) sol are identified by electronic energy loss spectrometer (EELS). • The hydrolysis mechanism of YbB 2 C 2 is reasonably demonstrated by a molecular cell model: Yb³⁺ ion acts as cathode where H 2 O molecule is reduced to H atom and OH⁻ ion, while (B 2 C 2)³⁻ acts as anode where OH⁻ ion is oxidized to O atom. Carbide-derived carbon (CDC) materials have gained great attention due to the excellent properties for various potential applications. Here, graphite crystal is formed during a room-temperature hydrolysis process of layered compound YbB 2 C 2. The formation mechanism can be demonstrated by a YbB 2 C 2 molecular cell: Yb³⁺ acts as a cathode where H 2 O molecule is reduced to H atom and OH⁻ ion, while (B 2 C 2)³⁻ acts as an anode where OH⁻ ion is oxidized to O atom. Then, YbB 2 C 2 molecular cell begins to disintegrate, i.e., Yb³⁺ ion, B and C atoms dissociate from the molecular cell. The as-produced C atoms combine to form graphite crystal. The initial graphite crystal is a cabbage-like microsphere, and then it gradually disintegrates and transforms into layered graphite. In addition, YbB 6 , Yb 3 (OH) 3 n (BO 3) (3- n) sol, hydrogen, hydrocarbons, and carbon oxides form simultaneously. Our method provides a general and inexpensive route to obtain carbide-derived graphite crystal. [ABSTRACT FROM AUTHOR]