Self-assembly photocatalytic reduction synthesis of graphene-encapusulated LaNiO3 nanoreactor with high efficiency and stability for photocatalytic water splitting to hydrogen

Reduced graphene oxide encapsulated LaNiO3 (LNO-RGO) composites were synthesized as crumpled nanoreactors via a facile self-assembly photocatalytic reduction method. The structures and properties of synthesized materials were systematically investigated. The characterization results revealed that LNO nanoparticles were encapsulated in RGO sheets with meso-macroporous framework, which was beneficial to the adsorption and diffusion of methanol and further promote to the capture of photogenerated holes. The anchoring effect of oxygen vacancies and chemical bonding reactions between LNO and RGO contributed to the encapsulated structure. The forming NieC bond produced to the strong interaction between LNO and RGO, which acted as a bridge to promote the effective separation of photogenerated electrons and holes. The as-prepared LNO-RGO nanoreactors presented high performance of photocatalytic activity and stability for H-2 evolution from water in the presence of methanol as a scavenger. A maximum H2 production rate of 3.22 mmol h(-1) g(-1) was obtained over a LNO-5% RGO photocatalyst which was 12 times higher than that of pure LNO with excellent long-term stability for 36 h.