Surface bonding of CoP to biomass derived carbon microtube: Site-specific growth and high-efficiency catalysis

The imitation and exploration of natural structures and characteristics are the inspiration source for science and technology progress. Herein, we report a method for preparing CoP anchored carbon microtubes (CoP@BCMT) by continuous hydrothermal, carbonization and phosphorization processes using cattail fibers (CFs) as carbon sources. The surface hydroxyl (–OH) groups acted as the growth sites for CoP fixed and grew in special positions. Co was anchored to BCMT surface through –OH groups and C-O-Co bonds were formed between CoP and BCMT. Surface bonding can ensure the growth of CoP at specific sites. The ultra-thin carbon layer covered CoP was deposited by the deposition of suspended carbon during CFs carbonization. CoP size, dispersibility and adhesion were maintained well due to surface coating and bonding. C-O-Co bonds promoted electron transfer and optimized adsorption energy of hydrogen, which was evaluated by density functional theory calculations. CoP@BCMT exhibited a low overpotential of 49 mV at current density of 10 mA cm −2 and long-term stability for 72 h. We modified commercial carbon nanotubes with surface hydroxyl groups and then combined with CoP, which greatly improved the catalytic performance. This work provides us with ideas for learning and using biomass to prepare advanced catalysts.