Metal doped carbon nanoneedles and effect of carbon organization with activity for hydrogen evolution reaction (HER)

• Cellulose nanowhiskers are used to produce carbon nanomaterials.
• A size selection process is used to improve the quality of cellulose nanowhikers.
• The effect of metals in the graphitization process of cellulose is evaluated.
• Carbon nanoneedles are used as catalyst for hydrogen evolution reaction.

Cellulose nanowhiskers (CNW) from cotton, was prepared by acid hydrolysis and purified using a size selection process to obtain homogeneous samples with average particle size of 270 nm and 85.5% crystallinity. Purified CNW was used as precursor to carbon nanoneedles (CNN) synthesis. The synthesis of CNN loaded with different metals dopants were carried out by a nanoreactor method and the obtained CNNs applied as electrocatalysts for hydrogen evolution reaction (HER). In the carbon nanoneedles synthesis, Ni, Cu, or Fe worked as graphitization catalyst and the metal were found present as dopants in the final material. The used metal appeared to have direct influence on the degree of organization of the particles and also in the surface density of polar groups. It was evaluated the influence of the graphitic organization on the general properties and nickel was found as the more appropriate metal since it leads to a more organized material and also to a high activity toward HER.