Highly Porous Carbon from Microalga, Chlorella Vulgaris, as an Electrochemical Hydrogen Storage Material

Abstract

Chlorella Vulgaris, as a well-known green microalga is considered as a reliable biomass source with vast biotechnological potential to produce various high-performance products. In the present study, porous carbon with a specific surface area was produced via a hydrothermal technique. The investigated materials were characterized by Fourier-transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), energy-dispersive X-ray (EDX), Brunauer-Emmett-Teller (BET) and transmission electron microscopy (TEM). The electrochemical hydrogen storage (EHS) capacity of the product was investigated by a three-electrode system (chronopotentiometry) in 6 M KOH electrolyte. The microalga-based porous carbons showed a good electrochemical hydrogen storage capacity equal to 1040 mAh g −1 (≈3.9 wt%) after 40 cycles. This great capacity principally is due to the porous structure (distributions of pore size is mesoporous), high surface area (718 m 2 g −1 ), and proper surface functional groups (C−OH, C-O-S and COO − ) of prepared microalga-based porous carbons. These results suggested that the microalgal biomass could be successfully applied in electrochemical storage of hydrogen.

The impacts of nitrogen doping on the electrochemical hydrogen storage in a carbon

“…Among multitudinous hydrogen storage methods, the electrochemical hydrogen storage of carbonbased materials can be carried out directly at or close to ambient conditions, for example, at room temperature and low pressure. [20][21][22][23][24][25][26] Besides, the electrochemical hydrogen storage also possesses the merits of simplicity, reusability and safety. 27 The mechanism of electrochemical storage contains a few steps as described below: [13][14][15]24,[28][29][30][31] I.…”

“…To develop a safe and efficient hydrogen storage system with high energy density remains an enormous challenge. Among multitudinous hydrogen storage methods, the electrochemical hydrogen storage of carbon‐based materials can be carried out directly at or close to ambient conditions, for example, at room temperature and low pressure 20‐26 . Besides, the electrochemical hydrogen storage also possesses the merits of simplicity, reusability and safety 27 .…”