Electrodeposition of Nanocrystalline Aluminium from 1-Ethyl-3-methylimidazolium Chloroaluminate with Niacinamide as an Efficient Additive

Nanocrystalline aluminium has been used as a promising energetic material due to its unique properties. However, the traditional methods for nanocrystalline aluminium production suffer from many inherent problems, which restrict the large-scale industrial application. In this paper, a systematic study was carried out on the nucleation mechanism and electrodeposition behaviour of nanocrystalline aluminium in Lewis acidic 1-ethyl-3-methylimidazolium chloroaluminate ionic liquid. It was found that niacinamide could be used as an effective additive in the preparation of nanocrystalline aluminium. According to electrochemical measurements and computational calculations, niacinamide was highly electroactive and polarized, which is probably attributed to nonuniform distributions of positive and negative charges on niacinamide. Its strong interaction with the electrode and subsequent adsorption onto the surface of aluminium nuclei prevented the further growth of crystals. Consequently, nanocrystalline aluminium was obtained at 313.2-333.2 K and 3-6 mA/cm(2) from 1-ethyl-3-methylimidazolium chloroaluminate that contained 8-12 mmol/kg niacinamide. Smooth and compact aluminium crystals with a minimum grain size of 20-30 nm could be electrodeposited at 313.2 K and 6 mA/cm(2) with 8-12 mmol/kg niacinamide. The molar concentration of additive, temperature and current density were confirmed as the major influencing factors in the electrodeposition of nanocrystalline aluminium from the chloroaluminate ionic liquid. It is expected that this work may be useful for the future preparation and application of nanocrystalline aluminium

Deployment of Coal Briquettes and Improved Stoves: Possibly an Option for both Environment and Climate

The use of coal briquettes and improved stoves by Chinese households has been encouraged by the government as a means of reducing air pollution and health impacts. In this study we have shown that these two improvements also relate to climate change. Our experimental measurements indicate that if all coal were burned as briquettes in improved stoves, particulate matter (PM), organic carbon (OC), and black carbon (BC) could be annually reduced by 63 +/- 12%, 61 +/- 10%, and 98 +/- 1.7%, respectively. Also, the ratio of BC to OC (BC/OC) could be reduced by about 97%, from 0.49 to 0.016, which would make the primary emissions of household coal combustion more optically scattering. Therefore, it is suggested that the government consider the possibility of: (i) phasing out direct burning of bituminous raw-coal-chunks in households; (ii) phasing out simple stoves in households; and, (iii) financially supporting the research, production, and popularization of improved stoves and efficient coal briquettes. These actions may have considerable environmental benefits by reducing emissions and mitigating some of the impacts of household coal burning on the climate. International cooperation is required both technologically and financially to accelerate the emission reduction in the world

Electrodeposition of Nanocrystalline Aluminium from 1-Ethyl-3-methylimidazolium Chloroaluminate with Niacinamide as an Efficient Additive

Nanocrystalline aluminium has been used as a promising energetic material due to its unique properties. However, the traditional methods for nanocrystalline aluminium production suffer from many inherent problems, which restrict the large-scale industrial application. In this paper, a systematic study was carried out on the nucleation mechanism and electrodeposition behaviour of nanocrystalline aluminium in Lewis acidic 1-ethyl-3-methylimidazolium chloroaluminate ionic liquid. It was found that niacinamide could be used as an effective additive in the preparation of nanocrystalline aluminium. According to electrochemical measurements and computational calculations, niacinamide was highly electroactive and polarized, which is probably attributed to nonuniform distributions of positive and negative charges on niacinamide. Its strong interaction with the electrode and subsequent adsorption onto the surface of aluminium nuclei prevented the further growth of crystals. Consequently, nanocrystalline aluminium was obtained at 313.2-333.2 K and 3-6 mA/cm(2) from 1-ethyl-3-methylimidazolium chloroaluminate that contained 8-12 mmol/kg niacinamide. Smooth and compact aluminium crystals with a minimum grain size of 20-30 nm could be electrodeposited at 313.2 K and 6 mA/cm(2) with 8-12 mmol/kg niacinamide. The molar concentration of additive, temperature and current density were confirmed as the major influencing factors in the electrodeposition of nanocrystalline aluminium from the chloroaluminate ionic liquid. It is expected that this work may be useful for the future preparation and application of nanocrystalline aluminium