Sunil Kumar Ramasahayam

Microwave assisted synthesis and characterization of silicon and phosphorous co-doped carbon as an electrocatalyst for oxygen reduction reaction

Doped carbon materials have gained a lot of attention recently due to their wide array of applications. These doped carbon materials have a tremendous potential to replace expensive metal based electrocatalysts in fuel cells. A recently established microwave assisted technique, which does not make use of any inert or reducing gases, has been used to synthesize novel silicon (Si), phosphorous (P) co-doped carbon (SiPDC), as yet not reported in the literature. The method is simple, rapid and economical. Tannin, a renewable resource material is chosen as the carbon source, polyphosphoric acid is utilized as the dehydrating agent/P source and silicone oil is chosen as the Si source. Brunauer–Emmett–Teller analysis reveals the surface area of SiPDC to be 641.51 m2 g−1 and X-ray photoelectron spectroscopy confirms the doping of Si and P at 8.80% and 4.20% respectively. The doped carbon material is utilized for oxygen reduction reaction (ORR) in 0.1 M KOH. The mechanism of ORR is found to be a four electron reduction process based on rotating disk electrode studies. Electrochemical stability studies are performed to evaluate the effectiveness of the catalyst for practical applications.

A Comprehensive Review of Phosphorus Removal Technologies and Processes

Phosphorus removal from polluted water is a global concern considering the detrimental environmental effects that excess phosphorus has. Phosphorus can lead to poor water quality and aquatic life loss due to eutrophication when found in excess in aquatic systems. Industry and agriculture are two of the main sources that lead to the accumulation of phosphorus in wastewater. In an attempt to prevent harmful environmental effects of excess phosphorus, several techniques have been designed to remove phosphorus from wastewater. These techniques range from adsorption and precipitation to enhanced biological phosphorus removal and constructed wetlands. Adsorption and precipitation predominantly require the use of different metals in the phosphorus removal process. This article reviews the results found in the last nine years pertaining to phosphorus removal through the use of adsorption and precipitation using different metal-containing compounds. Advances concerning the parameters of enhanced biological phosphorus removal have also been studied and communicated in this article.

Photo-electrochemical hydrogen production using novel carbon based material

A transition to hydrogen as a major fuel could transform the US as well as global energy system increasing energy security while reducing environmental impact. This major transformation of our energy system would require a sustainable production of hydrogen using renewable resources. Hydrogen production using photo-electrochemical water splitting has been considered as a “holy grail” of sustainable hydrogen economy. Despite four decades of research since it was first shown that n-type TiO2 can be used for water splitting using sunlight, the search for a material that can efficiently harness solar energy for photo-electrolysis is still on. This paper will address some of the key challenges in the development of a material that is photoactive, stable, corrosion resistant and cost effective. This paper presents for the first time photo-electrochemical characterization of novel phosphorus, nitrogen doped carbon material (PNDC). The photocurrent density obtained was 0.416 mA/cm2, which is quite significant under visible radiation. This discovery opens up a large number of possibilities in development of a new class of carbon based materials for photo-electrochemical hydrogen production.

Photoelectrochemical Hydrogen Production Using Novel Heteroatom-Doped Carbon Under Solar Simulated Radiation

A transition to hydrogen as a major fuel could transform the United States and the global energy system, increasing energy security while reducing environmental impact. This major transformation of our energy system would require a sustainable production of hydrogen using renewable resources. Hydrogen production using photoelectrochemical (PEC) water splitting has been considered as a “holy grail” of sustainable hydrogen economy. PEC water splitting is achieved by direct utilization of solar energy using a semiconductor material as electrode. Despite four decades of research since it was first shown that n-type TiO2 can be used for water splitting using sunlight, the search for a material that can efficiently harness solar energy for photoelectrolysis is still on. This paper will address some of the key challenges in the development of a material that is photoactive, stable, corrosion resistant, and cost effective. For the first time, this paper presents the PEC characterization of a novel phosphorus-nitrogen-doped carbon material (PNDC). The photocurrent density obtained under visible radiation was 0.416 mA/cm2. This discovery opens up a large number of possibilities in development of a new class of carbon-based materials for PEC hydrogen production.