ADVERTISEMENT

Solar Photoactive Materials For Hydrogen Generation And Water Treatment

Solar photoactive material like TiO2 has a wide range of applications. It can be used in photovoltaic (PV) cells, hydrogen generation, water treatment, and much more.

The demand for renewable energy resources is increasing day by day due to its environment-friendly nature, never-ending source, and cost-effectiveness. Various renewable fuels are available in nature and can be used for energy generation. However, hydrogen fuel is the most efficient in terms of energy content and pollution effect. Hydrogen is produced by different methods viz. water splitting and biomass conversion. A TiO2 catalyst is activated in the presence of UV irradiation and generates hydrogen via photocatalytic water splitting [1]. Water splitting using solar PV cell is also very popular.

ADVERTISEMENT

Water is a priceless natural resource. Water is contaminated by various industrial effluents. This wastewater can be treated and recycled for further use. Water recycling reduces freshwater consumption as well as environmental pollution. The advanced oxidation process (using TiO2 and UV irradiation) is a very popular method for wastewater treatment. This UV/TiO2 process oxidizes the contaminants and produces less toxic final products [2].

For both the above-mentioned methods, TiO2 photocatalyst uses UV irradiation for its activity. This photocatalyst has a band gap of 3.2 eV. Therefore it will be activated in presence of UV light. We need to use artificial UV source since solar irradiation contains a very small fraction of UV. Utilization of visible light is necessary for the economic operation of these processes. Therefore, enormous research has been conducted to develop a visible light/solar-active TiO2 photocatalyst [3].

Photocatalytic activity of TiO2 depends on various factors such as structural, morphological, and optical properties. In a study by Singh and Dutta, a sol-gel process is used to synthesize TiO2. Proper controlling of the process parameters during the synthesis process enhanced the TiO2 quality since crystallinity and surface area play a vital role in the overall performance of the catalyst. Calcination temperature and pH are controlled to get optimum particle size and crystal size [3]. Figure 1. shows that the agglomeration rate is different at different temperatures. The synthesized TiO2 powder consists of fine particles and showed a lower rate of agglomeration that increases on further calcination at higher temperatures.

Fig. 1. FE-SEM images of prepared TiO2 nanoparticles (a) As-prepared (b) 450 Ā°C (c) 600 Ā°C (d) 900 Ā°C (e) commercial TiO2 powder in terms of agglomeration rate [3]. Republished with permission from Elsevier from:Ā https://doi.org/10.1016/j.apt.2017.11.005.
Synthesis of mixed/co-catalyst of TiO2 and doping of various metal and non-metal substances improve the optical and electronic properties of the TiO2 photocatalyst [4]. Co-catalyst and doping can change the band gap of the TiO2 catalyst. Proper selection of co-catalyst and doping species is required for this purpose.

ADVERTISEMENT

Characterization of the catalyst is important since it confirms the performance of the catalyst by determining the composition, crystal properties, band gap energy, particle size, surface area etc. Characterization is done using various methods such as XRD, FE-SEM, UV-vis spectroscopy, FTIR, Raman spectroscopy, and BET surface area [3].

Energy crisis and water pollution will be diminished by using materials like TiO2 and TiO2-based catalysts.

These findings are described in the article entitledĀ Synthesis and characterization of solar photoactive TiO2 nanoparticles with enhanced structural and optical properties, recently published in the journalĀ Advanced Powder Technology.Ā This work was conducted byĀ RohiniĀ Singh andĀ SumanĀ Dutta from theĀ Indian Institute of Technology (ISM), Dhanbad.

References

  1. Suman Dutta; A review on production, storage of hydrogen and its utilization as an energy resource; Journal of Industrial and Engineering Chemistry 20(4) 2014, 1148ā€“1156
  2. S. Dutta, S.A. Parsons, C. Bhattacharjee, P. Jarvis, S. Datta, S. Bandyopadhyay; Kinetic study of adsorption and photo-decolorization of Reactive Red 198 on TiO2 surface; Chemical Engineering Journal 155 (2009) 674ā€“679
  3. Rohini Singh, Suman Dutta; Synthesis and characterization of solar photoactive TiO2 nanoparticles with enhanced structural and optical properties; Advanced Powder Technology 29(2) 2018, 211-219
  4. Rohini Singh, Suman Dutta; A review on H2 production through photocatalytic reactions using TiO2/TiO2-assisted catalysts; Fuel 220(2018) 607-620

ADVERTISEMENT

Comments

READ THIS NEXT

25 Clever Riddles For Kids

Riddles for kids are great to keep your children constantly solving problems and thinking outside the box. The riddles below […]

Hydrological And Shallow Flow Modeling: Solutions Converge

Hydrological modeling is at the core of many environmental, agricultural, and engineering applications, research, and practices. Decision-making on managing our […]

Facile And Scalable Fabrication Of Polymer-Ceramic Composite Electrolyte With High Ceramic Loadings For Solid State Lithium Ion Batteries

Economic growth requires energy. To support future U.S. economic growth, pursue national energy independence and reduce greenhouse gas emissions, development […]

What Is A Carpet Beetle (Bug)?

TheĀ carpet beetleĀ is a colloquial name given to a number of species of beetle classified in the Desmistidae family. Found all […]

Female And Male Gamete Cells: Called Sex Cells

Gamete cells, also known as sex cells, are the cells responsible for sexual reproduction. A male gamete is called sperm […]

What Continent Is Russia In: Asia Or Europe

You may be wondering what continent Russia is officially in. Russia is considered to be both in Europe and Asia […]

The Growing Public Mistrust Of Experts In A Digital Age

I think the people in this country have had enough of experts… from organizations with acronyms saying that they know […]

Science Trends is a popular source of science news and education around the world. We cover everything from solar power cell technology to climate change to cancer research. We help hundreds of thousands of people every month learn about the world we live in and the latest scientific breakthroughs. Want to know more?