Researchers synthesize highly crystalline pyrite at low temperatures useful for fabricating high energy density supercapacitors (GS Paper 3, Science and Technology)
Why in news?
- Researchers have synthesised highly crystalline pyrite FeS2at low temperatures and utilized them for fabricating electrochemical energy storage devices such as batteries and high energy density supercapacitors (SCs).
Transition metal sulfides (TMS):
- Transition metal sulfides (TMS) are an important class of inorganic materials and find applications in diverse fields including electrochemical energy storage devices such as batteries and supercapacitors (SCs).
- Solid-state synthetic methods are used to generate metal sulfides from the corresponding metal salts or their equivalent oxides usually by annealing at high temperatures.
Details:
- The Centre for Nano and Soft Matter Sciences, Bengaluru demonstrated the low-temperature synthesis of crystalline pyrite FeS2 through a solid-state synthesis route. They have utilized a metastable oxyhydroxide (FeOOH) precursor for this process.
- They reported stabilising this intermediate oxyhydroxide and utilizing it as a precursor for sulfidation, in the presence of H2S gas.
- Using a metastable precursor helped in lowering the annealing temperature, as FeOOH converted into pyrite FeS2 with fairly good crystallinity at a low temperature.
- This synthetic route of obtaining sulfides from their corresponding metastable oxyhydroxides can be extended to other transition metals to obtain crystalline materials in an energy intensive way.
Significance:
- Electrodes for high-energy density SCs were fabricated from the as-synthesized FeS2, resulting in superior performance in the presence of organic and ionic-liquid (IL)-based electrolytes.
- This could be attributed to the improved conductivity as a result of good crystallinity of the material as well as the significantly enhanced wettability of the FeS2 electrode in the presence of the organic and IL-based electrolytes.
Way Forward:
- The FeS2 electrode exhibited high energy and power densities, clearly highlighting the role of the synthetic procedure employed for enhancing electrochemical properties.
GLOF triggered Sikkim disaster day after Nepal quake
(GS Paper 3, Environment)
Why in news?
- Many people lost their lives in the aftermath of a cloudburst above Lhonak Lake in North Sikkim, which has subsequently induced a flash flood within the Teesta river basin.
- The flash floods are being said to be the result of the Glacial Lake Outburst in the South Lhonak Lake where water over an area of 105 hectares drained out, creating a flash flood downstream.
What is a Glacial Lake Outburst Flood?
- Glacial Lake Outburst Floods (GLOFs) are natural disasters that can be catastrophic, triggered by the sudden release of water from glacial lakes. Understanding the causes, mechanisms, and factors leading to GLOFs is crucial for safeguarding vulnerable regions and populations.
- These are flash floods of extreme magnitude that occur when the natural dams, made up of ice, rock debris, or moraine, hold back glacial lakes rupture or are breached. These glacial lakes typically form as a result of the melting of glaciers in high-altitude areas.
- The water accumulates in depressions, often trapped by glacial debris or ice dams, creating a potentially dangerous situation.
Factors responsible:
- Several factors contribute to the occurrence of GLOFs, the primary factor being the accelerated melting of glaciers due to rising global temperatures. As glaciers shrink, they feed water into the glacial lakes, increasing their volume.
- Ice Dam Failure is another factor as when the volume of water in these lakes surpasses the capacity of the natural dam (often composed of ice or moraine), the dam can weaken or break, unleashing a torrent of water downstream.
- Another factor remains a major trigger event that could lead to this condition. Various triggers, such as earthquakes, avalanches, or landslides, can induce ice dam failure. These events shake loose the ice or debris, weakening the dam and causing it to give way. There are speculations that the outburst could have been triggered by the Nepal Earthquake a day before, which was a magnitude 6.2.
- Once a GLOF is initiated, the release of water can be sudden and catastrophic. The immense volume of water flows rapidly down valleys, gaining destructive force as it descends.
- What makes the floods extremely dangerous is not just the speed factor, the surging floodwaters carry with them rocks, debris, and sediment, creating a destructive force capable of obliterating infrastructure, villages, and agricultural land downstream.
Increased occurrence:
Several factors have contributed to the increased occurrence of GLOFs in recent years:
- Climate Change: The warming of the Earth's climate accelerates glacier melting, leading to the growth and instability of glacial lakes.
- Glacier Retreat: As glaciers shrink and recede, they expose more rock and debris, which can accumulate in the downstream areas, forming unstable natural dams.
- High-Risk Zones: Human settlements and infrastructure in proximity to glacial lakes are particularly vulnerable to GLOFs. Rapid urbanization and development in these regions exacerbate the risks.
- Monitoring and Early Warning: Inadequate monitoring and early warning systems in many affected areas limit the ability to predict and respond to potential GLOFs.
Aspirational Blocks Programme, Govt to spend Rs 100-cr in 500 most backward blocks
(GS Paper 2, Governance)
Why in news?
- The Union government will be spending Rs 100 crore this fiscal to improve governance and enhance the quality of life of people living in 500 of the most backward and poorest blocks of the country, as part of the ambitious Aspirational Blocks Programme (ABP).
Implementation:
- The NITI Aayog is implementing the ABP in 329 districts of the country.
- A three-year timeframe has been set for improving socio-economic indicators in five major areas; health and nutrition, education, agriculture, drinking water and sanitation, financial inclusion, basic infrastructure and overall social development.
Blockwise development:
- Of the 500 blocks, the maximum, 68, are in Uttar Pradesh, followed by 61 in Bihar, 42 in Madhya Pradesh, 34 in Jharkhand and 29 in Odisha.
- The ABP will support blocks to develop their development strategy, which will factor in block-specific challenges and opportunities.
- Blocks would identify key interventions across all the sectors of the ABP that could help achieve saturation of services and surpass the state average on key socio-economic parameters.
- All the blocks will be ranked every quarter, based on their performance. The financial incentives to blocks will also be given on a quarterly basis.
- A total of nine core sectors have been identified and relevant 11 central ministries and departments would see to it that blocks achieve the desired results in partnership with the respective state governments.
- Special focus would be given to 60 blocks in Odisha, Chhattisgarh and Madhya Pradesh, which are inhabited by vulnerable tribal groups.
Background:
- The ABP programme, launched by Prime Minister in January, takes off from the Aspirational Districts Programme that was launched in 2018 to improve living standards in 117 of the most under-developed districts across India.
- With the Aspirational Districts Programme completing five years, the Centre identified 500 of the poorest blocks to launch the ABP.
- A block is a subdivision of a district. In all, there are 7,000 blocks in the country. One-third of the blocks under the ABP fall in districts covered under the Aspirational Districts Programmes while 217 blocks have been identified in new districts.
