WorksheetsEnergy harvesters
Total questions: 19
Worksheet time: 10mins
A Self-Charging Supercapacitor System (SCS) integrates which two major components?
Battery and solar cell
Energy harvester and supercapacitor
Fuel cell and electrolyte
Generator and transformer
Which of the following is not an energy harvester used in SCSs?
Piezoelectric Nanogenerator
Triboelectric Nanogenerator
Photovoltaic cell
Lead-acid battery
PENG in SCS stands for:
Photoelectric Nanogenerator
Piezoelectric Nanogenerator
Potential Energy Nano Grid
Photonic Electrochemical Nano Gate
In a triboelectric nanogenerator (TENG), energy is generated mainly through:
Heat transfer
Contact and separation of materials
Electrolysis
Magnetic induction
In an SCS, charges are stored in the supercapacitor via:
Slow chemical reactions
Electric double-layer formation and redox reactions
Combustion reactions
Thermal excitation
Which material is commonly used in piezoelectric nanogenerators for SCSs?
Graphite
ZnO nanowires
Copper sulfate
Sodium chloride
In photo-supercapacitors, which form of energy is harvested?
Mechanical
Thermal
Solar (light)
Chemical
The main role of the separator in an SCS is to:
Generate charges
Prevent electrode contact while allowing ion flow
Convert heat into electricity
Store electrons
Which of the following is not a typical electrode material in SCS supercapacitors?
Graphene
MnO₂
Conducting polymers
Quartz crystal
The electrolyte in an SCS primarily helps in:
Blocking ion movement
Enabling ion transport
Generating light
Cooling the electrodes
SCSs are especially suitable for which type of devices?
Gas turbines
Wearable electronics
Large industrial motors
Thermal power plants
The voltage generated by an energy harvester in an SCS is:
Stored directly in the supercapacitor
Converted into heat
Lost due to resistance
Always rectified into AC power
Which of the following is an advantage of SCSs?
Require constant external charging
Work only at high temperatures
Can charge themselves from ambient energy
Cannot be integrated with sensors
In an SCS, the current collector is used to:
Absorb sunlight
Transfer electrons to external circuits
Produce ions
Generate mechanical pressure
An example of SCS application in robotics is:
Vibration dampers
Artificial e-skin that powers itself
Structural beams
Conveyor belts
In CVD synthesis of GQDs, which metal is commonly used as a substrate?
B) Copper or Nickel
A) Iron
C) Lead
D) Silver
What is the purpose of annealing the metal substrate in hydrogen before CVD?
B) To remove surface impurities
A) To deposit carbon atoms
C) To increase photoluminescence
D) To oxidize the substrate
A major advantage of GQDs over heavy-metal-based quantum dots is:
B)
D)
Poor conductivity
High toxicity
Eco-friendliness and low toxicity
High melting point
GQD formation in CVD occurs when:
Cooling is done very slowly
Growth time and precursor flow rate are tightly controlled
Growth temperature is low
An oxidizing atmosphere is used
