Challenges in depth:

Generating electricity on Mars is going to be challenging because of the lack of energy sources. The atmosphere on Mars is about 100 times thinner than Earth's atmosphere. The atmospheric pressure and the concentration of the atmosphere is low because the atmosphere is thin which will make the wind on Mar travel fast but will be extremely weak. This means the wind energy source can not be used to generate electricity. The greenhouse effect does not really happen in Mars because the heat is not trapped properly because the atmosphere is very thin which means most of the water is frozen. This means most of the water source can not be used to generate electricity. I have to figure out a way to generate electricity with technology that can use a feasible energy source on Mars or Earth for the initial settlement. The real challenges come after finding the energy source because I have to make sure my technology uses the available energy source and is able to operate properly in the environmental conditions of Mars. On Mars there are high levels of radiation because there is no ozone layer to block them out. This radiation in Mars can disrupt the monitoring systems of electricity generators. Or even worse they can create leakage currents between circuits. The high winds on Mars create dust Storms which happen very often. These dust storms can build up on technology and act as an insulator which can overheat technology or burst batteries. If enough dust accumulates through the dust storms, the rust particles can stop the flow of electricity because they are poor conductors. Mars is an extremely cold planet because the average temperature on Mars is about -60 degrees Celsius and the poles can be as cold as -125 degrees Celsius. Cold temperature can break technology because of thermal contraction. Cold temperature can cause a battery to lose its charge because the molecular action slows down due to the fluid getting thicker. Components of my technology must be made in Earth so that the colonists only have to assemble the technology because the initial colony will be small and can not protect people from the natural elements. I have to make modifications on my technology so that it is appropriately protected to work in the Martian environment. I have to make sure that my technology is effective and will be a reliable power source for the colony until new technologies are made to generate electricity in Mars by using the hidden energy sources to generate electricity effectively.

Challenges 

“An electrocatalyst is a catalyst that participates in electrochemical reactions. Catalyst materials modify and increase the rate of chemical reactions without being consumed in the process. Electrocatalysts are a specific form of catalysts that function at electrode surfaces or maybe the electrode  surface itself.”

The soil factor and issue on Mars is having a major impact on the food and sustainable ecosystem needed, soil provides the need of nutrients for all the plants to grow, but that can not be independently produced by the soil on Mars. The soils and fertilizers that would be used as a solution may be organic waste or manure, because they are beneficial to plants because of their nutrients. Although animal manure has high levels of Nitrogen and Phosphorus which is a concern, there are many strategies on lowering and removing that so it won't impact the water and air quality of the environment. Many approaches include modifying the livestock 's diet so that their manure has naturally reduced nitrogen and phosphorus levels, while another method is to keep animals relaxed and healthy, which has been shown to help improve the reduction of nitrogen and phosphorus. Another effective method is the use of water to concentrate and remove the levels of nitrogen and phosphorus, the use of additional water in the martian soil process significantly adjusts the manure regimens. Available plants that can be planted in this soil include garden cress, arugula, tomato, radish, spinach, chives, peas, potatoes and leeks. I believe that as the civilization and exploration of Mars develops, so will the variety plants and possibly even animals on Mars available to us. Earth experiments have confirmed that Earthworms can be put into this soil which is a significant factor that could very well help the plantation, these earthworms can endure and reproduce in space and presumably on the planet of mars.They will further help mix organic matter into the soil, improve soil quality and water within it.

There were several other plans to develop a sustainable greenhouse on Mars, many of which would need to be built underground due to the increased radiation levels on the surface. Since the greenhouses are going to be underground, the plants and structure will not be subjected to potential weather conditions such as extreme cold weather but will rather use the planet's land to their advantage, it is also an efficient way to use less of the land surface.The greenhouses will use light emitting diodes (LEDs) as an alternative to sunlight, light concentrators can also be used to collect natural sunlight for the plants allowing them to have a sufficient amount of light. The use of a recycling system for these Mars Greenhouses is a sustainable method for waste and water resources, the plants would conserve and reprocess the waste and water they have been using which is effective for another plants. These greenhouses will provide a controlled environment for these plants, I believe that they can fully support and withstand the conditions on Mars for a long-term period. And as plants start to grow in these underground mars greenhouses, they will start to develop and grow accustomed to the environment and to the conditions that will make them easier to grow. Due the fact that the soil on Mars is incompatible with the plants and has poor nutrient levels, another soil and fertilization that is discussed in my other solution will be utilized. 
The image below is an example of an underground greenhouse on Mars.