Welcome to the community, I suggest you read the following threads below regarding the PoW vs PoS arguments it's pros and cons:

• POW vs. POS
• PoW vs PoS- Proof-of-Stake Might be the Winner here (Save the Environment)
• PoW vs PoS (Decentralized)
• PoW and PoS; Pros and Cons
• PoW and PoS; Pros and Cons