Ooh good idea. Here are a few potential topics
1. ADHD: lived experiences. Here you could maybe focus on combatting adhd stereotypes. Maybe even interview a few people diagnosed with adhd about their experience with it
2. Science of ADHD: here you could explain theories about adhd and the cause. You could go into why our medications work and why our brains don’t function like other peoples
3. ADHD in young adults: this seems to be your audience so it would attract attention. It could give insight into adhd affecting people who are older. This could be helpful because people often just think of little kids when they hear adhd