A Columbia PhD student has been killed by his boyfriend who shot him in the head after an argument.

Devon Wade, a promising 28-year-old student whose mentors said he would 'change the world', died after being shot at his home in Houston, Texas, on Sunday night.

His boyfriend Mario Jerrell Williams, 29, turned himself in to police shortly afterwards and admitted shooting him.

Williams is being held on $100,000 bond and is charged with first degree murder.

On Sunday night, he went to the home which Wade shared with twin brother but was asked to leave.

Devon Wade, 28, (left) died on Sunday after being shot in the head by 29-year-old Mario Jerrell Williams, 29, (right) who told police he was his boyfriend when he turned himself in for his killing

He says he returned a short time afterwards and began fighting with Wade, who he said punched him in the face and chased him downstairs.

Once downstairs, he shot him and then fled. When he turned himself in to police later, he said he was his boyfriend, Click 2 Houston reports.

Wade's twin brother, who was asleep upstairs, then found his brother lying on the ground bleeding.

He said he saw Williams fleeing the scene on security cameras installed around the home. It is not clear what the pair were arguing about or how long they had been together.

Wade was known locally for his community efforts and had already been praised for overcoming a difficult start in life to pursue academia.

The shooting happened at Wade's home in Houston, Texas, on Sunday night

Wade, 29, had already graduated from the Louisiana State University and had almost completed his PhD when he died. He was a well known member of the community who was passionate about charity and youth programs (seen right running a triathlon recently)

He was in the middle of a PhD in sociology at Columbia University in New York and had already graduated from Louisiana State University after being given a scholarship from a local law firm in Houston.

He had not long returned to Houston to complete his dissertation on the poverty and incarceration among the black community.

As news of his death spread on Tuesday, friends took to social media to eulogize him in disbelief.

'Great inspiration and a bright light now dimmed with sadness.

'To some he initially seemed destined for failure, however beat all odds and made outstanding accomplishments,' said one friend.

Devon's twin brother Stevon (right) was at the home on Sunday night when he died. He said he woke up to the sound if gunshots and then found his brother on the floor downstairs bleeding

'Statistically, Devon wasn’t expected to graduate high school. Devon’s parents were incarcerated [but] he overcame his unfortunate circumstances, graduated with Honors from LSU with a degree in Criminology, and was completing a PhD program at Columbia University.

'Devon dedicated his life to serving and encouraging others.

'He was committed to making society and the justice system better,' said another friend.

Devon and his brother were raised by his grandparents in Houston.

Columbia University said it will award him his doctorate posthumously.

