The Great Leap Forward had nothing to do with it.

The schism was created due to the conflicting interests of China and the USSR as two continental and political powers which was only expressed through political rhetoric since communist states were not supposed to have imperialist tendencies (since according to Marxist-Leninist doctrine imperialism was the highest stage of capitalism, while socialism which evolved into communism). In reality politics is the same no matter what political ideology or system prevails and in a game where only one can win two is already a crowd.

China under Mao imagined itself as a leading force of Maoist revolutions which were seen as the rightful continuation of revolutionary tradition started in Russia. Maoists saw Stalin and Khrushchev as people who stopped the revolution after gaining full control over the society and trying to emulate capitalist societies (hence "state" capitalism) and used that to bash the Soviet "reactionaries" and promote their own version of Marxist doctrine as the only true revolutionary ideology.

It is interesting that the potential for the split became evident before it is officially noted. Namely in 1956 when Stalinist regime collapsed in Poland - which was the most important Soviet bloc country due to geography - and communist politicians with a more "nationalistic" attitude were on the verge of taking over due to the spreading of the political sentiments from Hungary (which had its famous but failed uprising in 1956) Khrushchev considered military intervention to restore the previous government. The military units stationed in Poland even left the bases and were on their way towards Warsaw (capital) and expected to be confronted by Polish military which also was put on alert when Chinese delegation in the USSR demanded that the intervention be stopped.

It was at that moment that the USSR realized that it no longer was the only important player in town and the split became inevitable as a result of Chinese challenge to Soviet authority.

Short answer: Greap Leap Forward had many policies like Stalin's such as collectivization. At that time Khrushchev denounced Stalin and many of his policies. So that's one

Also,the schism wasn't just about Great Leap Forward. Khrushchev was seen by Mao as a revisionist for denounced what he believed as "socialism" and his idea of peaceful coexistence with the Western. Great Leap Forward was just one attempt to create what Mao believed to be "socialism" - such like Stalin's policies.