As Tauc equation is one of the most effective and common ways for the calculation of the band gap of semiconductors, you can certainly use it to get the band gap of MoS2. For more details, please refer to the enclosed paper.
Dear Sara, I am agree with other answers to your question that you can use Tauc model for determining the band gap of the your sample from experimental absorption spectrum result. because this model is a general one. then you can compare your obtained value with the known band gap energy value.