Present in the Taittiriya Aranyaka of the Krishna Yajurveda, the Sadyojata mantra is dedicated to the Sadyojata form of Lord Shiva.
This Mantra is part of the popular Panchabrahma mantras of Lord Shiva, which praise the five forms of Lord Shiva: Sadyojata, Vamadeva, Aghora, Tatpurusha, and Ishana.
Coming to the Sadyojata Mantra, it expresses total surrender to Lord Shiva’s form, seeking liberation from rebirth by attaining Moksha.
Lord Sadyojata is the western face of Lord Shiva, representing the Srusti Shakti or the power of creation.
Chanting this Mantra has immense benefits, and practising it regularly through Japa blesses the devotee with creative aspects, perfection, growth, Radiance, prosperity, wisdom, splendour, life, and divine powers.

Sadyojata Mantra in Sanskrit, IAST English with Meaning
सद्योजातं प्रपद्यामि
सद्योजाताय वै नमः
भवे भवेनाति भवे भवस्व माम्
भवोद्भवाय नमः॥
Sadyojātaṁ Prapadyāmi
Sadyojātāya Vai Namaḥ
Bhavé Bhavénāti Bhavé Bhavasva Mām
Bhavodbhavāya Namaḥ॥
Meaning: I surrender to Lord Sadyojata (The form that represents the creative aspects and rapid manifestation of Lord Shiva), and my salutations to that Lord Sadyojata.
O Lord Bhava (Shiva), please protect me from the cycle of birth and rebirth. Salutations to the one from whom all the creation had emerged.
Note: The Vedic version (Kṛṣṇa Yajurveda, Taittirīya Āraṇyaka), as well as several ancient texts, does not include Namo in the second line of the Mantra (like sadyojataya vai namo namaha). Therefore, the word Namo is omitted.