  Two-dimensional materials with unique physicochemical properties promote
photocatalytic activities. As the 2D material composites research studies the
statistical average of complex catalytic behaviors, an integrated photonic
platform allows clean and single flake level photo-catalytic investigations
with precisely quantified photocatalytic activities. In this paper, we track
fluence-dependent photo-oxidation in two-dimensional Tellurene (2D Te) by the
evanescently coupled micro-resonator. Nearly 32 perent of oxidation is achieved
in 10 nm 2D Te flake, compared to only 4.5% oxidation in 30 nm sample, probed
by the resonance shift in silicon microring resonators (MRRs) substrate. The
wider bandgap in the few layers of 2D Te allows faster charge transfer to
adsorbed oxygen for a more efficient photocatalytic redox reaction. The
photo-oxidation in hybrid 2D Te results in an invariant lineshapes of optical
transmission resonance for wavelength trimming (more than 3 times resonance
bandwidth). The low threshold power, near-infrared, and in-waveguide resonance
trimming scheme is compatible with most integrated photonic setups for easy
fixing the nanofabrication-induced random resonance deviation for integrated
photonic circuit applications in wavelength-division-multiplexing systems and
spin qubits quantum computing.
