A series of [Cu(N-N)(PPh3)2]BF4 complexes were synthesized and characterized in this paper, where N-N and PPh3 suggest a diamine ligand and triphenylphosphane, respectively. Their structures were revealed by single crystal analysis and density functional theory calculation. The photophysical feature comparison between those Cu(I) complexes revealed the correlation between emission performance and diamine ligand structure. In addition, it was found that the emissive states were vulnerable to O2 attack, making them potential oxygen sensing probes. They were thus doped into a silica molecular sieve SBA-15 to systematically explore their oxygen sensing performance. High sensitivity and good photostability were observed from the composite sensing systems.