Global warming is an alarming issue in our daily life. As we know that CFCs and HCFCs have a great impact on ozone depletion and global warming process. So, there must be a cheaper way to detect CFCs and HCFCs from refrigerant products like refrigerator, aerosols, air-conditioner, etc. So, for the very first time, this paper proposes a novel highly sensitive dual-core bi-layer gold-coated surface plasmon resonance (DB-SPR)-based photonic crystal fiber (PCF) for sensing CFCs and HCFCs in the field of chemical and biosensing. The analysis is assumed at 20∘$\circ$C (293 K) for the concentration level of CFCs and HCFCs ranging between 20% and 80%. The entire numerical evaluation process is done by using finite element method (FEM) with a full vectorial software named COMSOL V-5.1 by examining the number of mesh elements of 228,120 which has better flexibility in the fabrication process. The proposed model can prove itself better than any other models by the justification of the major optical parameters, such as birefringence (Bi$i$), coupling length (Lc$c$), confinement loss (αc$\alpha c$), transmittance (Tx$x$), transmittance variance (Tv$v$), power fraction (Pf$f$), amplitude sensitivity (SA$A$), wavelength sensitivity (Sw$w$), figure of merit (FOM), resolution (Rl$$), resonance (R2), etc. which respectively corresponds to their maximum performance profiles of 0.038, 40 μ$\mu$m, 1140 dB/cm, −180 dB, 410 dB/RIU, 51%, −3200 RIU−1$-1$, 30450.43 nm/RIU, 1300, 1.25$$×$$10−5$-5$, 0.98712. So, it is evident that proposed SPR PCF can be a tough competitor in the field of biosensing and chemical sensing as well as gas sensing.