This article focuses on thwarting reverse-engineering attacks and intellectual property (IP) theft by leveraging charge-recycling adiabatic circuits. The adiabatic circuit operation has recently received attention for the Internet-of-Things (IoT) applications due to high energy efficiency and enhanced security characteristics. Such applications typically consist of resource-constrained designs and are often deployed in the field, making them particularly vulnerable to malicious attacks. PhaseCamouflage is a circuit obfuscation technique that leverages the inherent phase differences (PDs) in power supply voltage of adiabatic logic gates and exhibits strong resistance against structural/removal attacks. The proposed method relies on inserting camouflaged PDs in the power supply voltage of subsequent logic gates while still producing a functional netlist. PhaseCamouflage is a unique logic obfuscation technique with low overhead, particularly applicable to pervasive computing applications where both efficiency and security are of primary concern.