Quantum Computers face a critical limitation in qubit numbers, hindering their progression towards large-scale and fault-tolerant quantum computing.A significant challenge impeding scaling is crosstalk, characterized by unwanted interactions among neighboring components on quantum chips, including qubits, resonators, and substrates.We motivate a general approach to systematically resolving multifaceted crosstalks in a limited substrate area.We propose QPlacer, a frequency-aware electrostatic-based placement framework tailored for superconducting quantum computers, to alleviate crosstalk by isolating these components in spatial and frequency domains alongside compact substrate design.QPlacer commences with a frequency assigner that ensures frequency domain isolation for qubits and resonators.It then incorporates a padding strategy and resonator partitioning for layout flexibility.Central to our approach is the conceptualization of quantum components as charged particles, enabling strategic spatial isolation through a 'frequency repulsive force' concept.Our results demonstrate that QPlacer carefully crafts the physical component layout in mitigating various crosstalk impacts while maintaining a compact substrate size.On various device topologies and NISQ benchmarks, QPlacer improves fidelity by an average of 37.5× and reduces spatial violations (susceptible to crosstalk) by an average of 12.76×, compared to classical placement engines.Regarding area