${\mathrm{WTe}}_2$ and ${\mathrm{MoTe}}_2$ monolayers offer a rich platform for exploring topological quantum phenomena, including electrically switchable circular photogalvanic effects, rectification, and nonlinear Hall effects (NLHE). In time-reversal symmetric systems, a nonzero Berry curvature dipole (BCD) is essential for realizing NLHE, and such a BCD-induced NLHE has been observed in pristine ${\mathrm{WTe}}_2$ and ${\mathrm{MoTe}}_2$ monolayers. However, the intrinsic BCD in these materials is quite small—on the order of 0.01 Å—posing significant challenges for experimental detection and practical implementation of nonlinear Hall phenomena for technological applications. In this work, we theoretically design a monolayer ${\mathrm{T}}_d\text{−}{\mathrm{W}}_{0.5}{\mathrm{Mo}}_{0.5}{\mathrm{Te}}_2$ (i.e., ${\mathrm{WMoTe}}_4$) by chemically substituting elements in the parent ${\mathrm{WTe}}_2$ and ${\mathrm{MoTe}}_2$ monolayers. Our first-principles calculations confirm the dynamical, elastic, and mechanical stability of the designed monolayer. Remarkably, the ${\mathrm{T}}_d\text{−}{\mathrm{W}}_{0.5}{\mathrm{Mo}}_{0.5}{\mathrm{Te}}_2$ monolayer exhibits a significantly enhanced intrinsic BCD of $\sim$ 4.5 Å (without any strain or external tuning) near the Fermi energy, which is nearly 100× larger than that in pristine {W, Mo}${\mathrm{Te}}_2$ monolayer. This enhancement is attributed to a reduced energy gap, which amplifies Berry curvature contributions near the Fermi energy. Given that bulk ${\mathrm{T}}_d\text{−}{\mathrm{W}}_{0.5}{\mathrm{Mo}}_{0.5}{\mathrm{Te}}_2$ has already been synthesized, the proposed monolayer offers a readily accessible and strain-free 2D platform to harness substantial NLHE for next-generation quantum devices, including high-performance rectifiers and sensors.

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• Electronic structure
• First-principles calculations
• Hall effect
• Spin-orbit coupling
• Topological materials