RMSE, MAE, MSE, and R² values from CatBoost, GBR, and XGBoost models for the work function prediction of AB-type 2D nanomaterials on the training and the test sets after parameter optimization.

Model	RMSE (eV)		MAE (eV)		MSE (eV)		R 2
	Train	Test	Train	Test	Train	Test	Train	Test
CatBoost	0.03	0.28	0.02	0.20	0.00	0.08	0.99	0.92
GBR	0.02	0.31	0.05	0.22	0.00	0.09	0.99	0.90
XGBoost	0.09	0.30	0.04	0.21	0.00	0.09	0.98	0.90